Medications & Drugs

Key Messages

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These are the main health messages that should be conveyed to all future and new parents. They have been written in second person and at a reading level appropriate for the general public so that they can be shared with them directly. They are based on a consensus founded in scientific research and professional practice. Clicking an underlined word or group of words in the text will redirect you to the section in Supporting Evidence that deals with that topic.

In these key messages, medications include prescription, over-the-counter, and herbal products. Drug use includes recreational or street drugs such as marijuana, cocaine, and others. For information about tobacco and alcohol, see the Smoking and Alcohol files.

Talk to your health care provider about medications you are taking, are about to take, or considering stopping during your pregnancy or while breastfeeding.

Medications may reach your baby through the placenta or through your breastmilk. The potential harmful effects of medication on pregnant women or babies are not always known or studied.

It is important to discuss any medicines you are taking with your health care provider while you are planning your pregnancy or as soon as possible. Methadone treatment while pregnant or breastfeeding is safe for your baby.

Ask your health care provider the following questions about medication use during pregnancy.

  • Is this medication safe to take during pregnancy?
  • What are the benefits?
  • What are the risks?
  • Are there any alternatives?

If you need to take medication while breastfeeding, ask your health care provider if it is okay to breastfeed while taking this medication or if there are safer alternatives. Most medications are safe to take while breastfeeding.

Taking recreational or street drugs during your pregnancy or while breastfeeding is harmful to you and your baby.

Discuss any recreational or street drug use  with your health care provider before you are pregnant or as soon as possible. It is safest not to use drugs during pregnancy or while breastfeeding. If you are considering quitting drug use while pregnant speak to your health care provider about the safest way to quit.

Babies born to mothers who take drugs may:

  • Be born too soon and be smaller than average.
  • Have health problems.
  • Go through drug withdrawal if their mother uses drugs prior to birth.
  • Have problems learning.

Ask for help if you want to quit using recreational or street drugs.

It is never too late to reduce or stop using drugs. It can be very difficult to admit to drug use. Finding support from someone you can trust is key to getting help. Your partner, family members, or friends may be a great source of support. Speak with your health care provider about services to help you quit safely. Some people use drugs because of events in their lives such as abuse or trauma. Counselling or other services may help.

For help to stop using drugs:

  • Call ConnexOntario at 1-866-531-2600 for free, confidential information about alcohol and drug addiction services in Ontario.
  • Call the Centre for Addiction and Mental health (CAMH) at 1-800-463-6273 for a self-referral for assessment and treatment around addiction/substance use.

Learn more about medications and drugs.

You can find out more about medication and drug use during pregnancy and breastfeeding from the following resources. More suggestions can be found in the Resources and Links section.

  • Your health care provider
  • Telehealth Ontario 1-866-797-0000
  • Your local pharmacist

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Supporting Evidence

The supporting evidence is written in third person and is aimed at prenatal education providers. It is not intended to be shared directly with new and expectant families; it is meant to provide the background information and evidence for the key messages.

About Medications and Drugs during Pregnancy

Defining medications and drugs during pregnancy

The supporting evidence that follows will address medications including, prescription, over-the-counter, and herbal products as well as recreational or street drugs.

Prescription medications are drugs that can only be legally obtained with a medical prescription from a qualified health care provider. Products needing a prescription are regulated as drugs under the federal Food and Drug Regulations.1 In contrast, over-the-counter medications can be obtained without a prescription. According to the World Health Organization (WHO), herbal medicines include herbs, herbal materials, herbal preparations, and finished herbal products that contain active ingredients from plants.2 Not all herbal products sold are regulated, and quality and ingredients cannot always be assured.

Recreational or street drugs are substances taken for nonmedical purposes (usually for mind-altering effects). Such drugs include various amphetamines, anesthetics, barbiturates, opioids, and psychoactive drugs.3

The following drugs are discussed in greater detail because of their prevalence in the population and because of the specific consequences during the perinatal period.3

  • Cannabis
  • Cocaine
  • Amphetamines and methamphetamine.
  • Opioids such as heroin and methadone.

For information about the effects of tobacco and alcohol during the perinatal period, see the Smoking and Alcohol files.

National and provincial statistics

It is difficult to know how many pregnant women and breastfeeding mothers are on prescription medication and/or take over-the-counter medications. The National Longitudinal Survey of Children and Youth (NLSCY) reported that “between 1984 and 2003, up to 33 percent of Canadian women took medications during their pregnancies.” 4 According to Statistics Canada, women reported higher rates than men of prescription drug use.5 The reported rate of prescription drug use during pregnancy may be low due to individuals borrowing or sharing medications.

An Ipsos Reid survey done in 2010 shows that 73 percent of Canadians regularly take natural health products (NHPs) like vitamins and minerals, herbal products, and homeopathic medicines.1 There is no prevalence data on the use of herbal remedies during pregnancy.

Since recreational or street drug use is illegal, it is difficult to get accurate information about the prevalence of maternal drug use during pregnancy. Pregnant women may under-report drug use.6

According to the 2006 – 2007 Canadian Maternity Experiences Survey (MES), 7 percent of women reported using at least one recreational or street drug in the three months prior to pregnancy and 1 percent reported using street drugs during pregnancy.7 Women between the ages of 15 and 24 were most likely to report drug use during pregnancy, and 10.5 percent of women in Ontario reported drug use prior to pregnancy.7 Finally, according to the available information, the recreational or street drug most frequently used by pregnant women and women of childbearing age was cannabis followed by cocaine and opiates.8, 9

Who is at Risk?

Risk factors for use of prescription and over-the-counter medication

Women with chronic health conditions

The 2011 – 2012 Better Outcomes Registry & Network (BORN) report indicated that 28 percent of Ontario women giving birth in Ontario had health conditions that may or may not have required prescription medication. 10 With approximately 50 percent of pregnancies being unplanned, many women may take prescription and over-the-counter medications without knowing that they are pregnant. 7, 11 Women with chronic health conditions including, arthritis, asthma, hypertension, diabetes, depression, heart disease, or epilepsy that become pregnant are likely to be on medications. Pregnant women over the age of 35 are more likely to have pre-existing medical conditions, such as hypertension, arthritis, diabetes, and breast cancer. 12 As a result of pre-existing medical conditions, women of advanced maternal age are more likely to be taking medications. 13 Common examples are blood pressure medications and medications to control the symptoms of arthritis. Women with chronic health conditions may also be using over-the-counter medications or herbal remedies for managing chronic medical conditions.

Women with pregnancy-related conditions

Women with chronic health conditions may find that the symptoms of their illness change with pregnancy. With the physical and psychosocial changes that happen with pregnancy, many symptoms get worse. Pregnancy may also create new issues for all women such as nausea, vomiting, and sleep issues. 14 These conditions may increase a woman’s likelihood of accessing prescription, over-the-counter, and herbal products.

Adolescent mothers

Adolescent women are less likely to plan their pregnancy and may take longer to confirm or acknowledge their pregnancy and seek out medical care. These factors put them at higher risk of taking prescription and over-the-counter medication without consulting a health care provider to review risks, benefits, and alternatives. 15

Risk factors for recreational or street drug use

Some women are more likely to use recreational or street drugs during pregnancy than others.

The following factors have been found to be associated with drug use during pregnancy.16, 17

  • Low education level or family income level.
  • Historical trauma.
  • History of domestic violence.
  • Personal history or presence of mental health concerns (e.g., depression, anxiety disorders, and personality disorders).
  • Family history of substance use disorders.
  • Partner who drinks or uses drugs.
  • Personal history of drug use disorders.
  • Alcohol and tobacco use during pregnancy.

Prescription Medication

Categories of prescription medication

Physicians frequently rely on the Federal Food and Drug (FDA) pregnancy risk category system and the Compendium of Pharmaceuticals and Specialties (CPS) to evaluate the safety of medications during pregnancy. However, both the FDA classification system and the product monographs of the CPS are inadequate to address the complexity of weighing the benefits of treatment against the possible risk of drug exposure. 18

The FDA announced in May 2008 that they will replace the A, B, C, D, and X pregnancy risk classification system with a narrative framework consisting of several sections. 18 The new labeling information for medication during pregnancy will contain a risk summary section that incorporates human and animal data and a clinical consideration section that addresses risk assessment and how to handle inadvertent fetal drug exposure. 18

LactMed ®, a database managed by the Toxicology and Environmental Health Information Program (TEHIP) in the Specialized Information Services (SIS) division of the National Library of Medicine (NLM) within the National Institute of Health (NIH), contains information on drugs, herbal products, and other chemicals to which breastfeeding mothers may be exposed. It includes relevant scientific literature on the levels of these substances in breastmilk and infant blood if available and the possible adverse effects on the nursing infant. Suggested therapeutic alternatives are also provided where appropriate. A peer review panel reviews the data to assure scientific validity. LactMed ® has been suggested as the most reliable resource for safety recommendations in lactation. 19

An additional resource that may be used is Medications and Mother’s Milk. In this resource, Dr. Thomas Hale has created lactation risk categories for medications taken while breastfeeding that rates drugs from safest (L1) to contraindicated (L5). 20

Prescription medication during pregnancy

Medication should be prescribed during pregnancy when the expected benefits to the mother outweigh any potential risks. 21 The decision to take a prescription medication during pregnancy should be an informed decision made by a woman in consultation with her health care provider. In some cases, alternative treatments such dietary and lifestyle changes may be adequate in managing some chronic health care issues during pregnancy and/or may result in requiring a lower dose of medication to achieve stabilization. Prescription medication during pregnancy should be taken at the lowest therapeutic dose for the shortest period needed. 21

Many physiological changes that occur during pregnancy may modify the pharmacokinetics of drugs, and a woman’s dosage may need to be modified to ensure therapeutic levels. 22, 23 It is important for pregnant women to maintain the appropriate dose of the required medication to maintain control of chronic illnesses such as depression, diabetes, and hypertension as all have potentially adverse effects on both the mother and the baby. 22, 23

Pregnant women who need to be on prescription medication may worry and have feelings of guilt. However, research has shown that most women and health care providers overestimate the teratogenic risk associated with drug use during pregnancy. 22

Every pregnancy has the risk for major malformations regardless of fetal drug exposure. 24 When considering the risks of all teratogens, including drug exposure, four areas of fetal development are considered: growth alteration; functional deficit; structural malformation; and death. 23,24 The effects of a medication on the unborn baby depend on the amount of the drug taken; the frequency of use; the stage of fetal development; and genetic susceptibility. 23, 24, 25 Adequate nutrition may also play a role; for example, adequate folic acid intake may decrease the risk of certain malformations in women with epilepsy. 26, 27

The most significant adverse effects of medications often occur early in pregnancy before many women realize that they are pregnant. 23 The baby’s organs are forming during week’s three to eight and during this time the fetus is at risk of developing major anomalies. Toward the end of pregnancy, exposures may increase the risk for more subtle abnormalities as well as fetal withdrawal symptoms for some drugs. 24

See Appendix A for a listing of common maternal medical conditions, effects on pregnancy/infant, and safety considerations for prescription medication in pregnancy.

Prescription medication and breastfeeding

The benefits of breastfeeding to both child and mother are very clear. Some mothers will require medication of some type during the time they are breastfeeding. While it is true that most medications enter breastmilk to some degree, with a few exceptions, the concentrations of most medications in breastmilk are very low, and the dose the baby receives is often sub-clinical. 28 Package inserts and information provided in the CPS most often indicate contraindications to breastfeeding. This information is mainly due to concern about liability and does not accurately represent the amount of medication present in breastmilk. 28 LactMed® and Hale’s lactation risk categories can be used as reliable resources when counselling breastfeeding women about prescription medication and breastfeeding.

Domperidone has been prescribed (by some physicians) to increase milk supply; this is an off-label application of the drug. This medication has not received approval from Health Canada to be used to support lactation. 29 In March 2012, Health Canada released an advisory to health care professionals and the public warning of possible, serious side effects associated with the use of domperidone. 29 The warning was based on two studies reporting an association of domperidone with serious abnormal heart rhythms and sudden cardiac death (SCD). 30,31 According to Motherisk, the results of the studies are not directly applicable to breastfeeding and should not change the way a health care provider would normally manage otherwise healthy, breastfeeding women. 29 Domperidone should be used at the lowest effective dose for the shortest time possible. 29

It is not recommended to use narcotic analgesics (e.g., codeine) for more than four days especially when breastfeeding a newborn infant. Newborn infants appear to be particularly sensitive to the effects of even small dosages of narcotic analgesics. Maternal use of oral narcotics during breastfeeding can cause drowsiness, central nervous system depression, and even death in the breastfed infant with a possible role for pharmacogenetics. 32

Over-the-counter medication for pregnant women

The purpose of over-the-counter (OTC) medications during pregnancy is to help women with symptoms they might experience during their pregnancy.

There is a general misconception that since OTC drugs are readily available and viewed as safe for adults they are acceptable during pregnancy. OTC medications should be treated the same as prescription medication. Therefore, if a woman is considering taking an OTC medication, the safety of taking the medication should be discussed first with her health care provider and/or pharmacist. 33, 34

Common over-the-counter medications

The following table provides an overview of physical complaints; over-the-counter medications; safety for mother and baby; and complimentary approaches for expectant mothers and their babies.

Table 1: Common over-the-counter medications

Physical complaints Over-the-counter medications Safety for mother and baby Complimentary approaches
Pain/fever/ headache analgesic / antipyretic:

  • acetaminophen (Tylenol®)
  • Pain reliever of choice during pregnancy for short-term pain relief when used at the recommended dose. 35·
  • There are many acetaminophen-containing products that also contain other medications; these should be assessed for safety before use.
  • Taking toxic doses of acetaminophen has been associated with liver toxicity in the fetus.36
All pregnant women should consult their health care provider regarding fever. If it is a fever related to a mild illness (e.g., a cold), a woman should:

  • Keep well-hydrated.
  • Rest.

Frequent, unusual headaches need to be assessed by a health care provider to rule out an underlying problem with high blood pressure. See the Physical Changes during Pregnancy file.

If a woman experiences a headache, the following may help:

  • Lie down in a cool, dark room and place a cool cloth on her head.
  • Ask a support person for a massage of her neck or back.
  • Practice good posture.
  • Eat small, frequent meals as her headache may be linked to low blood sugar.
Pain/fever/headache/backache nonsteroidal anti- inflammatory drug, NSAID:

  • aspirin, ASA (Bayer® ASPIRIN®)
  • Aspirin should be avoided during pregnancy unless specifically recommended by a doctor.
  • Low-dose aspirin (80 mg/day) has been recommended for certain medical conditions and has not been linked with any adverse neonatal outcomes. 37
  • Aspirin can interfere with blood clotting and can contribute to bleeding for both the mother and the baby, especially toward the end of pregnancy or during birth. 38
  • Used in high doses in the third trimester, aspirin can lead to the premature closure of a vessel (i.e., ductus arteriosus) in a baby’s heart that may lead to elevated lung pressure in the newborn (i.e., persistent pulmonary hypertension). 39
  • When taken late in pregnancy, aspirin might delay the onset of labour, reduce the strength and frequency of contractions, and increase the length of labour due to inhibition of prostaglandins. Aspirin can also increase the risk of hemorrhage at delivery and cause bleeding problems in the newborn. 39
See the above-noted complimentary approach for acetaminophen for ways to treat pain.For back pain, a woman can also seek relief from a massage therapist, physiotherapist, osteopath and/or chiropractor.
Pain/fever/headache/backache nonsteroidal anti- inflammatory drug, NSAID:

  • ibuprofen (eg. Advil®,

Motrin ®)

  • A few studies have suggested a small, increased risk of spontaneous abortion and birth defects such as gastroschisis, cardiac defects, and oral clefts with the use of NSAIDs in the first trimester. 40,41,37
  • Use of ibuprofen in the third trimester raises concerns about premature closure of a vessel (i.e., ductus arteriosus) in a baby’s heart that may lead to elevated lung pressure in the newborn (i.e., persistent pulmonary hypertension). 42,41
  • The use of ibuprofen toward the end of pregnancy may inhibit labour or cause a reduced amount of amniotic fluid (oligohydramnios). 41
  • It is recommended that women only use ibuprofen under a health care provider’s supervision during the third trimester. 41
See the above-noted complimentary approach for acetaminophen for ways to treat pain.For back pain, a woman can also seek relief from a massage therapist, physiotherapist, osteopath and or chiropractor.
Cough/cold antitussive:

  • dextromethor-phan hydrobromide (Benylin ®, Buckley’s ®)
  • Pregnant women are prone to colds and flu because their immune system is slightly lowered during pregnancy. 43
For cough/cold symptom relief, a woman can:

  • Rest at home.
  • Drink plenty of fluids.
  • Avoid smoking or being exposed to second-hand smoke.
  • Use non-medicated cough drops to relieve a sore throat.
Nasal congestion decongestant:·

  • oxymetazoline hydrochloride (Dristan®, Vicks ®)
  • phenylephrine hydrochloride (Sudafed PE®)

decongestant /antihistamine:

  • phenylephrine hydrochloride and bromphenira- mine (Dimetapp ®)
  • pseudoephed- rine and cetirizine hydrochloride (Reactine ®)
  • Many nasal sprays contain oxymetazoline. This compound clears the sinuses by tightening the small blood vessels of the nasal passages. It has the potential to tighten the arteries leading to the uterus. 37
  • Decongestants such as phenylephrine hydrochloride and pseudoephedrine are OTC medicines used to relieve nasal congestion caused by colds and hay fever. These can cause blood vessel narrowing and elevate blood pressure. It is best to avoid decongestants during pregnancy although the risk for birth defects is low. 45
To deal with nasal congestion a woman can:

  • Drink plenty of water daily to help keep nasal secretions thin.
  • Use saline (saltwater) nasal spray or drops.
  • Avoid cigarette smoke and other air pollutants (see the Smoking file for smoking cessation support)
  • Use a facial steamer or take a hot shower and let the steam open congested nasal passages.
  • Smear a dab of Vicks ® VapoRub ™ under the nose.
  • Use a vapourizer.
Diarrhea antacid/ antidiarrheal:

  • bismuth subsalicylate (Pepto-Bismol ®)
  • Use of bismuth subsalicylate may result in absorption of salicylate and an alternative should be considered during pregnancy. 46
To manage diarrheal symptoms, a woman can:

  • Avoid high-fat, fried foods, spicy foods, milk and dairy products, and high-fibre foods.
  • Rehydrate with an electrolyte-containing solution.

The underlying cause of diarrhea should be investigated.

Heartburn antacid:

  • aluminum hydroxide, magnesium hydroxide, and simethicone (Gelusil ®, Maalox®)
  • simethicone (Mylicon®)
  • magnesium hydroxide (Phillips’® Milk of Magnesia)
  • magnesium hydroxide and calcium carbonate (Rolaids ®)
  • calcium carbonate (Tums ®)


  • ranitidine (Zantac ®)

proton pump inhibitor:

  • omeprazole (Losec ®)
  • These antacids are all safe to take during pregnancy. 47
  • H2-antagonists and proton pump inhibitors reduce the production of stomach acid and are not associated with an increased risk for adverse pregnancy outcomes. 47
To manage heartburn, a woman can:

  • Elevate the head of the bed, so her head and shoulders are higher than her stomach. In this way, gravity will help prevent reflux.
  • Eat small, frequent meals (i.e., every two to three hours).
  • Avoid foods such as coffee, tea, chocolate, soft drinks, and mint. Also, avoid fatty foods and spices.
  • Avoid eating or drinking for at least three hours before bedtime.
  • Chew sugarless gum to increase saliva production, which can help neutralize stomach acid.
  • Avoid lying down after eating.
  • Avoid wearing tight clothing as this can put pressure on the abdomen. 48
Acne acne therapy:

  • benzoyl peroxide (Clearasil ® StayClear ®)
  • salicylic acid
  • alpha-hydroxy acid
  • sulfur topical
  • OTC treatments for acne have not been associated with an increased risk when used during pregnancy. 51 The amount of product that gets to the developing baby, if any, is unlikely to be high enough to cause birth defects. 49
  • Retinoids should be avoided during pregnancy. 50
To manage acne during pregnancy, a woman can:

  • Keep her skin well-cleansed.
  • Avoid using facial creams and makeup that may aggravate acne.
Allergies: sneezing, runny nose, watery eyes antihistamine:

  • diphenhydra- mine hydrochloride (Benadryl ®)
  • chlorphenira- mine maleate (Chlor- Trimeton ®, Chlor-Tripolon ®)
  • loratadine (Claritin ®)
  • At recommended doses, diphenhydramine hydrochloride use during pregnancy has not been reported to be associated with an increased risk of adverse pregnancy outcomes. 51
  • High levels of diphenhydramine hydrochloride could cause uterine contractions.
  • There are a few reports of withdrawal symptoms in infants whose mothers took diphenhydramine hydrochloride on a regular basis during pregnancy. 52
  • Adult doses of some elixirs with high ethanol concentrations such as Benadryl ® might produce blood levels similar to those achieved by drinking alcoholic beverages. Women should be cautioned on taking these due to the high amounts of alcohol. 44
  • Loratadine (Claritin®) is a non-sedating antihistamine used to relieve the symptoms of seasonal allergies. Most studies do not suggest an increased risk for malformations. 53
To manage allergy symptoms, a woman can:

  • Limit exposure to anything that triggers her allergy symptoms.
  • Use a saline nasal spray. Use the spray as directed.
  • Rinse her nasal cavity with a neti pot once or twice a day.
  • Exercise
  • Use nasal strips at night. Over-the-counter adhesive nasal strips can help keep nasal passages open while sleeping.
  • Elevate the head of her bed
Constipation/ hemorrhoids laxative – stool softener:

  • docusate sodium (Colace ®)

laxative – bulking agent:

  • psyllium fibre (Metamucil ®)
  • polycarbophil
  • methylcellulose

laxative – osmotic laxative:

  • polyethylene glycol 3350, PEG 3350 (RestoraLAX ® GoLYTELY ®)

anti- hemorrhoidal – skin protectant/ astringent:

  • glycerin/ witch hazel (Tucks ®)

anti- hemorrhoidal – topical anesthetic/ vasoconstrictor / skin protectant:

  • pramoxine/ phenylephrine/ glycerin /petrolatum (Preparation H ®)

anti-hemorrhoidal – topical steroid:

  • hydrocortisone 1%
  • When used in recommended doses, docusate sodium has not been reported to be associated with an increased risk of adverse pregnancy outcomes or any birth defects. 54
  • Fibre laxatives such as Metamucil ® are safe to use.
  • PEG products are safe and effective and considered first-line therapy for constipation during pregnancy. 37
  • These anti-hemorrhoidal medications are safe products to use for hemorrhoids.


Treatment of constipation or hemorrhoids.

  • Avoid straining during defecation and avoid prolonged times on the toilet. 55
  • Use sitz
  • Drink at least 2.3 liters (9.5 cups) of water per day.
  • Eat a high-fibre diet.
  • Milk of magnesia.
  • Mineral oil (this may decrease the absorption of fat-soluble vitamins with regular use).
  • Glycerin suppositories. 56
Vaginal yeast infection antifungal:

  • miconazole nitrate (Monistat ®)
  • clotrimazole (Canesten ®)
  • fluconazole (Diflucan ®)
  • Pregnant women are more likely to get yeast infections than non-pregnant women; this may be due to higher estrogen and sugar content in vaginal secretions that create a desirable environment for yeast. 57
  • If a pregnant woman suspects she has a yeast infection, she should consult her health care provider as her symptoms may be a result of a different pathogen and, therefore, may require different treatment.
  • OTC antifungals are not associated with increased risk for birth defects. 57
  • Oral, low-dose fluconazole should be considered as a second-line therapy/treatment, and its short term use has not been associated with increased risk for birth defects. 58
Treatment of yeast infections includes:

  • Wearing cotton underwear.
  • Taking showers instead of baths.
  • Using unscented soaps.
Insomnia antihistamine:

  • diphenhydramine hydrochloride (Unisom ® Nytol ®, Sominex ®)
  • The use of diphenhydramine has not been associated with an increased risk for adverse pregnancy outcomes when used at recommended dose for short periods. 33
Methods to encourage good sleep hygiene include:

  • Keeping regular sleep hours (i.e., go to bed and wake up at the same time every day).
  • Avoiding stimulants (e.g., coffee, chocolate, caffeinated and/or carbonated beverages), especially in the hours before bedtime.
  • Creating an environment conducive to sleep (e.g., turn off inside and outside lights, control surrounding noise and temperature).
  • Resolving problems and daily concerns before bedtime or make a list for the next day.
  • Incorporating regular physical activity into the day, preferably more than four hours before bedtime. 59

Nicotine replacement therapy (NRT)

NRT options are available over-the-counter as a smoking cessation aids and come in various forms, including gum, patches, and lozenges. The most recent data suggests that using NRT is no more harmful and is probably safer than continuing to smoke during pregnancy. 60 Discussion with health care provider is recommended.

For more information about NRT, see the Smoking file.

Diethyltoluamide (DEET)

Mosquito bites and ticks may have negative consequences during pregnancy by transmitting diseases such as West Nile virus. 61 When used according to manufacturer’s instructions, DEET is an effective way to prevent mosquito bites and ticks. 62 Although this product is recognized as low toxicity, the current research is limited in its use during pregnancy. It is suggested that pregnant women avoid, if possible, situations where they may be exposed to mosquitoes or ticks. 63

For more information about DEET, see the Safety during Pregnancy file.


Sunscreen absorption is subclinical and, therefore, safe to use during pregnancy. 64

For more information about sunscreen, see the Safety during Pregnancy file.

Over-the-counter medication and breastfeeding

Most OTC medications pose no risk to the baby. There are some medications that should be limited or avoided while breastfeeding.

The following are some basic guidelines for taking OTC medicines for breastfeeding women:

  • Take oral medicines after breastfeeding or before the baby’s longest sleep period. This may give the medicine a chance to leave the system before breastfeeding the baby again.
  • Acetaminophen and NSAIDs usually provide safe pain relief for women who are breastfeeding. 20
  • Avoid using aspirin because it can cause rashes and bleeding problems in nursing babies. Aspirin-containing medications also create an increased risk of Reye syndrome. Aspirin should not be the first choice for pain relief for breastfeeding mothers. 20
  • Limit long-term use of sedating antihistamines. Antihistamines will pass into breastmilk but not likely at high enough levels to cause clinical effects. Sedating antihistamines cause side effects in nursing babies such as drowsiness. Breastfeeding women should ask their health care provider or pharmacist before taking OTC medication. 52
  • Pseudoephedrine is used as a nasal decongestant. Although it is excreted into breastmilk in low levels, caution should be used with this product as it may reduce milk production in late-stage lactation (i.e., mothers who are breastfeeding infants older than eight months of age). 65

Herbal Products

Consequences of using herbal products during pregnancy

There are many factors to consider before using herbal products during pregnancy. The safety and effectiveness of most herbal products during pregnancy has not been established. 66,67 Natural health products (NHPs) sold in Canada are subject to the Natural Health Products Regulations, which came into force on January 1, 2004. To be legally sold in Canada, natural health products must have a product licence. The Canadian sites that manufacture, package, label, and import these products must have site licences. 68 A licensed product has an eight-digit NPN or DIN-HM number. Not all products sold in Canada have gone through evaluation yet these products receive an exemption number and can also be legally sold in Canada.

The concentration of active ingredients in herbal products can vary considerably from product to product. 69 The active ingredients may cross the placenta into the baby, and the effects on the baby are largely unknown. It is recommended that before taking any herbal products a woman consult her health care provider to discuss risks and benefits. 20,69

See the table 2 for more information about commonly used herbal products.

Table 2: Common herbal products, their uses and effects, and potential consequences for mother and baby

Herbal product Uses and adverse effects Potential consequences for mother and baby
Aloe vera, topical and oral Topical treatment for:

  • Wounds.
  • Burns.
  • Other skin conditions. 69

If taken orally aloe vera can cause severe nausea and vomiting. 69

Some reports have suggested if taken orally aloe vera may cause:

  • Uterine stimulation.
  • Pregnancy loss
  • Preterm labour. 70
Black cohosh Used to lessen:

  • Menopausal symptoms
  • Premenstrual syndrome symptoms.
  • Painful menstruation symptoms. 20,69
  • May cause hypotension for some women. 20
May cause:

  • Preterm labour.

Black cohosh should be avoided during pregnancy. 67

Chamomile Used to:

  • Calm an upset stomach.
  • Help with sleeping problems.
  • Treat skin conditions.

No side effects are noted.

No serious adverse events have been reported in pregnant women who drink chamomile tea. 67
Cranberry supplements Used to:

  • Prevent urinary tract infections. 71

No side effects are noted.

There are no concerns for baby if cranberry supplements are used during pregnancy at the recommended doses. 71
Echinacea Used to:

  • Treat the common cold, sore throat, and other upper respiratory tract infections. 72

No side effects are noted.

The limited data available does not suggest concerns for baby. 67
Fenugreek Potential side effect noted:

  • Diarrhea
  • Maple syrup odour in urine and sweat. 20,67
May cause:

  • Uterine contractions.
  • Miscarriage.
  • Early labour. 18
  • Low blood 73
  • Blood-clotting 73

For these reasons, fenugreek is not recommended during pregnancy.

A small amount of fenugreek used in food preparation is likely safe during pregnancy. 20

Ginger Used to:

  • Treat nausea and vomiting during pregnancy. 74,75

No side effects are noted

There are no concerns for baby. 75
Gingko biloba Used to:

  • Assist with memory. 20

May cause:

  • Headache
  • Dizziness
  • Heart palpitations.
  • Stomach upset.
No information for use during pregnancy.
Ginseng Used to:

  • Increase mental focus.
  • Stimulate immune system. 20,67

May cause:

  • Hypoglycemia. 20,67
The limited safety information available does not suggest an increased risk for adverse pregnancy outcomes with use of Panax ginseng. 20,76 There is no information available for Siberian Ginseng.
Glucosamine Used to:

  • Treat symptoms of arthritis. 77

May cause:

  • Nausea and vomiting.
  • Drowsiness
  • Headache
  • Rash
  • Exacerbation of asthma symptoms. 77
The limited safety information available does not suggest an increased risk for adverse pregnancy outcomes with use of glucosamine. 77
Raspberry leaf Used to:

  • Shorten the duration of labour. 78

No side effects are noted.

The limited safety information available does not suggest an increased risk for adverse pregnancy outcomes with use of raspberry leaf.
St John’s wort Used to:

  • Treat mild or moderate depression. 20,67

May cause:

  • Dry mouth
  • Dizziness
  • Constipation
  • Interactions with other medications.
  • Confusion. 20
May cause:

  • Low birth weight.
  • Decreased absorption of iron. 20

Herbal products and breastfeeding

Breastfeeding women should be very careful about herbal products, especially when the baby is a newborn or premature. 69 Like conventional medicines, certain herbal products may transfer into the breastmilk. 69 Some herbal and traditional medicines may be harmful to the baby while others can affect the breastmilk production. 20, 69 Most herbal products do not have enough documented information to determine their safety in breastfeeding and the concentration of active ingredients may vary.

See the table 3 for more information about herbal products and their effect on breastfeeding.

Table 3: Common herbal products and their effect on the breastfeeding mother and/or baby

Herbal product Effect on the breastfeeding mother and/or baby
Aloe vera topical
  • Sometimes used to help heal cracked nipples, but not recommended due to the bitter taste and the need to be removed prior to feeding
  • May cause a baby to have diarrhea. 20,69
Black cohosh
  • May reduce breastmilk production. 20,69
Blessed thistle
  • Often used to increase milk supply although there is no evidence-based research to support this claim. 20,69
  • Considered safe to use in weak concentrations (e.g., tea). 20,69
  • Considered safe to use at the recommended doses. 20,69
Echinacea May cause a baby to have:

  • Diarrhea.
  • Poor feeding.
  • Skin rashes. 20,69
Evening primrose oil
  • Limited information but considered safe to use at the recommended doses. 20,69
  • May increase milk supply.
  • Reports of colic/abdominal discomfort, diarrhea, and maple syrup odour in urine of the baby have been noted. 20,69
  • Considered safe to use at the recommended doses. 69
Gingko biloba
  • Limited information available so currently not recommended. 69
  • Limited information available so currently not recommended. 69
St John’s wort
  • During lactation, St. John’s wort should be used with caution due to potential side effects of colic, drowsiness, and lethargy. 79

Recreational or Street Drugs

Categories of recreational or street drugs

Recreational or street drugs act as disruptors, stimulants or depressors on an individual’s central nervous system. The following table shows a comparison of the categories of recreational or street drugs based on their effects on the central nervous system.

Table 4: Categories of recreational or street drugs80,81

Disruptors Stimulants Depressants
Disrupt an individual’s mental functions including:

  • Perception
  • Mood
  • Cognitive process
Stimulate an individual’s mental functions by:

  • Increasing alertness
  • Accelerating mental process
  • Increasing energy.
Slow down an individual’s mental functions by:·

  • Reducing alertness.
  • Increasing relaxation.
  • Decreasing awareness.

  • Cannabis (also known as marijuana, weed, hash, pot, grass, joint, reefer, Mary Jane).
  • Hallucinogens (e.g., LSD, MDMA, ecstasy).

  • Cocaine (also known as freebase, coke, powder).
  • Amphetamines (also known as speed, peanut, wake-up).
  • Methamphetamine (also known as ice, crystal meth).

  • Opiates (heroin, methadone, codeine, morphine, opium).
  • Gamma-hydroxybutyrate (GHB) (also known as liquid X, salty water).
  • Volatile substances (e.g., glue, solvents).

Prescription drug misuse is on the rise.83 Prescription drug misuse most commonly refers to the misuse of opioids (i.e., natural and synthetic derivatives of opium). Canada had the highest per capita consumption of oxycodone (a prescription opioid) in the world.82 Opioids (e.g., morphine and codeine) are medications that are used to treat acute and chronic pain. The risks of prescription drug misuse to maternal and fetal health are dependent on the type of prescription medication and timing of exposure during pregnancy.83

Consequences of recreational or street drugs for pregnant women

Drug use may be associated with different social and health problems for pregnant women such as:

  • Sleep disorders.
  • Physical health problems (e.g., cardiovascular problems, high blood pressure). 84
  • Infections (e.g., HIV/AIDS, hepatitis).
  • Inadequate medical or prenatal care. 85
  • Mental health issues.
  • Psychosocial problems (e.g., financial problems, domestic violence, relationship breakdown). 84,85

Drug use may adversely affect parenting skills (e.g., physical or emotional unavailability, inconsistent care) and the development of the child’s attachment. 86,87 An infant who was exposed to drugs during the end of pregnancy may have withdrawal symptoms (e.g., irritability, crying, insomnia) in the first days to weeks and be more difficult to console. This, in turn, may increase the mother’s stress level and reduce her desire to interact with her baby. 24 Some pregnant women who use drugs do not have access to suitable role models who can guide them in their role as mothers. These women may require more support and guidance in their parental role and in developing an emotional bond with their child. Alternatively, for some women a pregnancy may be a turning point in their life and provide an impetus to make positive life changes.

Consequences of recreational or street drugs for pregnancy and/or baby

Women who use drugs have higher-risk pregnancies owing to potential adverse effects on the unborn child. 88

Drugs (especially those with a high potential for dependence, such as cocaine or opiates) may cross the placental barrier and affect certain aspects of fetal development. 8, 24 The effects of drugs on the fetus and long-term child development are contradictory and have many confounders. 85

Methadone maintenance treatment is considered the standard of care for women who are pregnant and dependent on opioids. The potential benefits include:

  • Safer, medically supervised opioid use (stable supply, pure quality, no fluctuating blood level, no exposure to contaminants).
  • Better antenatal care.
  • Increased fetal growth.
  • Reduced fetal mortality.
  • Increased likelihood of carrying pregnancy to term.
  • Fewer birth complications.
  • Decreased risk of transmission of HIV (and potentially HCV and other blood-borne pathogens) (including decreased risk of transmission of HIV to infants).
  • Decreased cases of preeclampsia and neonatal abstinence syndrome.
  • Increased likelihood that infant will be discharged into his or her parents’ care.
  • Increased retention in treatment.122, 123

The most frequently reported effects of drug use during pregnancy on the unborn baby are set out in the following table.

Table 5: Possible effects of recreational or street drugs on a woman’s pregnancy and/or baby

Recreational or street drug Possible effects on a woman’s pregnancy and/or baby
  • Effects are not clearly demonstrated. 8,89,90
  • Although data is conflicting, cannabis exposure has been associated with low birth weight, preterm labour, and effects on long-term neurodevelopment. 91
  • Newborns may experience adverse effects at birth such as tremors. 90
  • Effects will be confounded by other factors that often go along with cannabis use such as cigarette smoking. 8
  • Intrauterine growth restriction (IUGR). 37
  • Increase in the number of uterine contractions. 85,86,92
  • Placental vasoconstriction. 85,86
  • Placental abruption. 85,86
  • Pre-eclampsia. 92
  • Premature rupture of the membranes. 85,86
  • Miscarriage. 8
  • Preterm delivery. 85,86
  • Low birth weight. 85,86
  • Mild withdrawal symptoms at birth. 85,86
  • Sudden Infant Death Syndrome (SIDS). 8,37,93
  • Long-term neurodevelopmental and cognitive deficits. 92
  • Effects will be confounded by sociodemographic and maternal risk factors such as socioeconomic status, alcohol, and other drug use. 92
Amphetamines and methamphetamines
  • IUGR. 94
  • Premature delivery and low birth weight. 8
  • Long-term developmental effects. 37
  • Withdrawal symptoms at birth. 37
  • Effects will be confounded by other factors such as cigarette smoking, alcohol, and other drug use. 94
Opioids (except methadone/ buprenorphine)
  • IUGR. 8,86
  • Placental abruption. 85
  • Miscarriage, stillbirth, preterm delivery. 8,85
  • Low birth weight. 8,85
  • Neonatal abstinence syndrome (NAS). 8,85
  • SIDS. 8,85

Factors affecting the health consequences of drug use

Based on current scientific data it is not possible to determine whether the effects of maternal drug use on an unborn baby are caused directly by the substance itself or by exposure to other health-harming factors. 86,95

Few studies have measured the influence of confounding factors often associated with drug use, such as:

  • Patterns of use (e.g., product quality; dose taken; administration route used [oral, nasal, injection]; frequency of use; stage of fetal development at the time of use). 95
  • Polydrug use. In most cases of drug use, drugs are used in combination. For example, it has been documented that 93 percent of pregnant women who used cocaine or heroin also used other substances (primarily alcohol and tobacco) with harmful effects on the health of their baby. 96
  • Maternal traits (e.g., overall health; genetic and physiological factors that lead to individual differences in metabolism; and physical and psychological tolerance for drugs). 97,90
  • Socioeconomic factors and living conditions (e.g., malnutrition, lack of prenatal care, lack of financial resources, underprivileged neighbourhood, criminality, prostitution). 85,90

Whether a drug’s effects on an unborn baby are caused directly by the substance and/or by the influence of the above confounding factors, it is strongly recommended that women not use drugs while pregnant because of the risk to the unborn child. Some drugs such as opioids may require a gradual weaning as sudden stopping can trigger uterine contractions at all stages of gestation. 98

Recreational or street drug use before a woman knows she is pregnant

If a woman used drugs before she knew she was pregnant and is concerned about having harmed her baby’s development, reassure her by reminding her that drug use during pregnancy comes with potential, not automatic, risks to the pregnancy and unborn child. Furthermore, the quality of the environment in which the child grows up is important. Other factors in the child’s environment may offset certain effects of the drugs, such as the mother’s healthy lifestyle; a stimulating, warm family environment; or a quality mother-child relationship.

Still, drug use is never risk-free. Therefore, it is highly recommended that women seek professional advice to safely quit using drugs. To stop using opioids, alcohol, and benzodiazepine medical detoxification will be required.

For further information regarding treatment options for recreational or street drug addiction, please see Appendix B.

Recreational or street drugs and breastfeeding

Drugs may appear in breastmilk and interfere with production, quantity, and/or composition. Infant exposure to drugs through breastmilk has been associated with adverse health effects as shown in the following table.

Table 6: Possible effects on infants breastfed by mothers who use drugs

Drugs Possible effect on the nursing infant
  • Lethargy 8,99
  • Reduced muscle tone. 8,99,100
  • Irritability 8,99,100
  • Limited data has shown neurodevelopmental consequences for a baby. 101
  • Increased risk of SIDS. 101
  • Irritability. 8,20
  • Vomiting. 8,20
  • Diarrhea. 8,20
  • Tremors, convulsions. 8,20
  • Tachycardia. 8,20
  • High blood pressure. 8,20
  • Irritability. 102
  • Sleep disturbances. 102
Heroin and opioids
  • Withdrawal symptoms. 8,37
  • Agitation. 8,37
  • Tremors. 8,37
  • Vomiting. 8,37
  • Drowsiness. 8,37
  • Feeding problems. 8,37

Because of the potential for harm, it is advised that a breastfeeding mother not consume any recreational or street drugs.

The exposure of infants to methadone through their mothers’ breast milk is minimal. Women using methadone for treatment of opioid dependence should not be discouraged from breastfeeding. The benefits of breastfeeding largely outweigh any theoretical minimal risks.124

For further information regarding treatment options for recreational or street drug addiction, please see Appendix B.


When to refer

Women would benefit from a referral to the appropriate health care provider if they:

  • Have an existing medical condition.
  • Are taking prescription medication.
  • Are taking over-the-counter medication or herbal products and have not consulted with their health care provider.
  • Disclose recreational or street drug use.

Where to refer

Women who need more information about the use of prescription, over-the-counter, and herbal medications during pregnancy and while breastfeeding may be referred to:

  • Their local pharmacist.
  • Telehealth Ontario at 1-866-797-0000.

Women who need more information about the use and treatment of alcohol, tobacco, recreational or street drugs during pregnancy and while breastfeeding may be referred to:

Note, substance use by a caregiver is reportable. In cases where a woman continues to use recreational or street drugs while pregnant and/or parenting, Children’s Aid Society should be notified. The Ontario Association of Children’s Aid Societies provides protective services to infants and children through one of its 46 Societies.

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Resources & Links

Please note this is not an exhaustive list of available resources, nor should any of these resources be used in place of seeking professional advice. The resources cited throughout this resource are not necessarily endorsed by the Best Start Resource Centre or the Government of Ontario. When in doubt, professionals should contact the organization responsible for issuing a specific recommendation/practice guideline.

Professional Guidelines

Professional Associations



  • ConnexOntario at 1-866-531-2600
  • Telehealth Ontario 1-866-797-0000

Prenatal Education Provider Tools

Client Resources and Handouts


  • Koren, G., (2007). Medication Safety in Pregnancy and Breastfeeding: The Evidence-Based A to Z Clinician’s Pocket Guide. Toronto, Ontario. McGraw-Hill Medical.
  • Hale, T., (2014). Medications & Mothers’ Milk. Amarillo, Texas. Hale Publishing.
  • Koren, G. (2004). The Complete Guide to Everyday Risks in Pregnancy and Breastfeeding: Answers to All Your Questions about Medications, Morning Sickness, Herbs, Diseases, Chemical Exposures and More. Toronto, ON: Robert Rose Publishers
  • Millis, J.J., Dugoua, D., Perri, D., & Koren, G. (2006). Herbal Medicines in Pregnancy and Lactation: An Evidence-Based Approach. Taylor & Francis, Toronto, Canada.
  • Ordean, A., Midmer, D., Payne, S., Hunt, G., (2008). Pregnancy-Related Issues in the Management of Addictions: A Reference for Care Providers. Toronto, Canada. Department of Family and Community Medicine, University Of Toronto.


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Appendix A: Common maternal medical conditions, effects on pregnancy/infant, and safety considerations for prescription medication in pregnancy

Medical condition Effects of medical condition on pregnancy/infant Safety considerations for prescription medication in pregnancy
Depression Women who receive adequate treatment for their depression are shown to have:103

  • Increased participation in prenatal care.
  • Decreased likelihood of using recreational or street drugs and alcohol.
  • Decreased risk of self-harm.
  • Increased capacity for positive, early infant interactions.
  • Decreased rates of developing perinatal mood disorders.
  • Increased breastfeeding initiation and duration rates.

Untreated or undertreated maternal depression/anxiety increases the risk of:

  • Miscarriage.
  • Pre-eclampsia.
  • Pregnancy-induced hypertension.
  • Preterm delivery.
  • Admissions to a neonatal intensive care unit.103, 104
  • Lower breastfeeding initiation rates and increased maternal/infant attachment issues.105
Some antidepressants have been researched more than others, and most have not been linked with a higher risk for birth defects.22,104 Some antidepressants taken during the third trimester may be associated with a condition called poor neonatal adaptation syndrome (PNAS) which includes infant irritability, sleep disturbance and low tone. This condition is transient with no long-term effect.106
Hypertension Women who receive adequate treatment for their hypertension are shown to have:107,108

  • Lower risk of maternal morbidity and mortality due to stroke and/or heart disease.

Experts agree that blood pressure medication should be given to pregnant women with severe hypertension to protect them from a stroke. However, whether there are benefits to treating pregnant women with mild-to-moderate hypertension is controversial. Canadian obstetricians are divided on how to treat hypertension.108

Chronic maternal hypertension may put a fetus at increased risk of:108

  • Intrauterine growth restriction.
  • Prematurity.
  • Intrauterine death.
The majority of antihypertensive medications have not been associated with an increased risk for major malformations.109Some treatments for hypertension such as certain beta-blockers may increase the risk for small-for-gestational-age infants.108
Epilepsy Women who receive adequate treatment for epilepsy are shown to have:110

  • Decreased chance of injury from seizure.
  • Decreased chance of miscarriage and stillbirth.
  • Decreased chance of premature labour/birth.

Epilepsy itself is no risk to the developing fetus.26

Studies have shown that women on antiepileptic drugs have about two or three times the risk of having a child with major malformations compared with women without epilepsy. Some anti-epileptic medications such as valproic acid are more of a concern than others.26
Rheumatoid Arthritis (RA) Rheumatoid arthritis itself doesn’t seem to harm the developing baby, even if it is active during pregnancy. In fact, 70 percent to 80 percent of women with RA have improvement of their symptoms during pregnancy.111Although some women may have a slight risk of miscarriage or low-birth-weight babies, the vast majority of women have normal pregnancies without complications.111 Prenatal exposure to nonsteroidal anti-inflammatory drugs increases the incidence of pulmonary hypertension and/or premature closure of the ductus arteriosus when used in the third trimester.39
Diabetes Women with pre-gestational diabetes who maintain glucose levels within a normal range are shown to have less risk of having:112

  • An infant with birth defects.
  • A large-for-gestational-age baby.
  • A preterm birth.
  • A caesarean birth.
  • A miscarriage or stillbirth.
  • An infant with respiratory distress syndrome and low blood sugars.
  • Symptoms of hyper or hypoglycemia including, fatigue, dizziness, headache, and confusion.
If glycemic targets are not achieved within two weeks of nutritional therapy alone, insulin therapy should be initiated.113For women who refuse insulin, glyburide or metformin may be used as alternative agents for glycemic control. However, both agents cross the placenta, and long-term safety data are not available.113
Asthma Women who receive adequate treatment for their asthma are shown to have less risk of:114

  • Wheezing and shortness of breath.
  • Developing hypertension and/or pre-eclampsia.
  • Placental problems.
  • Preterm labour.
  • A caesarean birth.
  • A low-birth-weight baby.
Most asthma treatments are safe for women to use when pregnant.114Fast-acting inhalers (e.g., albuterol) and inhaled corticosteroids are considered preferred treatments for asthma during pregnancy.Compared to oral medicines, inhaled medications are absorbed into the body in lower amounts. Therefore, less of the medication should reach the developing fetus.114
Urinary tract infection (UTI) Women who receive adequate treatment for a UTI are shown to have less risk of:115

  • Discomfort related to UTI symptoms.
  • Preterm labour.
  • Chance of the UTI progressing into pyelonephritis.
  • A low-birth-weight baby.
There are antibiotics used for UTIs that when used during pregnancy have not been associated with an increased risk of major birth defects.115
Nausea and vomiting of pregnancy (NVP) Women who receive adequate treatment for their nausea and vomiting are shown to have less risk of:74

  • Disruption to their activities of daily living, including parenting, working, and socializing.
  • Increased stress.

Mild NVP is not usually harmful to your baby.74

In severe cases (e.g., hyperemesis gravidarum), treatment will result in less malnutrition, dehydration, and hospitalizations.

In Canada, doxylamine-pyridoxine (Diclectin®) is an example of a prescription drug available for the treatment of NVP.116Pregnant women may take an antiemetic drug such as dimenhydrinate (Gravol®) on the advice of their doctor.

Drugs that have shown to be effective with no risk to the development of the pregnancy have been studied.117

Human immunodeficiency virus (HIV) Studies indicate that pregnancy does not harm the health of women with HIV infection or increase the chance of women developing HIV-related illnesses.118Without any prevention strategy, the risk of mother-to-child transmission is about 25 percent. However, if prevention strategies begin in sufficient time, this risk can be reduced to 1 percent.118 Until now, no major problems have been identified in fetuses exposed to antiretroviral drugs. However, evidence is limited.118

Appendix B: Treatment Options for Recreational or Street Drug Use

Harm reduction

The vast majority of women who use recreational or street drugs quit using drugs or cut back when they find out they are pregnant. Although it is strongly recommended that women quit using drugs completely during pregnancy, not every woman will choose or be able to do so.119 Harm reduction may prove to be a more appropriate solution for these women. The aim of this approach is to reduce the harmful consequences of drug use rather than to completely eliminate the drug use itself. As such, it provides a certain number of benefits and a certain level of risk reduction for the expectant mother and her unborn baby.96

Methadone/buprenorphine maintenance treatment

Methadone is a doctor-prescribed medication used to treat opioid addiction.120 It is indicated for pregnant women with an opioid use disorder. Sudden discontinuation of opioids during pregnancy may lead to severe withdrawal which is associated with a risk of uterine contractions increasing the risk of premature delivery or miscarriage. Methadone maintenance treatment is used to stabilize the pregnant woman’s condition and to help her reduce/quit using drugs.121

Taking methadone during pregnancy may be associated with smaller birth parameters and withdrawal symptoms in the newborn. However, the benefits of methadone outweigh risks of continued drug use; it does not produce euphoric effects, but acts to significantly reduce cravings, keeps the mother functional and promotes better prenatal care.84,121

Methadone therapy is currently the gold standard for managing opioid dependence during pregnancy. However, when access to a methadone clinic is not available, or a woman refuses methadone treatment, buprenorphine is an alternative opioid replacement treatment.82

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