Be prepared before labour starts.
Labour typically begins between the 37th and 42nd week of pregnancy. It is a natural, physiological process that usually begins when you and your baby are ready. Plan to wait for labour to start naturally unless medical concerns arise. It is best to be prepared for whenever your labour might begin. Being prepared can increase your confidence in your ability to cope with labour and give birth.
To prepare for labour, you can:
- Learn about the process of labour and birth.
- Think about comfort measures you want to try as you move through the stages of labour and talk about these with your support person(s) and health care provider(s).
- Pack a bag with the things you will need during labour and after the birth.
- Make a list of contact numbers, including your support person(s), your health care provider(s), and your hospital or birthing centre.
- Make a transportation plan so you will be able to go the hospital or birth centre quickly when needed.
- Collect supplies recommended by your midwife if you are planning a home birth.
Watch for early signs of labour in the last few weeks of your pregnancy.
During the weeks leading up to labour, you may experience signs that labour will begin soon. Signs that labour can begin soon include:
- An easier time breathing due to your baby moving further down into the birth canal, which leads to lessening pressure on your lungs. This is called lightening.
- Increased vaginal discharge or the loss of your mucous plug.
- Irregular cramping or Braxton Hicks contractions.
- A sense of renewed energy.
These signs do not mean you are in labour. They are signs that labour may begin within the next couple of days or weeks. When you experience these signs, listen closely to your body as it prepares for labour.
The start of labour is marked by strong, regular contractions and/or the rupture of your membranes. If you have either or both of these signs, contact your health care provider.
If you have strong, painful contractions that occur regularly (e.g., every five minutes and lasting for almost one minute), your labour may have begun. Your support person(s) can help time your contractions. Labour contractions cause your cervix to shorten and thin (efface) and widen (dilate) getting ready for the birth of your baby.
The bag of water that your baby is in may also break open, signalling the start of labour. This is known as the rupture of membranes . When this bag of water breaks, you may experience a large gush of fluid or a steady trickle of fluid. If you think that you may be leaking fluid, contact your health care provider.
It is important to record the:
- Time when the bag of water broke.
- Amount of the fluid.
- Colour of the fluid.
- Odour of fluid.
You can use the acronym TACO to remember this.
The fluid is normally clear but occasionally may look pink due to bleeding caused by changes in the cervix; this is okay. If the fluid is dark or green in colour, go to the hospital right away. If there is a large amount of bright-red bleeding, call 911 for an ambulance to take you to the nearest hospital.
If you are Group B Streptococcus (GBS) positive, you will also need to go to the hospital right away or call your midwife once your bag of water breaks, so you can receive antibiotics.
It is normal for labour to last longer for some women than for others.
The experience of labour and how long it lasts is different for every woman and every pregnancy. Learning about the three stages of labour will help you understand the progress of your labour, what to do, and how to best to comfort yourself.
During the first stage of labour, your cervix needs to dilate from 0 cm to 10 cm.
During pregnancy, your cervix is closed. During labour, your cervix widens (dilates) to 10 cm to allow for the birth of your baby. Dilation occurs during the first stage of labour. The first stage of labour is divided into the following three phases: early labour, active labour, and the transition phase.
During early labour, your cervix will first soften and shorten. If this is your first baby, early labour moves into active labour once you reach 3 â 4 cm of dilation. If you have given birth before, this happens at around 4 â 5 cm of dilation. Many women find this phase to be especially long. Try to move around, drink, eat healthy snacks, and rest during this phase.
During the active phase of labour, your cervix will continue to dilate to 8 cm. Your contractions will become stronger, closer together, and last longer. This is often the phase when women rely heavily on their support system and may ask for pain medication. Most women are admitted to the hospital during the active phase of labour if they are planning a hospital birth.
During the transition phase of labour, your contractions will become even closer together and last longer as your cervix completely dilates from 8 cm to 10 cm. This is a short phase, but it is often the most challenging phase for women. Remember that the contractions are strong because your baby is coming.
During theÂ second stage of labour, pushing occurs. This is when your baby will be born.
When your cervix is 10 cm or fully dilated, you may start to feel the urge to push. You should not begin to push until you are fully dilated and feel the urge to push. The length of this stage can vary among women. It can take up to two to three hours or longer, especially if you do not feel a strong urge to push. It may be shorter for women who have had a baby before.
When pushing, listen to your body, use positions that feel are best for you, and push when you feel the urge to push. It is also important to listen to the guidance of your health care providers. They may suggest positions for pushing and when to stop pushing.
During the third stage of labour, the placenta will come out.
Not long after your baby is born, you will feel some mild contractions again and you will then be able to push out the placenta. This is usually a quick process. If the placenta does not come on its own, your health care provider may need to remove it for you.
Learn more about labour progress.
You can find out more about the stages of labour and ways in which to cope with labour from the following resources. More suggestions can be found in the Resources and Links section.
- Your health care provider
- Your local public health unit 1-866-532-3161.
- Prenatal classes.
- Society of Obstetricians and Gynaecologists of Canada (SOGC): Pregnancy Info
About Labour Progress
Labour is a natural, physiological process1 normally occurring at the end of a woman’s pregnancy.2 It begins with regular, painful uterine contractions and/or the rupture of the membrane of a woman’s amniotic sac (commonly referred to as one’s “water breaking”), and it ends with the birth of her baby and the placenta.1,2,3
Distinct physiological changes tend to occur to a woman’s body in a sequential order throughout labour. As such, labour is often divided into stages. Dividing labour into stages can be helpful in assisting women to understand and cope with the changes that occur to their body during labour as well as anticipate the changes yet to come.3,4,5
Although the main events of labour are generally the same for each woman, it is important to note that the onset of labour as well as the duration of labour varies widely among women.1,2,3,6,7
Variability in the onset of labour
Labour typically occurs between 37 and 42 weeks’ gestation for both primigravidas and multiparous women.1,2 Labour will generally begin when a fetus is mature and a woman’s body is ready, but the spontaneous onset of labour cannot be accurately predicted.1,6 Calculating a women’s estimated due date is best done with an ultrasound between 7 and 16 weeks’ gestation. Using Naegele’s ruleultrasounds after 16 weeks and abdominal measurements are all highly variable.1,6 It is best to tell expectant women that one cannot accurately predict the actual date that their labour will begin but that there are early signs of labour that they should watch for which can indicate that their labour may begin soon.1,3
Variability in the duration of labour
The duration of labour is also variable and can be longer for primigravidas.2,7 It can be helpful for women to know this as well as to understand that although their labour progress will be monitored, there is no way to predict how long it will last. Throughout active labour, a health care provider monitors labour progress by assessing:
- Cervical dilation in centimeters and the fetus’ station during vaginal examinations. The expected rate of cervical dilation is 0.5 cm per hour over a four-hour period.
- Frequency, duration, and strength of contractions.
Some women can get preoccupied with numbers and feel discouraged if they do not think they are making enough progress in a certain amount of time. If all is well with the mother and the fetus, the rate of cervical dilation can be appropriate at 0.5 cm per hour or even 0.3 cm per hour.7 Overall, the key message for women should be that all women are different and sometimes labour naturally takes longer for some than for others. The best thing for a woman in labour to focus on is herself and her baby.2,3,7
In 2006, it was estimated that 73.7 percent of the women who gave birth in Canada did so vaginally. Of this percentage, 61.1 percent required no assistance with the birth and 11.9 percent gave birth vaginally but required some assistance (i.e., with the assistance of a vacuum, forceps, or both).8 See the file on Interventions in Labour for more information on assisted vaginal births. In 2006, it was estimated that 26.3 percent of women delivered their baby via a caesarean birth. 8 See the Caesarean Births file for more information on this topic.
Preterm births are defined as those that occur at less than 37 weeks’ gestation. Babies born preterm have increased morbidity and mortality rates than those born at term. Between 2006 and 2010 in Ontario, the number of preterm births decreased slightly from 8.4 preterm births per 100 live births to 7.9 preterm births per 100 live births. During this same time period, very preterm births (i.e., those occurring at less than 32 weeks’ gestation), remained relatively stable at 1.2 live births per 100 live births.9
Postterm births are defined as those that occur after 42 weeks’ gestation. These pregnancies have an increased risk of perinatal mortality, morbidity, and operative birth. Between 2006 and 2010 in Ontario, the number of postterm births remained relatively stable at approximately 0.3 births per 100 live births.9
In 2006, it was estimated that 97.9 percent of the births in Canada occurred in hospitals or clinics, 1.2 percent of births took place in a private home, and 0.8 percent took place in a birthing centre. Birthing centres are community-based centres where women can receive midwifery care during pregnancy, labour, birth, and the postpartum period. Birthing centres are distinct from home and hospital settings, but it should be noted that some providers sometimes still refer to maternity units within hospitals as birthing centres. Currently, the majority of births occur in a hospital. It was found that out-of-hospital births were more common among multiparous women (2.7 percent) and women over 35 years of age (3.6 percent). In most circumstances, the setting for the birth has been typically planned in advance, but some births have taken place in unplanned settings such as en route to a care setting.8
Distance to birth location
As Canada is the second largest country in the world in addition to having a geographically-dispersed population, some women travel to another location to give birth. This can be due to care needs or due to a personal choice (e.g., epidural availability). In 2006, 22.8 percent of women living in Ontario reported travelling to another city, town, or community to give birth. Working with women and families from rural and remote places requires special consideration. Discussion during pregnancy of the potential financial and psychological stress with relocation is an important part of planning for labour and birth.8
In 2006 in Canada, 69.6 percent of women reported that their primary birth attendant was an obstetrician/gynaecologist, 14.6 percent reported that their primary birth attendant was a family physician, 4.7 percent reported that their primary birth attendant was a nurse/Nurse Practitioner, and 4.3 percent reported that their primary birth attendant was a midwife. From these statistics, it was reported that 49.4 percent of women had the same care provider during their pregnancy, labour, and birth. A majority of women (88.4 percent) stated that having the same care provider during their pregnancy and during their labour and birth is important to them.8
Who is at Risk?
Most women start labour expecting to give birth vaginally.3,4,10,11,12 Some circumstances can occur during labour, however, that can either slow down or stop the process of labour. Such circumstances can involve issues with the following:4,10
- The power.
- The passenger.
- The passageway.
- The psyche.
Uterine contractions are responsible for causing cervical effacement, cervical dilation, and descent of the fetus. Inadequate contractions are the most common reason for labour to slow down or to stop. This can occur if the contractions are inadequate in strength, frequency, or duration.4,10
The number and the position of the passenger(s) can have an impact on the process of labour. If, for example, a woman is carrying twins, and one twin is a position that is difficult to fit through a woman’s birth canal, the labour process may slow down or stop.4,10
If the birth canal of a woman is too narrow or is somehow asymmetrical, the labour process may slow down or stop. This issue is rare, but a woman is at a higher risk of this occurring if she is of a short stature (<155 cm), if she has previously injured her pelvis, or if she has a bony or soft-tissue tumour in or near her pelvis.4,10,13
Labour progress can depend on a woman’s confidence in her ability to cope with labour pain and to give birth. If a woman does not have this confidence, or fears childbirth, labour progress can be impeded.10,12
Note that many women who have experienced some of the circumstances discussed in this section have been able to successfully proceed through labour and give birth vaginally. Supportive actions such as regularly changing positions and receiving encouragement from a support person can have a positive influence on the ultimate labour outcome. Although it is not possible to continue labour in all circumstances, women should be aware of these coping mechanisms.4 See the Labour Support file for more information on this topic.
If the labour process truly cannot proceed, women will be assisted with their labour and/or birth.3,4 Please see the files on Interventions in Labour and Caesarean Births for more information on this topic.
Preparing for Labour
For most women and their families, labour and birth is a time of excitement and anticipation, but it can also be a time of uncertainty, anxiety, and fear.1,3 One of the best ways to relieve the anxiety and fear that women and their families may face is to adequately prepare them for labour and birth. 12,14,15,16
Antenatal preparation for labour and birth can:
- Decrease people’s fears and anxieties concerning labour and birth.12,14
- Increase women’s confidence in their ability to give birth.15,17,18
- Result in reduced early labour admissions.15
- Result in greater partner involvement.14
- Result in a shorter labour.12
- Increase people’s ability to cope with their birth experiences in the postpartum period.14
- Increase people’s confidence in their ability to breastfeed and care for their baby following birth.16
All pregnant women in Canada should be given information, encouragement, and support about the process of labour and birth.1,2 This can be done through:
- Prenatal classes.
- One-on-one, open discussions with health care providers.
- Discussions with support person(s).
Prenatal education classes provide the opportunity for women and their support person(s) to receive education and learn skills pertaining to pregnancy, labour, birth, breastfeeding, and the postpartum period.18 The information that expectant parents receive in these classes needs to be clear and complete. Expectant parents need to be provided with written as well as verbal information. If the information they receive is vague, conflicting, or incomplete it can heighten rather than decrease anxieties.9
Prenatal education classes also provide the opportunity for women and their support person(s) to receive information on how to prepare for and cope with events that may occur during pregnancy, labour, birth, and the postpartum period. Practicing different labouring positions and breathing techniques in prenatal classes can help women cope with the pain experienced during labour.18
In addition to providing information on the physiological and mental process of labour and birth, prenatal educators may consider providing information on the policies and procedures of hospitals and/or birthing centres in the area. Hospital or birthing centre tours can be offered as part of this education. For expectant parents, being able to actually see their birthing place can greatly ease their anxieties.9
Additionally, meeting with other expectant parents with similar questions is particularly beneficial in relieving anxieties and building a support network. This is something to consider when expectant parents are choosing the format of their prenatal classes, especially with the growing interest in online prenatal education.19
Expectant parents often find it helpful to discuss their individual fears, anxieties, and expectations (as well as the impact of past traumatic events) with the health care provider who will likely be delivering their baby. At this time, health care providers can provide information about the process of labour and birth to facilitate informed decision-making and a positive birth experience.3,14,16
In preparation for labour, women often find it helpful to have practical supplies ready for when their labour begins. This can include a bag packed with what they will need for labour and after the baby is born and a transportation plan if they are planning to give birth in a hospital or birthing centre. Having a list of important phone numbers in a prominent place is helpful.
Women need to take time for themselves prior to labour to mentally prepare for the process. This may involve taking time off work or staying home from social events. This should be supported by professionals and support persons(s).10
In preparation for labour, women and their support person(s) often find it helpful to talk about their fears, anxieties, and expectations for labour and birth. This can help ease anxieties that they might have concerning the upcoming events as well as serve to stimulate discussion surrounding preferred coping measures and the type of support required during labour.3 See the file on Labour Support for more information on this topic.
Early Signs of Labour
During the days and weeks leading up to labour, pregnant women can experience a variety of signs that their labour may begin soon.10, 20
Many women, especially first-time mothers, seek assistance from their health care provider(s) when they experience signs that labour may begin soon. When this occurs, it is important for health care providers to validate their concerns, reassure them that these signs are normal during late pregnancy, and give them verbal and written instruction on the true signs of labour.2,3,6,20
Some early signs of labour include a sensation of lightening, loss of the mucous plug, irregular cramping or Braxton Hicks contractions, and a surge of energy. It is important to note that not all women experience these signs, nor is this an exhaustive list. Women should receive education about what these signs are and what they mean.10,20
Before labour begins, the presenting part (usually the baby’s head) descends into a woman’s pelvis. When this occurs, women often have an easier time breathing as the baby is no longer pushing on their diaphragm. At this time, women may also feel that they need to urinate more often as the baby is now putting increased pressure on their bladder. For other women, the process of lightening can happen so gradually they do not notice any change at all.10
Towards the end of pregnancy, a woman’s cervix begins to soften in preparation for labour. This may cause increased vaginal mucous secretions as well as the loss of a woman’s mucous plug. A mucous plug is a thick, clear mass of mucous generally the size of a quarter. It is not uncommon for it to be tinged with blood. It is essentially the ‘gate-keeper’ to the opening of the cervix. Loss of the mucous plug is not a cause for concern but indicates that a woman may begin labour soon. Not all women will notice the loss of their mucous plug. It may be unnoticed and flushed down the toilet, or it may not be lost until labour begins.10 21
In labour, a woman’s body undergoes strong, regular uterine contractions to allow for her baby to be pushed out of her uterus and through her cervix and vagina to complete the birthing process. During pregnancy, a woman’s uterus may undergo practice contractions in preparation for this. These are commonly known as Braxton Hicks contractions. They are named after an English physician who first described them in 1872. As opposed to contractions which a woman experiences during labour, Braxton Hicks contractions have the following features:10
- They occur sporadically with no real pattern.
- They are often relieved with rest or a change in position.
- They can be uncomfortable but cause no real pain for a woman.
Note that true contractions do not go away. True contractions occur at regular intervals and are painful. If a woman experiences these types of contractions, she should see a health care provider to determine if she is in labour.10
If concerned at all about contractions at any time during pregnancy, women should seek attention from a health care provider as it is important to rule out the onset of preterm labour.22
In preparation for labour, the hormones that a woman’s body releases change. Due to this, some women feel an increase in their energy level and, consequently, want to expend this energy in some way. This is often referred to as ‘nesting’. It is best for women to try to conserve their energy as much as possible so that they will have enough energy for the upcoming task of labour.10
Some additional early signs of labour include: indigestion, nausea, vomiting, diarrhea, and increased perineal pressure. Unless these signs cause undue discomfort for women, they are generally not cause for concern.10
The Onset of Labour
Signs that labour has begun include the occurrence of strong, regular uterine contractions and the rupture of the membrane of a woman’s amniotic sac. Women should be educated on the signs of the onset of labour and be prepared to seek care when they occur.3,10,23 A Labour Decision Tree, found in the Appendix, may help women and their support person(s) decide when it is time to go to their birthing place. It can also be used to initiate discussion between women and their health care provider about the signs of labour and when to contact their health care provider. There also may be individual differences on when to go to the birthing place based on distance, weather, and/or a history of a fast labour.
The uterus is a muscle. Like other muscles, it undergoes periods of contractions (tightening) and relaxation (rest). During labour, uterine contractions are under the control of a hormone called oxytocin. When oxytocin builds up in a pregnant woman’s body, it causes her uterus to contract at regular intervals with increasing intensity. Contractions are purposeful during labour as they cause a woman’s cervix to efface (thin) and dilate (widen) and the fetus to descend further into the birth canal to allow for birth. If a woman feels that her contractions are strong or painful and are occurring regularly and closer together, she should contact her health care provider to determine if her labour has begun.10,22,23
Determining contraction strength
When a woman’s uterus contracts, she can feel her abdomen become tight. With progressive contractions throughout labour, the abdomen will become increasingly tighter. This frequently causes more pain. A woman may be asked to describe the pain intensity that she feels with her contractions on a scale from 0 to 10.10 This may assist the health care provider in assessing how to best support her and/or how well these support measures are working for her.
During each contraction, a woman’s abdomen will be hard to the touch if it is palpated. Throughout labour, a women’s abdomen may be palpated to help determine the strength of her contractions. Using this method, the strength of contractions can be described as mild, moderate, or strong. The following guidelines can be used to determine the strength of a woman’s contractions via palpation:10
- With mild contractions, a woman’s abdomen feels slightly tight, it is easy to indent with one finger, and it feels similar to touching one’s nose.
- With moderate contractions, a woman’s abdomen feels firm, it is difficult to indent with one finger, and it feels similar to touching one’s chin.
- With strong contractions, a woman’s abdomen feels rigid or board-like and it feels similar to touching one’s forehead.
During labour, contractions occur in a wavelike pattern. Each contraction tends to involve a buildup, a peak of intensity, and a relaxing phase with an interval of rest before the next contraction begins (see the diagram below). It is helpful to time contractions to find out if they are regular, and if they are becoming longer and closer together (indicators of the onset of labour). To determine how long a contraction is (duration), one starts timing at the beginning of the buildup of the contraction and stops at the end of the letdown phase. To determine how often contractions are occurring (frequency), one times them from the beginning of one contraction to the beginning of the next contraction. It is not necessary to time contractions continually. It is most helpful to time contractions when there is a change in the labour pattern or the intensity of the contractions and when the membranes rupture.10,11
The onset of labour can also be marked by the rupture of the membrane of a woman’s amniotic sac. This can occur before or after the onset of contractions. When it occurs, women can experience a large gush of fluid or a constant trickle of fluid. Women should always be assessed by a health care provider if they think they may be leaking amniotic fluid. If a woman’s membrane is ruptured for a prolonged period of time before birth occurs, the risk of infection for her and her baby increases.10,24,25
When a woman’s membrane ruptures, she should be encouraged to take note of the time, amount, colour, and odour of the fluid. A useful acronym to remember to do this is TACO. Amniotic fluid is normally clear. Dark or green-coloured fluid may indicate that the fetus has passed meconium (stool). This is not normal. Most newborns pass their first meconium 24 â 48 hours following birth. Typically, some kind of stressor causes a fetus to pass meconium before it is born. If a woman notices that she is leaking dark or green-coloured fluid, she should seek immediate attention from her health care provider.10,26,27,28If she is unable to reach her health care provider, she should not wait but go to the hospital for assessment right away.
If a woman is Group B Streptococcus (GBS) positive or does not know the results of this routine test performed during late pregnancy, and she ruptures her membrane, she should seek immediate attention from her health care provider to receive treatment. The recommendation is to initiate labour and start antibiotics.10,29,30
There is no routine screen to check to see if a fetus has passed meconium in utero during pregnancy. It only becomes apparent after the amniotic membrane ruptures. If a fetus passes meconium in utero, sometimes the fetus is able to adjust with no adverse consequences, however, there is a risk that a fetus will aspirate the meconium at the time of birth causing respiratory distress. Meconium-aspiration syndrome (MAS) is a complication that occurs approximately 10 percent of the time when the fetus has passed meconium. If a woman is leaking meconium, she should be aware that her birth may be attended by health care providers skilled in neonatal resuscitation as a precautionary measure. Most infants recover complete pulmonary function, but MAS is a significant risk factor for future pulmonary disease.10,26,27,28
Group B Streptococcus (GBS) testing and treatment
At 35 to 36 weeks’ gestation, it is recommended that all pregnant women in Canada be tested for the presence of Group B Streptococcus (GBS) in their vaginal and rectal flora. GBS is bacteria, common in many women’s reproductive tract, which poses no risk to their health. If a newborn is exposed to the bacteria during birth, however, he or she can experience a variety of illnesses such as bacteremia, meningitis, pneumonia, or even death. The mortality rate of newborns infected with GBS is 5 percent to 20 percent.
To test for GBS during pregnancy, a woman is asked to swab her vagina and then her rectum; this swab is then sent for culturing. A health care provider may also do this swab during an antenatal appointment. If, from this culture, a woman is deemed to be GBS positive, it is 96 percent predictive she will still be GBS positive at the time of birth.
The Society of Obstetricians and Gynaecologists of Canada (SOGC) guidelines recommend that women, who are GBS positive, receive intravenous antibiotics from the time of active labour until birth. Women with GBS positive urine culture in pregnancy or with an infant previously affected by GBS are considered colonized and are treated during labour as well.
The antibiotics given are sensitive to the strain of GBS that a woman has. One of the mainstay antibiotics used to treat GBS is penicillin. If a woman has an allergy to penicillin, a different antibiotic can be used. Since universal GBS testing and prophylactic treatment was introduced in 2002, the incidence of neonatal disease in Canada and the United States decreased from 1 to 3 per 1000 in the 1990s to 0.35 to 0.5 per 1000.29,30
The Stages of Labour
Unique sequential events occur during the process of labour from the time of its onset to the time of birth of a newborn and the placenta. A woman’s hormones play a key role in directing this natural, physiological process.1 Labour can be divided into different stages. Understanding what occurs during these different stages as well as learning ways in which to cope with the events in each stage can be greatly beneficial for women and their support person(s).4,10
In female anatomy, the cervix is the bottom area of the uterus which attaches to the vagina. The opening between the cervix and the uterus is called the internal os and the opening between the cervix and the vagina is called the external os. For a woman who is not in labour, it is approximately 2 cm to 3 cm long and is closed. In order for a baby to be able to pass from the uterus through the cervix and into theÂ vagina, her cervix first needs to undergo 100 percent effacement (thinning or shortening) and dilation (widening) from 0 cm to 10 cm. Cervical dilation and effacement are assessed through vaginal examination during labour.4,3,10
Vaginal examinations are performed by trained maternity health care providers to assess a woman’s progress in labour. It requires the examiner to wear sterile gloves and insert two lubricated fingers into the vagina to examine the woman’s cervix. This process can be uncomfortable for women, especially during the early stage of labour when the professional may reach quite high for the cervix to do the assessment. The health care provider may ask the woman to elevate her hips on a blanket to make the process easier. During the examination, it can be helpful for a woman to focus on relaxing, to breathe slowly and deeply, and to follow the instructions of her health care provider. The exam should only be done when medically necessary to avoid infection and any undue discomfort for the woman.10,31
When health care providers perform vaginal examinations during labour, they can also determine where the presenting part of the fetus (usually its head) is in comparison to the mother’s ischial spines. This is called determining the station of the fetus. The station is a measurement used to assess the descent of the baby into the birth canal in preparation for birth. If the presenting part is found to be at the level of the woman’s ischial spines, the station of the fetus is said to be at 0 (zero). If the presenting part is 1 cm above the woman’s ischial spines, the station would be designated as -1. If the presenting part is 1 cm below the ischial spines, the station would be designated as +1. Birth is imminent at a station of +4 to +5.10
During the first stage of labour, a woman’s cervix undergoes 100 percent effacement and dilates from 0 cm to 10 cm. This occurs as a result of increasingly intense contractions, which become closer together and last longer.3,10
The first stage of labour can be further subdivided into three different phases. Different physiological events occur in each of these phases requiring the use of different coping skills. The three phases are as follows:
- Early labour.
- Active labour.
- Transition phase.3,10
During early labour, the cervix of a primigravida dilates from 0 cm to 3 cm and for a multiparous woman dilates from 0 cm to 4 cm or 5 cm.32 The American College of Obstetricians and Gynecologists (ACOG) have recently made new recommendations that may impact the definition of early labour. They state: “Cervical dilation of 6 cm should be considered the threshold for the active phase of most women in labor. Thus, before 6 cm of dilation is achieved, standards of active phase progress should not be applied”. This recommendation is one of several recommendations for the safe prevention of primary caesarean births.33 Regardless of the definition of early labour, the cervix of primigravidas will completely efface during this phase, and the cervix of multiparous women will continue to efface throughout the first stage of labour. For primigravidas, the station of the presenting part of the fetus will reach 0; for multiparous women, the station of the presenting part will reach a station of 0 to +2. During this phase, uterine contractions will be mild to moderate in intensity, occurring every 5 â 30 minutes, and will last about 30 â 45 seconds. These changes are average and may differ for individual women. Women will likely still be able to talk during these contractions.10
During the early phase of labour, a woman who presents herself at her birth setting may be asked to go home and come back to the birth setting once her labour has further progressed.Â This would only be suggested if she has had a low risk pregnancy, her amniotic fluid is clear (if her amniotic membrane has ruptured), and she presents with no maternal or fetal concerns. Alternatively, she may be able to wait in a designated area of the hospital for women in early labour. The aim of most labour-assessment programs is to delay the admission of women until they are in active labour. This is helpful to prevent unnecessary interventions during the early labour phase for women and to allow women to be relaxed and comfortable in their own envrionment.2,3,5,20,34 Some women or their support person(s) can experience difficulty leaving the care setting due to a combination of uncertainty, pain, and anxiety. They should be reassured, provided with an explanation of why it is recommended to leave the birth setting during this stage of labour, and given information about when to call or come back in.35 People should also be provided with information on coping mechanisms that they can use during this time (e.g., distraction activities, ambulation, and rest).10,35 See the file on Labour Support for more information on coping strategies during labour.
The SOGC describes the start of active labour as the presence of a pattern of contractions leading to cervical effacement and dilation after 3 cm to 4 cm in a primigravida or 4 cm to 5 cm in a multiparous woman.32 During active labour, a woman’s cervix will continue to dilate to 8 cm; the station of the presenting part of the fetus will reach +1 to +2; and her uterine contractions will become moderate to strong in intensity, occurring every three to five minutes and lasting about 40 â 70 seconds.7,10
This is the stage when most women are admitted to their birth setting unless they are planning a home birth. A woman and her fetus tend to be monitored closely during this phase to ensure their well-being. A woman’s contractions also intensify during this phase and she tends to rely heavily on her support system to help her cope with the pain.3,7,10 Please see the files on Labour Support and Pain Management for information on coping strategies during labour.
During the transition phase of labour, a woman’s cervix will dilate from 8 cm to 10 cm; the station of the presenting part of the fetus will reach +2 to +3; and her uterine contractions will become strong to very strong, occurring every two to three minutes and lasting about 45 â 90 seconds.10
As a woman’s contractions can be the strongest yet during this phase of labour, women may have difficulty coping with the pain and may even want to give up. During this time, it is important to provide ample praise and encouragement, and to encourage women to stay focused.3,10
The second stage of labour is defined as the period from full cervical dilation (10 cm) to the birth of the baby.3,10 The second stage of labour can be the most strenuous and energy depleting part of labour, especially for first-time mothers, as this is when pushing occurs.3,10,36
Second stage â passive (full cervical dilation without pushing)
During this stage, a woman is fully dilated, but she does not yet begin pushing if she does not have the urge to. Her contractions and the fetal heart rate continue to be monitored, and her uterine contractions work to help to move the baby further down into the birth canal. This stage is often considered a time for a woman to rest and regain her energy as both she and her baby prepare for the process of birth.10,36
Second stage â active (full cervical dilation with pushing)
During this stage, women will feel the natural, spontaneous urge to push and will then push with contractions. If a woman has an epidural and does not feel this urge or feel it as strongly, a health care provider can instruct her when to push.10,38
Women should push in whichever position feels most comfortable for them. If progress is slow, gravity and a change in position can often assist with fetal descent and labour progress. Some positions to try when pushing could include the following:10,38
- Semi-Fowler in bed (with or without legs in stirrups).
- Sitting on a commode chair, toilet, or a birthing stool.
- Lateral or side-lying.
A woman and her health care provider should discuss positions that she may like to try during labour. See the Labour Support file for more information on the benefits of trying different positions during labour.
The vaginal birth process
The vaginal birth process is usually a fairly quick process; however, there are still many key events, which need to occur during this time. A woman can feel quite anxious during this time and feel a sense of burning as the baby is crowning (becomes visible and stretches the vaginal and perineum tissue). It is important for her to remain focused and remain able to listen to guidance given by her health care provider(s).10,39
The head of the baby is typically the first part to be born. See the file on Breech Birth for information on a birth process where body parts other than the head are to be born first. As a woman’s pelvis has many different contours, the fetus’s head must adapt to the birth canal for vaginal birth to occur. For birth to occur, a fetus undergoes the following seven cardinal movements:10
- Engagement of the fetus into the birth canal.
- Descent of the fetus down into the birth canal.
- Flexion of the fetus’ head once the fetus’ head meets resistance from the birth canal.
- Internal rotation of the fetus’ head so it is in the occiput anterior position (face down).
- Extension of the fetus’ head once it reaches the perineum.
- External rotation of the fetus’ head (to face the inside of the mother’s thigh) after the head is born so that it realigns with its body.
- Expulsion or birth with the anterior shoulder being born before the posterior shoulder.
After the head emerges, most health care providers check for a nuchal cord, which occurs when the umbilical cord is wrapped around the baby’s neck. When this occurs, subsequent management depends upon how tight it is. A loose nuchal cord is usually pulled and looped back over the baby’s head. When the cord is too tight for this manoeuvre, the baby may be delivered by a somersault manoeuvre or the cord may be clamped, cut, and unwound before the birth of the baby’s body. Some women have been expressed not wanting a vaginal exam done during the birth process to check for a nuchal cord, but it be helpful to know that the procedure of checking for a nuchal cord can be beneficial for the baby.40,41
As soon after birth as possible, the newborn is placed in physical contact with the mother (skin-to-skin) to promote bonding and establish breastfeeding.3 See the files on Newborn Care and Breastfeeding for more information on this topic.
During the third stage of labour, the placenta normally separates from the uterine wall and is then delivered. A woman typically feels a few mild contractions when this is about to occur, prompting her to push out the placenta.3,10 The health care provider can either hold the cord and gently pull down on it in anticipation for the birth of the placenta (called active management) or allow the placenta to detach without controlled traction (physiological management). More information on active versus physiological third-stage management can be found in the Resources and Links section.
The time from the birth of the baby to the birth of the placenta is normally not long. Research has shown that 50 percent of placentas are delivered within five minutes of the birth of the baby, and 90 percent of placentas are delivered within 15 minutes of the birth of the baby.42,43 If a placenta takes longer than 30 minutes to be delivered, this puts a woman at significant risk of losing an excessive amount of blood, referred to as postpartum hemorrhage (PPH).43,44 PPH is a major risk factor for maternal mortality with the most number of deaths occurring in the first four hours following birth, thus prevention and close monitoring for PPH are important.44
Oxytocin, a hormone naturally present in a woman’s body, causes the uterus to contract throughout labour; it also plays a role in preventing PPH. Following the birth of the baby, contractions continue as a result of the buildup of oxytocin, which acts to help a woman deliver her placenta as well to sustain her uterus in a contracted state to prevent excessive bleeding.10 The SOGC recommends that all women receive a supplemental, synthetic form of oxytocin to further prevent PPH. It is usually given after the birth of the anterior shoulder of the baby, via an injection into a woman’s arm or leg muscle or intravenously.44
If a woman happens to lose a larger than normal amount of blood during the process of birth, her health care providers can administer medications to help the uterus clamp down and prevent further bleeding. Volume expanders and/or a blood transfusion may also be administered if the hemorrhage is severe.10
Clamping and cutting the umbilical cord
After a baby is born, he or she is still attached to the undelivered placenta via the umbilical cord. A support person is often invited by the health care provider to ‘cut the cord’ at this time. The health care provider will first clamp the cord in two places, and then a cut will be made between the two clamps. The baby or the mother does not feel any pain when the cut is made as there are no nerves present in the umbilical cord.10
Delayed cord clamping is becoming a common practice. This involves waiting anywhere from one to three minutes to the complete end of the pulsation of the cord before it is clamped and cut. Research has shown that waiting to clamp the cord instead of doing it immediately upon birth can result in increased blood transfusion to the newborn thereby leading to an increased supply of iron and a decreased risk of the newborn developing anemia.45 If parents want to have delayed cord clamping done, they should speak to their health care provider before the birth to discuss its proposed benefits and their wishes at the time of birth.
Umbilical cord blood
While waiting for the placenta to detach from the uterine wall and be delivered, most health care providers collect blood samples from the umbilical cord. The umbilical cord of a baby typically has one large vein and two small arteries. One blood sample will be taken from the vein, and one blood sample will be taken from an artery. The cord blood samples will then be sent to the laboratory and tested for blood gases, the baby’s blood type, and other tests as required.10
An increasing number of people are requesting that blood be collected from the umbilical cord at birth to be stored for possible future uses. The rich supply of stem cells found in cord blood can be used to treat certain cancers and other conditions. The process of collecting cord blood at birth and storing it is known as umbilical cord blood banking.46 This is not a service routinely provided at birth, but expectant parents may request it if they have made arrangements prior to their baby’s birth. It is important that families know that most cord blood banks in Canada are private organizations thus parents must pay for this service out-of-pocket and that the services can be expensive. Some companies also collect blood for public backing at no charge to parents. Choosing whether to bank a baby’s cord blood and which company to use for cord blood banking is the responsibility of the expectant parent(s). Parents should discuss the impact of delayed cord clamping on the available volume of blood for cord blood banking with their chosen cord blood bank. More information about cord blood banking can be found in the Resources and Links section.
Referrals may be warranted if a woman or her support person(s) are:
- Overly anxious or fearful about the process of labour and birth.
- Require more information about labour and birth in general.
Women and/or their support person(s) who require more information and/or support leading up to labour and birth can be referred to the following sources:
- Their health care provider (obstetrician, family physician, Nurse Practitioner, or midwife).
- Prenatal education classes, if not already enrolled.
- Their local public health unit.
- A doula, or other support person, with a special interest in helping women build confidence in being able to give birth.
Resources & Links
- Society of Obstetricians and Gynaecologists of Canada (SOGC)
- Clinical Practice Guideline: Active management of the third stage of labour: prevention and treatment of postpartum hemorrhage (2009)
- Policy Statement: Joint Policy Statement on Normal Childbirth (2008)
- Clinical Practice Guideline: Umbilical Cord Blood: Counselling, Collection, and Banking (2015)
- Position Paper: Rural Maternity Care (2012)
- The American Congress of Obstetricians and Gynecologists (ACOG)
- Association of Ontario Midwives (AOM)
- Canadian Association of Midwives (CAM)
- Canadian Association of Perinatal and Women’s Health Nurses (CAPWHN)
- Society of Obstetricians and Gynaecologists of Canada (SOGC)
- Buckley, S. J. (2015). Hormonal physiology of childbearing: Evidence and implications for women, babies, and maternity care. Washington, DC: Childbirth Connection Programs, National Partnership for Women and Families. Retrieved from http://transform.childbirthconnection.org/reports/physiology/
- Lavender, T., Hart, A., & Smyth, R. M. D. (2013). Effect of partogram use on outcomes for women in spontaneous labour at term. Cochrane Database of Systematic Reviews, 7(CD005461), 1-28. doi: 10.1002/14651858.CD005461.pub4.
- Osborne, K., & Hanson, L. (2014). Labor down or bear down: A strategy to translate second-stage labor evidence to perinatal practice. The Journal of Perinatal & Neonatal Nursing, 28(2), 117-126. doi: 10.1097/JPN.0000000000000023
- Public Health Agency of Canada (2012)
- Canadian Blood Services
- HealthyFamilies BC
- Ontario Ministry of Health and Long-Term Care
Prenatal Education Provider Tools
- Best Start Resource Centre (BSRC)
- Perinatal Services BC
Client Resources and Handouts
- Best Start Resource Centre (BSRC)
- Injoy Health Education
- The Miracle of Birth 4: Five Birth Stories, 2014.
- Stages of LabourÂ 3rd Edition: A Visual Guide, 2013
- Understanding Birth 3rdÂ Edition: A Comprehensive Guide, 2015
- Schuurmans, N., Senikas, V., & Lalonde, A. (2009). Healthy Beginnings: Giving your baby the best start from preconception to birth (4th ed.). Etobicoke, ON: John Wiley and Sons Canada Ltd.
Labour decision tree for labour at term
Click decision tree for larger PDF version.
- Buckley, S. J. (2015). Hormonal physiology of childbearing: Evidence and implications for women, babies, and maternity care. Washington, DC: Childbirth Connection Programs, National Partnership for Women and Families. Retrieved from http://www.childbirthconnection.org/resources/resources-q-a/advocates-and-professionals.html
- Society of Obstetricians and Gynaecologists of Canada. (2008). Joint policy statement on normal childbirth. Journal of Obstetrics and Gynaecology Canada, 30(12), 1163-1165. Retrieved from http://www.jogc.com/
- Health Canada. (2000). Chapter 5: Care during labour and birth. Family-centred maternity and newborn care: National guidelines (pp.5-49). Ottawa, ON: Author.
- El-Hamamy, E., & Arulkumaran, S. (2005). Poor progress of labour. Current Obstetrics & Gynaecology, 15(1), 1-8. Retrieved from http://www.obstetrics-gynaecology-journal.com/article/S0957-5847%2801%2990225-2/abstract
- Gharoro, E. P., & Enabudoso, E. J. (2006). Labour management: An appraisal of the role of false labour and latent phase on the delivery mode. Journal of Obstetrics & Gynecology, 26(6), 534-537. doi: 10.1080/01443610600811094
- Lynch, C. D., & Zhang, J. (2007). The research implications of the selection of a gestational age estimation method. Paediatric and Perinatal Epidemiology, 21(2), 86-96. doi: 10.1111/j.1365-3016.2007.00865.x
- Albers, L. L. (2007). The evidence for physiologic management of the active phase of the first stage of labor. Journal of Midwifery & Womenâs Health, 52(3), 207-215. doi: 10.1016/j.jmwh.2006.12.009
- Public Health Agency of Canada. (2009). What mothers say: The Canadian maternity experiences survey. Ottawa, ON: Author. Retrieved from http://www.phac-aspc.gc.ca/rhs-ssg/survey-eng.php
- Better Outcomes Registry and Network (BORN) Ontario. (2012). Perinatal health indicators for Ontario. Ottawa, ON: Author. Retrieved from https://www.bornontario.ca/assets/documents/specialreports/Perinatal%20Health%20Indicators%20for%20Ontario%202012.pdf
- Perry, S. E., Hockenberry, M. J., Lowdermilk, D. L., & Wilson, D. (2013). Unit 4: Childbirth. In C. Sams & L. Keenan-Lindsay (Eds.), Maternal child nursing care in Canada (pp. 378-488). Toronto, ON: Elsevier Canada.
- World Health Organization. (1996). Care in normal birth: A practical guide. Geneva, CH: Author. Retrieved from http://www.who.int/maternal_child_adolescent/documents/who_frh_msm_9624/en/
- Adams, S. S., EberhardâGran, M., & Eskild, A. (2012). Fear of childbirth and duration of labour: A study of 2206 women with intended vaginal delivery. BJOG: An International Journal of Obstetrics & Gynaecology, 119(10), 1238-1246. doi: 10.1111/j.1471-0528.2012.03433.x
- Sheiner, E., Levy, A., Katz, M., & Mazor, M. (2005). Short stature – an independent risk factor for Cesarean delivery. European Journal of Obstetrics & Gynecology and Reproductive Biology, 120(2), 175-178. doi:10.1016/j.ejogrb.2004.09.013
- Gibbins, J., & Thomson, A. M. (2001). Women’s expectations and experiences of childbirth. Midwifery, 17(4), 302-313. doi: 10.1054/midw.2001.0263
- Ferguson, S., Davis, D., & Browne, J. (2013). Does antenatal education affect labour and birth? A structured review of the literature. Women and Birth, 26(1), e5-e8. http://dx.doi.org/10.1016/j.wombi.2012.09.003
- Murphy, D. J., Pope, C., Frost, J., & Liebling, R. E. (2003). Women’s views on the impact of operative delivery in the second stage of labour: Qualitative interview study. British Medical Journal, 327(7424), 1132-11136. http://dx.doi.org/10.1136/bmj.327.7424.1132
- Escott, D., Slade, P., & Spiby, H. (2009). Preparation for pain management during childbirth: The psychological aspects of coping strategy development in antenatal education. Clinical Psychology Review, 29(7), 617-622. doi: 10.1016/j.cpr.2009.07.002
- Fair, C. D., & Morrison, T. E. (2012). The relationship between prenatal control, expectations, experienced control, and birth satisfaction among primiparous women. Midwifery, 28(1), 39-44. doi:10.1016/j.midw.2010.10.013
- Nolan, M. L. (2009). Information giving and education in pregnancy: A review of qualitative studies. The Journal of Perinatal Education, 18(4), 21-30. doi: 0.1624/105812409X474681
- Ragusa, A., Mansur, M., Zanini, A., Musicco, M., Maccario, L., & Borsellino, G. (2005). Diagnosis of labor: A prospective study. Medscape General Medicine, 7(3), 61.
- Becher, N., Waldorf, K. A., Hein, M., & Uldbjerg, N. (2009). The cervical mucus plug: structured review of the literature. Acta obstetricia et gynecologica Scandinavica, 88(5), 502-513. doi: 10.1080/00016340902852898
- MacKinnon, K., & McIntyre, M. (2006). From Braxton Hicks to preterm labour: The constitution of risk in pregnancy. Canadian Journal of Nursing Research), 38(2), 56-72. Retrieved from http://www.mcgill.ca/cjnr/home
- Gross, M. M., Hecker, H., Matterne, A., Guenter, H. H., & Keirse, M. J. (2006). Does the way that women experience the onset of labour influence the duration of labour?. BJOG: An International Journal of Obstetrics & Gynaecology, 113(3), 289-294. doi: 10.1111/j.1471-0528.2006.00817.x
- Tita, A. T., & Andrews, W. W. (2010). Diagnosis and management of clinical chorioamnionitis. Clinics in Perinatology, 37(2), 339-354. doi:10.1016/j.clp.2010.02.003
- Reilly, D. R., & Oppenheimer, L. W. (2005). Fever in term labour. Journal of Obstetrics and Gynaecology Canada, 27(3), 218. Retrieved from http://www.jogc.com/
- Khazardoost, S., Hantoushzadeh, S., Khooshideh, M., & Borna, S. (2007). Risk factors for meconium aspiration in meconium stained amniotic fluid. Journal of Obstetrics & Gynecology, 27(6), 577-579. doi:10.1080/01443610701469636
- Dargaville, P. A., & Copnell, B. (2006). The epidemiology of meconium aspiration syndrome: Incidence, risk factors, therapies, and outcome. Pediatrics, 117(5), 1712-1721. doi: 10.1542/peds.2005-2215
- Lee, K. A., Mi lee, S., Jin Yang, H., Park, C. W., Mazaki-Tovi, S., Hyun Yoon, B., & Romero, R. (2011). The frequency of meconium-stained amniotic fluid increases as a function of the duration of labor. Journal of Maternal-Fetal and Neonatal Medicine, 24(7), 880-885. doi:10.3109/14767058.2010.531329
- Money, D. M., & Dobson, S. (2004). The prevention of early-onset neonatal group B streptococcal disease. Journal of Obstetrics and Gynaecology Canada, 26(9), 826-840. Retrieved from http://www.jogc.com/
- Lin, F. Y. C., Weisman, L. E., Azimi, P., Young, A. E., Chang, K., Cielo, M., . . . Robbins, J. B. (2011). Assessment of intrapartum antibiotic prophylaxis for the prevention of early-onset group B Streptococcal disease. The Pediatric Infectious Disease Journal, 30(9), 759-763. doi: 10.1097/INF.0b013e31821dc76f
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