The stages of labour

Braxton Hicks contractions

Braxton Hicks contractions, often called "false contractions", result from the tightening and relaxing of the muscular fibres of the uterus. Present from the 1st trimester of pregnancy, they are generally felt from the 2nd or 3rd trimester onwards (1). These spasmodic contractions occur following a period of intense activity, when the bladder is full, after sexual activity or in cases of dehydration. Although they prepare the body for labour, they do not indicate that labour has begun. They are a normal stage of pregnancy (2) and indicate signs a few days before labour. 

They are irregular in duration and intensity, unpredictable, non-rhythmic and do not cause cervical dilation. They ease and then disappear, only to reappear (1).

It is important to monitor these contractions to detect any significant change or unusual symptom that could indicate the onset of labour requiring medical attention.

Loss of the mucus plug

Cervical mucus is produced by the glands of the cervix (3). From the 4th week of pregnancy, cervical mucus thickens and accumulates at the level of the cervix to gradually form a hermetic seal — this is the "mucus plug". This structure of the cervical canal thickens throughout pregnancy to protect the foetus by preventing the passage of bacteria and external agents at the level of the vagina (5). 

Loss of the mucus plug does not necessarily mean that labour has begun! Other signs of labour must accompany it, such as regular contractions and rupture of the amniotic sac. The mucus plug can come away at any point in the weeks preceding the onset of labour, but it may also only come away once labour has begun. 

Rupture of the amniotic sac

The amniotic sac is the membrane in which the foetus develops, surrounded by amniotic fluid (6). 

Membrane rupture can occur at any point during pregnancy and often precedes the onset of uterine contractions. Under physiological conditions, the membranes rupture spontaneously during labour at full dilation. The amniotic sac breaks and amniotic fluid flows through the vagina — this is known as the waters breaking. Sometimes the rupture occurs early, during labour before the cervix is fully dilated. 

Rupture of the amniotic sac may be sudden, with a heavy flow of amniotic fluid, or it may be more discreet — referred to as a leak. In both cases, it generally indicates the onset of labour and the imminence of birth. This situation should prompt the expectant mother to contact her maternity unit, as the absence of amniotic fluid in the amniotic sac increases the risk of infection for both mother and baby. 

In the event of insufficient progress in labour, the midwife or doctor may consider an artificial rupture of the amniotic sac (amniotomy) to accelerate the baby's descent. However, this practice is controversial and must be carried out with caution. The WHO classifies it as a "practice for which insufficient evidence exists to support a clear recommendation and which should be used with caution while research continues" (8).

Membrane sweeping 

The membrane sweeping is a procedure carried out during a pelvic examination in which the practitioner uses their fingers to separate the amniotic sac from the uterine wall. This action can release prostaglandins that help soften the cervix to prepare it for labour and trigger contractions (9). 

Studies on the effectiveness of membrane sweeping in inducing labour are unreliable (10), with some showing that it promotes the onset of labour, and others not (11, 12). Research suggests that cervical massage could be an effective alternative to help with cervical ripening (13).

There are risks of infection, pain and bleeding (14-17). 

Vaginal examination 

The vaginal examination is a physical examination of a woman's pelvic organs frequently carried out before labour to assess the position and condition of the cervix, the bony pelvis and foetal presentation (18). 

Although this practice is not systematically recommended by the WHO, vaginal examination is offered when the woman is in early labour (latent phase) to monitor the progress of labour or to artificially induce labour through membrane sweeping (19). 

An alternative to vaginal examination is observation of the "purple line". This red/purple line appears between the buttocks (from the anal margin to the top of the buttocks) at the beginning of the 2nd stage of labour and is thought to correlate with cervical dilation and the position of the foetal head (20). Studies have shown that this line is present in approximately 76% of women in labour (21), and its length appears to be an indicator of cervical dilation and the position of the foetal head (22). 

Evening primrose oil 

Evening primrose oil is a rich source of essential omega-6 fatty acids, including gamma-linolenic acid. This pregnancy supplement is thought to act as a precursor to prostaglandins E1 and E2, which contribute to cervical ripening and may thus help to promote a natural birth (26).

However, the data on the effectiveness of evening primrose oil in inducing or accelerating labour are conflicting (27). Some studies have shown that taking evening primrose oil orally had no significant effect on inducing or accelerating labour (28), while one study showed that it could reduce cervical length and improve the Bishop score (a clinical score of cervical status) without necessarily inducing labour (29).

Taking evening primrose oil orally is not without risks. Its consumption has been associated with an increased incidence of prolonged rupture of membranes, increased oxytocin, arrested descent of the baby and vacuum extraction (30).

Trials have also examined the use of evening primrose oil vaginally on cervical ripening and have shown promising results, including an improvement in the Bishop score and a shorter duration of labour (31, 32).

To find out more, read our article: evening primrose oil labour.

Induction of labour

Whether voluntary or medically indicated, in 2016 in France, 22% of births were induced. Several situations require a induction of labour, this is notably the case in the following situations: post-term pregnancy, premature rupture of membranes, multiple pregnancy, or certain specific circumstances such as foetal macrosomia, intrauterine growth restriction, a history of rapid labour, or pre-eclampsia.

Various methods, with varying degrees of demonstrated effectiveness, may be used to induce labour: 

• Membrane sweeping
• Oxytocin injection
• Prostaglandin injection

When comparing different methods of labour induction, prostaglandins proved more effective than oxytocin, which was more likely to result in an unfavourable or unchanged cervix between 12 and 24 hours. Likewise, prostaglandins were associated with less recourse to epidural analgesia (44). 

Certain natural methods may also help to induce labour. For example, emptying the bladder to allow the baby's head to press against the cervix, or encouraging movement to mobilise the pelvis and help the baby engage. Acupuncture, specific massages, and pain and stress management are other techniques that may be used to soften the cervix and encourage dilation. To find out more, see our article on acupuncture pregnancy.

The dilation phase

Labour begins when uterine contractions are accompanied by cervical changes. Characterised by 3 distinct phases, the dilation phase is the first stage of labour. It begins with the first regular contractions and ends when the cervix is fully dilated (45).

• The latent phase: The cervix begins to efface (thin) and dilate (widen) to 3–4 cm, with irregular and moderately painful contractions every 5 to 25 minutes lasting 30 to 45 seconds. This phase, usually the longest, often takes place at home.
• The active labour phase: The cervix continues to efface and dilates on average by ½ centimetre per hour to 7–8 cm. Contractions become longer, closer together, and more painful, occurring every 5 minutes at most and lasting approximately 60 seconds. Waters breaking is common during this phase.
• The transition phase: The cervix reaches maximum opening, at 10 cm. This is the shortest phase, but the most difficult, as contractions are longer and closer together, occurring every 6 minutes at most and lasting 60 to 90 seconds.

At the end of the dilation phase, the baby's head engages in the pelvic outlet, which is particularly narrow. It is common at this point to feel strong pressure as well as nausea, or even vomiting. The duration of the dilation phase is influenced by several factors, including the number of previous pregnancies, the ability to move around, the baby's weight and position, the shape of the pelvis, and the mother's psychological state and birth preparation.

The expulsion phase

The second stage of labour corresponds to the active expulsion phase, characterised by full dilation of the cervix (45). Uterine contractions become intensely strong, rhythmic, and frequent, encouraging the descent of the foetus into the maternal pelvis. Expulsion is supported by pushing directed by the midwife and stimulated by the mother-to-be in response to contractions. 

When birth becomes imminent, the baby's head becomes visible at the vaginal opening.

A controlled incision of the perineum under local anaesthesia (episiotomy) may be decided upon by the midwife or obstetrician to widen the vaginal opening and prevent tearing of the perineum. At the same time, the baby's head appears, the neck stretches, and the rest of the body is delivered. The duration of this phase varies, influenced by physiological factors such as foetal position, the effectiveness of uterine contractions, and the mother's response to pushing efforts. 

Delivery of the placenta

The third stage of labour involves the natural or assisted expulsion of the placenta and its membranes (placental membranes and umbilical cord), more commonly known as delivery of the placenta (45). Some time after the birth of the baby, the placenta detaches and is expelled in turn. To do so, the uterus contracts. As the placenta separates from the uterine wall, the wall may begin to bleed. The placenta is then examined to ensure it has come out in its entirety, as any remaining tissue can cause infection and subsequent bleeding in the uterus.

The cord is then cut. Delayed cord clamping involves waiting more than one minute, or until the cord stops pulsating, before cutting it. Delayed clamping has significant health benefits for the newborn, such as increased blood volume, iron stores, and a reduction in the risk of complications.  

Some mothers may choose to keep the placenta, to make a tincture, or even to consume it, although the benefits have not been demonstrated. 

Eating and drinking during labour

Official recommendations on eating and drinking during labour vary between medical organisations. 

• The French Society of Anaesthesia and Intensive Care permits non-particulate fluids for women receiving epidural analgesia, except in cases of diabetes, morbid obesity, or caesarean section (67).
• The American Society of Anesthesiologists permits a modest intake of clear fluids for patients in uncomplicated labour, whilst advising against solid foods (68).
• The Haute Autorité de Santé permits clear fluids throughout labour for patients at low risk of general anaesthesia, but advises against solid foods during the active phase of labour (69).

Fasting during labour helps to prevent Mendelson's syndrome in the mother-to-be, a rare risk of aspiration pneumonitis (bronchial inhalation of gastric contents) in the event of general anaesthesia (5). However, with the decline in the use of general anaesthesia for caesarean sections, this risk has become very low, as the mother-to-be is now awake and her cough reflex more intact (70). 

Therefore, if labour is low-risk and general anaesthesia is unlikely, it is generally possible to eat and drink during labour. Studies show that eating and drinking does not increase maternal or neonatal complications (71) and may even slightly reduce (~16 min) the duration of labour (72). 

In some cases, you will be on a drip during labour to maintain hydration. To find out more, see our article on the subject. 

Passing stools during labour

Although it does not happen at every birth, it is very common to have a bowel movement during the expulsion phase. The baby exerts pressure on the rectal ampulla, a part of the rectum situated just before the anus, which often contains stools that are then pushed towards the anus. It is a mechanical process, and just as frequent as it is normal! 

The postpartum recovery and those first moments with your baby are an intense and delicate period of transition, during which the support and care given to the mother can greatly influence her wellbeing and that of her baby. The days following birth require a period of adjustment. Your body needs to recover from the many physical and hormonal changes brought on by pregnancy and childbirth. To support a good recovery, you can turn to the best postpartum dietary supplement: collagen! It supports muscle recovery, and helps maintain tissues and the body.

During this period, rest is crucial to allow for physical recovery and adjustment to the presence of a newborn. Hormonal changes can bring about feelings of doubt or sadness, commonly known as the "baby blues". This state, which is common in the days following birth, can include symptoms similar to those of postpartum depression such as sleep disturbances, intense fatigue or low self-esteem. This temporary period, generally lasting less than two weeks, should not be a source of guilt.

Physically, the uterus begins to return to its normal size, a process that may be accompanied by pains known as afterpains. You may also experience perineal pain, especially if you had an episiotomy or tearing. Postpartum bleeding, known as lochia, is also normal and can last several weeks. This is distinct from the return of periods, which refers to the first period after childbirth. 

Those first moments with your baby are essential for building a strong emotional bond. Skin-to-skin contact is particularly beneficial. It not only encourages attachment, but also helps regulate your baby's body temperature. Give yourself time to adjust to your role as a mother and to get used to this new chapter in your life. Don't hesitate to share your concerns and worries with your partner, your loved ones, or a healthcare professional.

Every birth is ultimately a unique and unforgettable experience. Preparing both physically and mentally for labour is crucial for approaching this moment with less apprehension and greater confidence.  

Postpartum recovery is unique to each mother. Listening to your body's needs and limits while surrounding yourself with support is essential to the healing process.