Progression of labour

Onset of labour

The root cause of onset of labour is unknown. Uterus contracts painlessly throughout pregnancy, but the contractions begin to increase during the last weeks and the cervix matures. Labour is often preceded by transient uterine contractions that last for a few hours, and it does not always indicate the onset of labour.

The cervical channel has a cervical mucus plug, i.e. operculum, that protects the baby from inflammations. This plug, which may also contain blood, usually detaches from the cervix 1 to 7 days before the actual onset of labour.  Labour often begins with irregular contractions that gradually become more regular, frequent, and intense. During the contraction, the uterus feels hard and the contraction feels painful. During the contractions, the cervix shortens and dilates. This stage may include blood-tinged mucous bleeding.

Labour can also begin with the breaking of water, i.e. amniotic fluid, when the fetal membranes burst. After the breaking of the water, contractions begin gradually within a few hours. If this is not the case, the onset of labour can be induced with an intravenous oxytocin drip, a vaginal insertion drug or by mechanically dilating the cervix with a catheter.

Dilation stage

The dilation stage begins when regular uterine contractions that dilate the cervix begin. The stage ends when the cervix has completely dilated to 10 cm. During the dilation stage, the cervix softens and disappears, and the presenting part of the baby – head or bum – descends to the pelvic floor of the mother. This stage may take several hours, but large variations are also possible. The dilation stage lasts for approximately 7 to 14 hours in primiparae labours, and 6 to 10 hours in multiparae labours.

At the beginning of the dilation stage, contractions are infrequent and of short duration. At this point, contractions can manifest as pain in the lumbar region. If the mother feels she is coping with the contractions, she may well still stay at home. You can always call the maternity hospital or your own clinic to ask if you should go to the hospital.  During the dilation stage, you can eat and drink normally and move around according to your sensations. It is important to stay relaxed. This allows the contractions to dilate the cervix and the labour progresses. As the dilation stage progresses, the contractions change. During the dilation of the last few centimetres, the contractions come every 5 to 6 minutes and last for approximately one minute.

During the labour, the midwife monitors the mother’s blood pressure, pulse and body temperature. The baby’s well-being is monitored by observing their heart rate and the frequency and duration of contractions. Internal examinations are performed during the dilation stage to monitor the progression of the dilation and labour. If the amniotic fluid has not broken, the fetal membranes may be punctured during the dilation stage to progress the labour or to monitor the baby’s well-being more closely. Occasionally, contractions can be induced during the dilation stage with an intravenous oxytocin drip.

Transition stage

Transition stage is a stage between the dilation stage and the pushing stage.

At this point, the cervix is completely dilated and the mother experiences a sense of weight that resembles the need to go to the toilet, but she does not yet have a clear need to push. If the mother’s and baby’s well-being allow, the need for the mother to push can be awaited calmly. During the transition stage, the baby descends in the birth canal and turns the head to a position favourable for labour. During the transition, the upright position of the deliverer helps the baby descend in the birth canal.
Identifying the transition stage is important so that pushing is not initiated too early. Pushing too early may cause fatigue in the mother, prolong the pushing stage, and possibly increase distress of the baby and deteriorate well-being.

Pushing stage

The need for pushing arises as the baby descends in the birth canal. The baby is born as the mother pushes during a contraction, while the midwife supports the perineum. This support is important in order to prevent tears. If necessary, the midwife may apply local anaesthesia on the perineum and occasionally, to expedite the birth of the baby, cut the perineum. The pushing stage lasts from a short few minutes to a maximum of a couple of hours. The delivery is sometimes expedited by a suction cup.

In Finland, most give birth in a semi-sitting position. Alternative pushing positions include standing up, on all fours, on one’s side, or sitting on a birthing chair. Usually the mother is the best judge of the best pushing position, and the positions can be varied as needed.

Afterbirth

Afterbirth stage is a stage in which the baby is already born, but the afterbirths, i.e. the placenta, membranes and umbilical cord, are still in the uterus. The baby is set by the mother immediately after birth. The mother may be given a drug that contracts the uterus. When the baby is born, the uterus usually contracts quickly and the placenta detaches by the contractions. A little push by the mother causes the placenta to be born, usually approximately 20 to 30 minutes after labour. The father or the support person may cut the umbilical cord if they wish. The baby will be assisted in breastfeeding for the first time. Baby on the breast enhances placenta delivery. Any tears are also sewn in the afterbirth stage. Occasionally, removal of the placenta is accelerated by pressing on the mother’s uterus and simultaneously pulling by the umbilical cord. Occasionally, the placenta has to be removed by hand in the operating room, and a uterine curettage is performed at the same time.

After the baby is born and calmed down, it is time for the baby to be bathed and measured. The well-being of the mother and the baby is observed in the delivery room for a few hours. After that, the family is transferred to the postnatal ward to recover and practice a new life together.

Author: Matleena Aitasalo, Health Nurse, Breastfeeding Advisor, previously worked for the Family Federation of Finland.

References:
Kanta-Häme Hospital District Maternity training at Kanta-Häme Hospital District. 
Finnish Institute for Health and Welfare We’re are having a baby Guide for expecting and caring for a baby.
Tiitinen, Aila Normal labour (Normaali synnytys) Duodecim Health Library.