Dilation is the early stage of labour in which the cervix slowly opens to allow the head of the baby to descend. The foetus must progress through the birth canal and adapt the characteristics of the head to the size of the pelvis. During this stage the type of contractions and the heart’s reaction should be monitored in order to detect any abnormalities that might indicate foetal distress.
The duration of this stage varies, depending on whether the patient is nulliparous (first birth) or multiparous (multiple births) and the foetal and maternal characteristics. Traditionally, nulliparous (first birth) women tend to complete dilation in 12 -14 hours and women who have already been through childbirth usually take 8 hours. Dilation is measured in cm and start out slow but speed up at 5 cm dilation. A woman is considered fully dilated at 10 cm, when the mother is 10 cm dilated; now the head has to move down the vagina and the baby adapt to the pelvis in order to be born.
This is the most exciting stage. It starts at full dilation and ends when the baby is born and usually lasts an hour for a first delivery and 30 minutes for subsequent births. Contractions increase in intensity and pain, although in many cases an epidural has already been administered.
In many cases, particularly in first-time mothers, an episiotomy is required when the baby’s head begins to crown. This is an incision made in the posterior vaginal wall to prevent vaginal tears in places that could be harmful to the mother’s rectal sphincter or bladder.
In some cases instruments are required to help with delivery. There are three instrument that can be used in childbirth and which we only be used in necessary cases.
You should bear in mind that these instruments are used only when necessary, in cases in which the baby is in distress or needs help out of the birth canal or if the baby fails to adapt to the pelvis or if the head is poorly positioned.
This is when the placenta is delivered (about 5-10 min after the birth of the baby).