In some countries of Europe, doctors commonly prescribe inhaled nitrous oxide gas for pain control, especially as 53% nitrous oxide, 47% oxygen, known as Entonox; in the UK, midwives may use this gas without a doctors prescription. Opioids such as fentanyl may be used, but if given too close to birth there is a risk of respiratory depression in the infant.Popular medical pain control in hospitals include the regional anaesthetics epidurals (EDA), and spinal anaesthesia. Epidural analgesia is a generally safe and effective method of relieving pain in labour, but has been associated with longer labour, more operative intervention (particularly instrument delivery), and increases in cost. However, a more recent (2017) Cochrane review suggests that the new epidural techniques have no effect on labour time and the use of instruments or the need for C-section deliveries. Generally, pain and stress hormones rise throughout labour for women without epidurals, while pain, fear, and stress hormones decrease upon administration of epidural analgesia, but rise again later. Medicine administered via epidural can cross the placenta and enter the bloodstream of the fetus. Epidural analgesia has no statistically significant impact on the risk of caesarean section, and does not appear to have an immediate effect on neonatal status as determined by Apgar scores. Augmentation
Augmentation is the process of stimulating the uterus to increase the intensity and duration of contractions after labour has begun. Several methods of augmentation are commonly been used to treat slow progress of labour (dystocia) when uterine contractions are assessed to be too weak.
This is referred to as "delivery en caul". Complete expulsion of the baby signals the successful completion of the second stage of labour. Some babies, especially preterm infants, are born covered with a waxy or cheese-like white substance called vernix. It is thought to have some protective roles during fetal development and for a few hours after birth. The second stage varies from one woman to another. In first labours, birth is usually completed within three hours whereas in subsequent
labours, birth is usually completed within two hours. Second-stage labours longer than three hours are associated with declining rates of spontaneous vaginal delivery and increasing rates of infection, perineal tears, and obstetric haemorrhage, as well as the need for intensive care of the neonate. Third stage: placenta delivery
The period from just after the fetus is expelled until just after the placenta is expelled is called the third stage of labour or the involution stage. Placental expulsion begins as a physiological separation from the wall of the uterus. The average time from delivery of the baby until complete expulsion of the placenta is estimated to be 10–12 minutes dependent on whether active or expectant management is employed. In as many as 3% of all vaginal deliveries, the duration of the third stage is longer than 30 minutes and raises concern for retained placenta.Placental expulsion can be managed actively or it can be managed expectantly, allowing the placenta to be expelled without medical assistance.