In the US, the definition of active labour was changed from 3 to 4 cm, to 5 cm of cervical dilation for multiparous women, mothers who had given birth previously, and at 6 cm for nulliparous women, those who had not given birth before. This was done in an effort to increase the rates of vaginal delivery.Health care providers may assess a labouring mothers progress in labour by performing a cervical exam to evaluate the cervical dilation, effacement, and station. These factors form the Bishop score. The Bishop score can also be used as a means to predict the success of an induction of labour. During effacement, the cervix becomes incorporated into the lower segment of the uterus. During a contraction, uterine muscles contract causing shortening of the upper segment and drawing upwards of the lower segment, in a gradual expulsive motion. The presenting fetal part then is permitted to descend. Full dilation is reached when the cervix has widened enough to allow passage of the babys head, around 10 cm dilation for a term baby. A standard duration of the latent first stage has not been established and can vary widely from one woman to another.
It is advised that the newborn be placed skin-to-skin with the mother following vaginal birth, or as soon as the mother is alert and responsive after a Caesarean section, postponing any routine procedures for at least one to two hours. The babys father or other support person may also choose to hold the baby SSC until the mother recovers from the anesthetic.The WHO suggests that any initial observations of the infant can be done while the infant remains close to the mother, saying that even a brief separation before the baby has had its first feed can disturb the bonding process. They further advise frequent skin-to-skin contact as much as possible during the first days after delivery, especially if it was interrupted for some reason after the delivery.La Leche League advises a women to have a delivery team which includes a support person who will advocate to assure that:

The mother and her baby are not separated unnecessarily
The baby will receive only her milk
The baby will receive no supplementation without a medical reason
All testing, bathing or other procedures are done in the parents roomIt has long been known that a mothers level of the hormone oxytocin, sometimes called  "the love hormone", elevates in a mother when she interacts with her infant. In 2019, a large review of the effects of oxytocin found that the oxytocin level in fathers  that engage in SSC is increased as well.