However, the duration of active first stage (from 5 cm until full cervical dilatation) usually does not extend beyond 12 hours in the first labour("primiparae"), and usually does not extend beyond 10 hours in subsequent labours ("multiparae").Dystocia of labour, also called "dysfunctional labour" or "failure to progress", is difficult labour or abnormally slow progress of labour, involving progressive cervical dilatation or lack of descent of the fetus. Friedmans Curve, developed in 1955, was for many years used to determine labour dystocia. However, more recent medical research suggests that the Friedman curve may not be currently applicable. Second stage: fetal expulsion
The expulsion stage begins when the cervix is fully dilated, and ends when the baby is born. As pressure on the cervix increases, a sensation of pelvic pressure is experienced, and, with it, an urge to begin pushing. At the beginning of the normal second stage, the head is fully engaged in the pelvis; the widest diameter of the head has passed below the level of the pelvic inlet. The fetal head then continues descent into the pelvis, below the pubic arch and out through the vaginal introitus (opening). This is assisted by the additional maternal efforts of "bearing down" or pushing, similar to defecation. The appearance of the fetal head at the vaginal orifice is termed the "crowning". At this point, the mother will feel an intense burning or stinging sensation. When the amniotic sac has not ruptured during labour or pushing, the infant can be born with the membranes intact.
They therefore conclude that "women should be free to eat and drink in labour, or not, as they wish. "At one time shaving of the area around the vagina, was common practice due to the belief that hair removal reduced the risk of infection, made an episiotomy (a surgical cut to enlarge the vaginal entrance) easier, and helped with instrumental deliveries. It is currently less common, though it is still a routine procedure in some countries even though a systematic review found no evidence to recommend shaving. Side effects appear later, including irritation, redness, and multiple superficial scratches from the razor. Another effort to prevent infection has been the use of the antiseptic chlorhexidine or providone-iodine solution in the vagina. Evidence of benefit with chlorhexidine is lacking. A decreased risk is found with providone-iodine when a cesarean section is to be performed. Forceps or vacuum assisted delivery
An assisted delivery is used in about 1 in 8 births, and may be needed if either mother or infant appears to be at risk during a vaginal delivery. The methods used are termed obstetrical forceps extraction and vacuum extraction, also called ventouse extraction. Done properly, they are both safe with some preference for forceps rather than vacuum, and both are seen as preferable to an unexpected C-section. While considered safe, some risks for the mother include vaginal tearing, including a higher chance of having a more major vaginal tear that involves the muscle or wall of the anus or rectum.