fetal part then is permitted to descend. full dilation is reached when the cervix has widened enough to allow passage of the baby's 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. 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. friedman's 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 stages in the birth of the baby's head 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 opening. this is assisted by the additional maternal efforts of pushing, or bearing down, similar to defecation. the appearance of the fetal head at the vaginal opening is termed 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. 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: placental expulsion further information: umbilical cord and placental expulsion 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. active management is the administration of a uterotonic drug within one minute of fetal delivery, controlled traction of the umbilical cord and fundal massage after delivery of the placenta, followed by performance of uterine massage every 15 minutes for two hours. in a joint statement, world health organization, the international federation of gynaecology and obstetrics and the international confederation of midwives recommend active management of the third stage of labour in all vaginal deliveries to help to prevent postpartum haemorrhage. delaying the clamping of the umbilical cord for at least one minute or until it ceases to pulsate, which may take several minutes, improves outcomes as long as there is the ability to treat jaundice if it occurs. for many years it was believed that late cord cutting led to a mother's risk of experiencing significant bleeding after giving birth, called postpartum bleeding. however a recent review found that delayed cord cutting in healthy full-term infants resulted in early haemoglobin concentration and higher birthweight and increased iron reserves up to six months after birth with no change in the rate of postpartum bleeding. fourth stage: postpartum further information: postpartum period and puerperal disorder newborn rests as caregiver checks breath sounds. the fourth stage of labour is the period beginning immediately after childbirth, and extends for about six weeks. the terms postpartum and postnatal are often used for this period. the woman's body, including hormone levels and uterus size, return to a non-pregnant state and the newborn adjusts to life outside the mother's body. the world health organization (who) describes the postnatal period as the most critical and yet the most neglected phase in the lives of mothers and babies; most deaths occur during the postnatal period. following the birth, if the mother had an episiotomy or a tearing of the perineum, it is stitched. this is also an optimal time for uptake of long-acting reversible contraception (larc), such as the contraceptive implant or intrauterine device (iud), both of which can be inserted immediately after delivery while the woman is still in the delivery room. the mother has regular assessments for uterine contraction and fundal height, vaginal bleeding, heart rate and blood pressure, and temperature, for the first 24 hours after birth. some women may experience an uncontrolled episode of shivering or postpartum chills following the birth. the first passing of urine should be documented within six hours. afterpains (pains similar to menstrual cramps), contractions of the uterus to prevent excessive blood flow, continue for several days. vaginal discharge, termed "lochia", can be expected to continue for several weeks; initially bright red, it gradually becomes pink, changing to brown, and finally to yellow or white. at one time babies born in hospitals were removed from their mothers shortly after birth and brought to the mother only at feeding times. mothers were told that their newborn would be safer in the nursery and that the separation would offer the mother more time to rest. as attitudes began to change, some hospitals offered a "rooming in" option wherein after a period of routine hospital procedures and observation, the infant could be allowed to share the mother's room. as of 2020, rooming-in has increasingly become standard practice in maternity wards. early skin-to-skin contact kangaroo care by father in cameroon skin-to-skin contact (ssc), sometimes also called kangaroo care, is a technique of newborn care where babies are kept chest-to-chest and skin-to-skin with a parent, typically their mother, though more recently (2022) their father as well. this means without the shirt or undergarments on the chest of both the baby and parent. a 2011 medical review found that early skin-to-skin contact resulted in a decrease in infant crying, improved cardio-respiratory stability and blood glucose levels, and improved breastfeeding duration. a 2016 cochrane review also found that ssc at birth promotes the likelihood and effectiveness of breastfeeding. as of 2014, early postpartum ssc is endorsed by all major organisations that are responsible for the well-being of infants, including the american academy of pediatrics. the world health organization (who) states that "the process of childbirth is not finished until the baby has safely transferred from placental to mammary nutrition." 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 baby's father or other support person may also choose to hold the baby ssc until the mother recovers from the anaesthetic. 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 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 parent's room it has long been known that a mother's level of the hormone oxytocin 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. two studies found that "when the infant is clothed only in a diaper and placed in between the mother or father's breasts, chest-to-chest shown to reduce stress and anxiety in parents after interaction." discharge for births that occur in hospitals the who recommends a hospital stay of at least 24 hours following an uncomplicated vaginal delivery and 96 hours for a cesarean section. looking at length of stay (in 2016) for an uncomplicated delivery around the world shows an average of less than 1 day in egypt to 6 days in (pre-war) ukraine. averages for australia are 2.8 days and 1.5 days in the uk. while this number is low, two-thirds of women in the uk have midwife-assisted births and in some cases the mother may choose a hospital setting for birth to be closer to the wide range of assistance available for an emergency situation. however, women with midwife care may leave the hospital shortly after birth and her midwife will continue her care at her home. in the u.s. the average length of stay has gradually dropped from 4.1 days in 1970 to a current stay of 2 days. the cdc attributed the drop to the rise in health care costs, saying people could not afford to stay in the hospital any longer. to keep it from dropping any lower, in 1996 congress passed the newborns' and mothers' health protection act that requires insurers to cover at least 48 hours for uncomplicated delivery. labour induction and caesarean section main articles: caesarean section, labour induction, and delivery after previous caesarean section in many cases and with increasing frequency, childbirth is achieved through labour induction or caesarean section, also called a c-section. labour induction is the process or treatment that stimulates childbirth and delivery. inducing labour can be accomplished with pharmaceutical or non-pharmaceutical methods. inductions are most often performed either with prostaglandin drug treatment alone, or with a combination of prostaglandin and intravenous oxytocin treatment. caesarean section is the removal of the neonate through a surgical incision in the abdomen, rather than through vaginal birth. during the procedure the patient is usually numbed with an epidural or a spinal block, but general anaesthesia can be used as well. a cut is made in the patient's abdomen and then in the uterus to remove the baby. before the 1970s, once a patient delivered one baby via c-section, it was recommended that all of her future babies be delivered by c-section, but that recommendation has changed. unless there is some other indication, mothers can attempt a trial of labour and most are able to have a vaginal birth after c-section (vbac). induced births and elective cesarean before 39 weeks can be harmful to the neonate as well as harmful or without benefit to the mother. therefore, many guidelines recommend against non-medically required induced births and elective cesarean before 39 weeks. labour induction the 2012 rate of labour induction in the united states was 23.3 per cent, and had more than doubled from 1990 to 2010. by 2022 it had climbed to 32%. the american congress of obstetricians and gynecologists (acog) guidelines recommend a full evaluation of the maternal-fetal status, the status of the cervix, and at least a 39 completed weeks (full term) of gestation for optimal health of the newborn when considering elective induction of labour. per these guidelines,