Post partum

A postpartum (or postnatal) period begins immediately after the birth of a child and extends for about six weeks, as the mother's body, including hormone levels and uterus size, returns to a non-pregnant state. Less frequently used are the terms puerperium or puerperal period. 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. In scientific literature, the term is commonly abbreviated to Px, where x is a number; for example, "day P5" should be read as "the fifth day after birth". This is not to be confused with the medical nomenclature that uses G P to stand for number and outcomes of pregnancy (gravidity and parity).

Upon their entry to the air-breathing world, newborns begin to adjust to life outside the uterus.

A woman giving birth in a hospital may leave as soon as she is medically stable, which can be as early as a few hours postpartum, though the average for a vaginal birth is one to two days, and the average caesarean section postnatal stay is three to four days. During this time, the mother is monitored for bleeding, bowel and bladder function, and baby care. The infant's health is also monitored.

After the fourth stage of labor the uterus can be palpated at the level of the navel (belly button). The uterus continues to contract and shrink in size so that two weeks postpartum, it again resides in the pelvis. The tissue lining the uterus begins to regenerate and by day seven postpartum the endometrial glands are restored. By day sixteen, the endrometrial lining has been completely restored except at the site of placental attachment. This site within the uterus undergoes changes that include contractions of vascular smooth muscles and myometrium. This encourages hemostasis.

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