Births

Birth, in human biology, is the act of delivering a baby from the uterus at the end of gestation, marking the beginning of extrauterine life. In humans, gestation typically lasts about 40 weeks from the last menstrual period, with full term defined as 37 to 42 weeks. The process, known as parturition, is driven by hormonal changes that coordinate uterine contractions, cervical dilation, and fetal descent.

Parturition is commonly divided into three stages: the first stage involves dilation and effacement of the cervix; the second stage is the delivery of the baby; the third stage encompasses delivery of the placenta and cessation of uterine bleeding.

Birth can occur via vaginal birth or cesarean section, with assisted vaginal delivery using forceps or vacuum extraction employed in some cases. Medical decisions are based on maternal and fetal health, and interventions aim to reduce risks to both.

After birth, the newborn is assessed for health and well-being, and is recorded in civil registries. Birth certificates document the date, place, and parentage, and help determine access to services and legal status.

In demography, births form a key statistic, with measures such as the birth rate (births per 1,000 people per year) and the total fertility rate used to describe population growth. Factors influencing birth patterns include health care, education, economic conditions, and social norms.