Premature birth Sometimes it happens that a pregnant woman who has begun labor cannot get to a medical facility before delivery begins. In this case, call an ambulance immediately. First aid in this situation consists of assisting the woman before, during and after childbirth, as well as in caring for the newborn. Anatomy and physiology of childbirth Before birth, the developing fetus usually occupies a head-down position in the uterus (womb). The fetus is surrounded by a membrane containing amniotic fluid (amniotic membrane) and connected to the uterine placenta by the umbilical cord. When a woman's body is ready for childbirth, the uterus begins to contract regularly. Contractions are a rhythmic contraction of the muscles of the uterus, moving in waves. This period is called labor. The time between contractions is measured from the start of one to the start of the next. After labor, the membrane containing amniotic fluid may rupture. Gradually, contractions become more intense and frequent, and the cervix - the opening of the uterus leading to the birth canal (vagina) - dilates to accommodate the passage of the fetus. The maternity hospital can last up to 16 hours or more for a woman who is giving birth for the first time, but it can be much shorter for a woman who already has children. Sudden labor is more likely to occur in a woman who has already given birth, because in this case labor progresses much faster. The less time remains before birth, the more frequent, longer and stronger the contractions become. During delivery, uterine contractions, usually occurring at intervals of less than two minutes, begin to push the fetus down the birth canal and out. Complications are rare and most births are a normal and natural process.