Description

A full-term pregnancy is considered to be 280 days, nine calendar months or ten lunar months calculated from the first day of the last menstrual period. This is a fairly arbitrary number that may, in fact, vary with genetic differences and depends on a normal menstrual cycle, which varies considerably from woman to woman. The average actual length from conception to birth is estimated as 267 days. Childbirth is a natural process,

Childbirth in stage 2. The baby's head is crowning and about to emerge from the vagina.

(Illustration by Hans & Cassidy.)

and it, too, varies among women. Despite what the obstetrical texts say about what to expect, there are many variations that make each woman's experience hers alone. The whole process averages about 14 hours for first-time mothers and about eight hours for mothers in their subsequent pregnancies.

Labor can be described in terms of a series of stages.