The benefit of lactation amenorrhea as a contraceptive.

A group of 148 lactating women who delivered normally at El-Galaa Hospital, Cairo, were followed up monthly for 1 year to study the pattern of lactation amenorrhea, the return of menstruation and ovulation, and the incidence of pregnancy. By the end of the sixth week postpartum, only 1.3 percent of the women had begun menstruating; the percentage gradually increased to 60.2 percent by the end of the first year. The amount of blood loss and the duration of menstruation increased gradually until the fourth postpartum menstrual period. Ovulation had occurred in 58.1 percent and pregnancy in 26.1 percent of all cases at the end of the 12th postpartum month. Among menstruating, lactating mothers, ovulation occurred in 86.5 percent and pregnancy in 32.6 percent, while in amenorrheic, lactating mothers only 6.1 percent had become pregnant at 1 year postpartum.