Return of fertility in lactating and non-lactating women.

The return of fertility post-partum and the incidence of pregnancy were studied in 74 mothers in Chile who chose not to breastfeed and who wanted another pregnancy promptly (Group I) and 143 mothers who practiced exclusive lactation and decided not to use contraceptives (Group II). Women who breastfed had much lower pregnancy rates than those who did not. During the 1st 6 months of the study there were 53 (72%) pregnancies among the Group I women adn no pregnancies among the Group II mothers. Only 16 (11%) women in Group II discontinued the study because of inadequate milk secretion. The low rate of pregnancy and the low rates of inadequate milk secretion in Group II appear related to the special efforts made to promote breastfeeding and give proper instruction to the mothers in this group. The successful lactation is attributed to a high suckling frequency night feedings ample mother and child skin-to-skin contact avoidance of bottle feeding for as long as possible and the clinical staffs regular emotional support and encouragement to the nursing mother. (authors)