Reproductive function and contraception in the postpartum period

The postpartum period is a time of major cellular and hormonal change enabling the return of pelvic organs and the hypothalamic-pituitary-ovarian axis to the nonpregnant state. Breast-feeding modifies this change and maintains the endocrine profile and uterine endometrium in a "static" state. In nonlactating women, menstruation returns on average by day 55 to 60 postpartum and ovulation returns on average by day 40 to 50 postpartum. Breast-feeding prolongs the return of menstruation to some 8 to 15 months postpartum and the first ovulation on average was between 30 to 40 weeks postpartum. However, in breast-feeding women, the return of menstruation and ovulation can be quite variable and is influenced by the pattern of breast-feeding, in particular, the intensity and pattern of suckling. There is concern that breast-feeding, although an effective contraceptive on a wide population scale, is unpredictable for the individual. An overall pregnancy rate of 2 to 10 per cent during lactational amenorrhea has been reported. Barrier methods, intrauterine contraceptive devices, and progestogen-only contraceptives are some of the highly effective and most commonly used additional methods of contraception by lactating women. Other methods of contraception during this period include the use of periodic abstinence and combined oral contraceptives. This paper provides an overview of postpartum reproductive function in relation to breast-feeding and the use of contraception in this unique period.