Abstract

PIP: Both the fertility inhibiting effects of breastfeeding and the lactation inhibiting effects of hormonal contraceptives should be considered in developing postpartum family planning programs for lactating women. Because a high percentage of female contraceptive acceptors discontinue use within a year, the largest birth intervals may be achieved by delaying the initiation of contraception to take advantage of lactational infertility in the first postpartum months. Although evaluation of existing data on the effects of oral contraceptives on lactation is difficult, findings suggest that low-dose progestins may have a less detrimental effect on lactation than combined oral contraceptives. Depo-provera appears to enhance milk volume and duration of lactation, but the unknown side effects of transmission of steroids to the infant and changes in milk composition suggest caution in recommending it for nursing mothers. Results of research on possible effects of IUDs on lactation are conflicting and difficult to interpret, but possible mechanisms through prolactin secretion or oxytocin have been suggested for such an effect. Numerous methodological problems hamper efforts to evaluate evidence of the relationship of contraception to lactation to provide recommendations for family planning programs. The most prudent course where possible is to avoid giving hormonal contraceptives to the lactating woman. Where only hormonal contraceptives are acceptable, the best approach is probably to delay their use for at least 3 months postpartum to allow lactation to become established and the infant to mature.