Premature introduction of progestin-only contraceptive methods during lactation

Abstract

Experts on contraceptive technology concur that progestin-only methods can be used safely during lactation. However, very few studies exist of the effects on lactation of the introduction of progestin-only methods prior to the sixth postpartum week. Since progesterone withdrawal is the likely stimulus that initiates lactogenesis, it appears necessary for natural progesterone levels to decline to baseline before a progestin-only contraceptive is initiated. Therefore, the use of such contraceptive methods should be delayed for at least 3 days after the birth. Non-hormonal methods remain the first choice category of contraceptive methods for breastfeeding women, since there is no possibility that they will interfere with lactation. Progestin-only methods comprise a viable and often desirable next choice category, although the timing of their commencement must be determined with care in order to support lactation.

PIP: All major international family planning organizations have endorsed the use of progestin-only contraceptive methods once lactation has been established. Prospective, multicenter studies of infants of acceptors of progestin-only pills, injections, and implants have found no deleterious effects of the drug on infant growth and development; however, women enrolled in these trials did not initiate method use until at least the sixth postpartum week. Of concern is a recent trend toward administration of progestin subdermal implants and injectables to women prior to their discharge from the hospital (i.e., 0-72 hours after delivery). Since progesterone withdrawal is the likely stimulus that initiates lactogenesis, natural progesterone levels need a chance to decline to baseline before progestin contraceptive use is initiated. Moreover, the immature neonatal liver may have difficulties metabolizing exogenous steroids, the binding capacity of plasma is low, and the immature kidney may be inefficient in steroid excretion. Use of progestin-only contraceptive methods should be delayed for at least 3 days (optimally, until 6 weeks) after birth so lactation can become established. Nonhormonal methods remain the first choice for breast-feeding women, given the lack of potential to interfere with lactation, while progestin-only agents are a viable second choice.