PIP: About 90% of women give their infants breast milk. It is the best nutrition for them and prevents infection. Lactation protects against pregnancy for at least 6 months. After 6 months, breast-feeding mothers need a reliable contraceptive method. Their 1st choice should be nonhormonal contraception, such as IUDs, barrier methods, spermicides, and sterilization. Some women want hormonal methods because they are convenient and effective. Progestin-only methods are the preferable hormonal contraception since they are safe for mother and infant. They include the progestin-only pill; the subdermal implant, Norplant; and injectables with norethisterone enanthate and depot-medroxyprogesterone acetate (DMPA). The mechanisms by which progestin-only methods prevent pregnancy are thickening of the cervical mucus, trimming the uterine lining, and, sometimes, suppressing ovulation. Breast-feeding and family planning specialists do not agree on when lactating women should begin using the progestin-only methods. IPPF says they can start as early as 6 weeks' postpartum. Other specialist groups claim that women can wait up to 4 months' postpartum. A study in Argentina reveals no harm to infants when mothers began progestin-only methods at 1 week postpartum. The initial higher dose of injectables is a special concern. In addition to timing, providers and clients must also consider the feasibility of returning to a clinic for contraception. A Swedish study shows no detectable progestin in the blood of infants whose mothers use the progestin-only pill, suggesting that infants metabolize the progestin. Progestin-only methods do not reduce breast milk production and may even increase it. DMPA may affect the concentration of lactose, calories, and nitrogen in breast milk, but these changes should not be a problem in areas where women are adequately nourished. Further research of DMPA and breast milk component levels in populations with less than ideal nutrition levels is needed. Progestins appear to cause no longterm harmful effects.