Synthetic progestin similar to progesterone that is used in uterine bleeding, dysmenorrhea, infertility and contraception.For contraception is used as a single drug or in combination with estrogen (e.g. Estradiol + Medroxyprogesterone).For oral use or long-acting injectable administration (Intramuscular or subcutaneous). It is excreted into breast milk in clinically non-significant amount, and, no problems have been observed in infants whose mothers who were treated with this medication. Plasma levels of these infants were undetectable or very low.There may be increased prolactin and milk production in women who receive medroxyprogesterone. Although it has not been shown effects on production and duration of breastfeeding when administered at any time postpartum, it is still controversial on if it really decreases milk production when progestins are used before a fully establishment of breastfeeding has occurred. Therefore, experts’ protocols by WHO and ABM advise to avoiding it until breastfeeding is fully developed (4-6 weeks). During lactation progestin-only drugs are preferred or in combination with estrogen for birth control, but whatever, the ones with the lower doses of estrogen should be used.For the first 6 weeks postpartum, non-hormonal methods are of choise. Hormone containing contraceptives do not affect the composition of milk, minerals (Mg, Fe, Cu, Ca, P) fat, lactose and calories but only a few the proteins. WHO List of Essential Medicines 2002: rates it as compatible with breastfeeding after the 6th postnatal week.