Birth control pill that contains the combination of an estrogen (Ethinyl estradiol) and a progestin (Levonorgestrel) for oral use. Ethinylestradiol is a synthetic estrogen with similar action than estradiol. Used in combination with progestogens for contraception.Ethinylestradiol is excreted into the breast milk in no or small amount.There is evidence (albeit inconsistent) that estrogen-containing pills may decrease milk production, especially during the first few weeks postpartum with a daily dose above 30 micrograms of ethinyl estradiol.It may reduce the protein content of the milk.No problems have been observed in infants whose mothers were treated, except some cases of transient gynecomastia in infants whose mothers were receiving a higher dose than usual. Levonorgestrel is a progestin, and active metabolite which is isomer of norgestrel, both derived from nortestosterone. It is excreted into breast milk in clinically non-significant amount and no problems have been observed in infants whose mothers were treated. The plasma levels in these infants were very low. With other similar combined contraceptives no differences have been observed in the frequency of breastfeeding or the amount of milk produced or weight gain of breastfed infants compared to other contraceptive methods (intrauterine devices, isolated progestogens). However, it would be advisable to avoid them until breastfeeding is well established (4-6 weeks). During lactation, progestin-only contraceptive pills are preferred to Estrogen containing ones, otherwise, the lowest estrogen dose should be used.During the first 6 postpartum weeks, non-hormonal methods are in the first line of choice. 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.