美雌醇 + 炔诺酮

Birth control pill that contains the combination of an estrogen (Mestranol) and a progestin (Noretindrone) for oral use. Mestranol is a synthetic estrogen that is metabolized to Ethinylestradiol with similar actions as estradiol.

MESTRANOL:

• A latest up date no published data on excretion in breast milk, found were found. However, it is known that its metabolite Ethinylestradiol is excreted into 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 one isolated case of transient gynecomastia. ^{(Curtis 1964)}

NORETHINDRONE:

• Norethisterone or Nornorethindrone is a contraceptive progestogen derived from 19-northstastterone used as a single product or associated with ethinylestradiol. Oral administration daily or in intramuscular injection every 8 weeks.
• It is excreted in breast milk in clinically significant amount ^{(Betrabet 1987, Toddywalla 1980, Saxena 1977)} and no problems have been observed in infants whose mothers took it. ^{(WHO 1994, Shaaban 1991, Giner 1976, Karim 1971)}
• Plasma levels of these infants were undetectable or very low.^{(Betrabet 1987)}
• No alterations have been observed in the amount or composition of breast milk in mothers treated with norethindrone. ^{(Giner 1976)}
• WHO List of Essential Medicines 2002: rates it as compatible with breastfeeding after the 6th postnatal week. ^{(WHO/OMS 2002)}

During breastfeeding progestin-only contraceptives are preferable to those combined with estrogen and, in this case, those with a lower dose of estrogen. ^{(CDC 2016, WHO/OMS 2015, Altshuler 2015, Berens 2015, CLM 2012, Moretti 2000)}

For the first 4-6 weeks postpartum, non-hormonal methods are the first choice, followed by IUDs and progestogen implants. ^{(Berens 2015, Mwalwanda 2013, Rowe 2013, CLM 2012)}

See below the information of these related products:

• Estradiol (Fairly safe. Mild or unlikely adverse effects. Compatible under certain circumstances. Follow-up recommended. Read Commentary.)
• Ethinylestradiol (Fairly safe. Mild or unlikely adverse effects. Compatible under certain circumstances. Follow-up recommended. Read Commentary.)
• Norethisterone (Safe product and/or breastfeeding is the best option.)