(Combined Contraceptive Estrogen & Progestins)

Contraceptive combination of a estrogen (ethinylestradiol, estradiol or mestranol) and a progestogen drug derived from 19-nor testosterone (desogestrel, drospirenone, etonogestrel, levonorgestrel, norelgestromin, norethindrone ...), that may be marketed as oral pills (combined oral contraceptive: COC), vaginal rings (duration 3 weeks), transdermal patches (duration 3 weeks) or subcutaneous implants (duration 3 years).

During breastfeeding, progestogen-only contraceptives are preferable to those combined with oestrogen and, in this case, those with the lowest oestrogen dose. ^{(Sridhar 2017, CDC 2016, 2013 and 2010, WHO 2015, Altshuler 2015, Bhardwaj 2015, Berens 2015, CLM 2012, Amir 2011, FFPRHC 2004, WHO 2002, Moretti 2000, WHO 1988)}

If a COC is taken during breastfeeding, it is advisable not to start before one and a half months after delivery and to monitor milk production through the infant's growth^{. (Moretti 2000)}

Non-hormonal methods are the first choice for the first 4-6 weeks postpartum. ^{(Berens 2015, Mwalwanda 2013, Rowe 2013)}

Several authors have found no negative effects on breast milk production or infant weight gain when COCs are started after the first 2, or better 6, weeks postpartum. ^{(Tepper 2015, Bahamondes 2013, Espey 2012, Toddywalla 1977)}

No clinical, physical or psychomotor development problems have been observed in the short or long term (8 years) in infants whose mothers took combined oral contraceptives. ^{(Lopez 2015, Nilsson 1986)}, except for a few cases of transient gynaecomastia in infants published years ago. ^{(Madhavapeddi 1985, Nilsson 1978, Marriq 1974, Curtis 1964)}

Hormonal contraceptives, both combined and progestogen-only, do not alter the composition of milk, either in terms of minerals (Mg, Fe, Cu, Ca, P) or in terms of fat, lactose, protein or calories. ^{(Urzica 2013, Dórea 2000, 1999 and 1998, Costa 1992)}

Other authors have found shorter breastfeeding duration and/or decreased milk production and/or lower weight gain in infants with the use of COCs, especially if used before 6 weeks postpartum. ^{(Karlsson 2025, Goulding 2018, WHO 1988, Nilson 1986, Diaz 1983, Guiloff 1974, Miller 1970, Kora 1969, Kaern 1967)} 

American Academy of Paediatrics: COCs are usually compatible with breastfeeding. ^{(AAP 2001)}

ESTROGENS are excreted into the breast milk in no or small amount. ^{(Perheentupa 2004, Betrabet 1986, Nilsson 1978)}

There is low quality evidence that estrogen-containing pills may decrease milk production or the duration of breastfeeding, especially if given during the first few weeks postpartum and with a daily dose equal to or greater than 30 micrograms (0,03 mg) diarios. ^{(Moses 2009, WHO 2002, AAP 2001, WHO 1988, Nilsson 1986, Tankeyoon 1984, Díaz 1983, Peralta 1983, Croxatto 1983, Guiloff 1974, Kaern 1967)}

Estrogens, alone or associated with progestogens, have been used in the treatment of excess milk production ^{(Johnson 2020)} and to suppress lactation ^{(Louviere 1975, Piya 2004, Balmer 1971)}, although with low effectiveness. ^{(Kaern 1967)}

High doses of oestrogen during adolescence have no effect on subsequent breastfeeding. ^{(Jordan 2007)}

PROGESTOGENS are excreted into breast milk in clinically non-significant amount ^{(Croxatto 1987, Betrabet 1987, Nilsson 1977)} and no problems have been observed in infants whose mothers were treated with this medication. ^{(Roy 2020, Bahamondes 2013, Dutta 2013, Shaamash 2005, Bjarnadóttir 2001, Díaz 1987)}

When measured, the plasma progestogen levels of these infants were very low. ^{(Bassol 2002, Patel 1994, Betrabet 1987, Diaz 1987, Nilsson 1977)}

See below the information of this related group:

• ATC G03AA & G03AB: Hormonal Contraceptives. Estrogens & Progestogens