Safety in Lactation: Combined hormonal contraceptives

Combined hormonal contraceptives (CHC) are a combination of an oestrogen and progestogen administered either orally, transdermally or vaginally (via a vaginal ring).
The oestrogen component of CHCs can have a significant effect on supressing milk production, especially in doses exceeding 30 micrograms ethinylestradiol, which normally precludes their use in breastfeeding mothers until weaning or for 6 months after birth. The oestrogen levels in currently available CHCs are not considered to be high enough to pose a risk of oestrogenic effects in infants.
Individual progestogens used in CHCs are not detailed here as the progestogen component is not considered to pose a risk to the infant or to lactation. This also applies to progestogens only used in combination with an oestrogen (drospirenone, norgestimate, nomegestrol and dienogest).
It is advised to avoid CHCs in the first 6 weeks postpartum due to possible effects on milk production and infant growth and increased risk of thromboembolism in the mother. Progestogen-only contraceptives are preferred at all stages of lactation.