Safety in Lactation: Progestogens

Progestogens, especially medroxyprogesterone (MP) and norethisterone (NT), are used mainly as depot injectable contraceptives and administered every 4 weeks (NT) to 12 weeks (MP). For this indication they are not normally commenced until 6 weeks postpartum.
Use in endometrial, breast or renal cell cancer is normally by daily, oral administration of higher cumulative doses than used for contraception. There are no published data on their effects in infants or on lactation when used in this way.
Progestogens can suppress early lactation. Their use can be delayed for 6 weeks postpartum, until breastfeeding is fully established, although this may present an unacceptable clinical risk to the mother in this situation.