Is it safe to take prempro (conjugated estrogens and medroxyprogesterone) while pregnant or breastfeeding?

Not recommended: Prempro (conjugated estrogens and medroxyprogesterone) is a combination estrogen / Progesterone medication indicated for postmenopausal hormone replacement. The doses of estrogen and Progesterone are a tiny fraction of what is typically produced by a reproductive age women. While prempro (conjugated estrogens and medroxyprogesterone) would be of no particular benefit (and is contra-indicated) during pregnancy and breastfeeding, it is unlikely to be harmful.