Ethinyl estradiol-norethindrone has been assigned to pregnancy category X by the FDA. Animal studies have failed to reveal evidence of teratogenicity. Ethinyl estradiol-norethindrone is considered contraindicated during pregnancy.
Although some reports have suggested that oral contraceptive hormones may cause a variety of congenital malformations, recent studies (including a meta-analysis of prospective studies) have suggested that an association between oral contraceptive use and congenital malformations does not exist. Some progestins may cause masculinization of female infants. One case report has suggested that oral contraceptive hormones may cause choreoathetosis in infants exposed in utero.
A recent case control study has suggested a weak association between use of older high dose contraceptives (particularly those containing 1.0 mg of ethynodiol diacetate) and the occurrence of congenital limb defects. However, the authors concluded that "this weak causal relationship was probable in the past when relatively high doses of contraceptive pills were used. This risk is apparently minimized by the use of new type (e.g., D-norgestrel) and lower dose of contraceptive pills".