This sheet is about paternal exposures in a pregnancy and while breastfeeding. This information should not take the place of medical care and advice from your healthcare provider. What is a “paternal exposure”? A paternal exposure is anything a male parent or sperm donor is exposed to before a pregnancy is conceived, while trying to conceive pregnancy, or after their partner is pregnant. This includes things such as substances of use (alcohol, tobacco, marijuana, opioid misuse), …