Reproductive Hazards Summary Both the male and female reproductive systems play a role in pregnancy. Problems with these systems can affect fertility and the ability to have children. Something that affects reproductive health is called a reproductive hazard. Examples include: Radiation Metals such as lead and mercury Chemicals such as pesticides Cigarettes Some viruses Alcohol For men, a reproductive hazard can affect the sperm. For a woman, a reproductive hazard can cause different effects during pregnancy, depending on when she is exposed. During the first 3 months of pregnancy, it might cause a birth defect or a miscarriage. During the last 6 months of pregnancy, it could slow the growth of the fetus, affect the development of its brain, or cause premature labor. National Institute of Environmental Health Sciences Clinical Trials ClinicalTrials.gov: Male Reproductive Hazards National Institutes of Health ClinicalTrials.gov: Pregnancy Hazards National Institutes of Health Specifics Hair Treatments and Pregnancy Organization of Teratology Information Specialists Mercury and Pregnancy March of Dimes Birth Defects Foundation Methylmercury and Pregnancy Organization of Teratology Information Specialists Paint and Pregnancy Organization of Teratology Information Specialists Pesticides and Pregnancy Organization of Teratology Information Specialists Pregnancy and Radiation Exposure Health Physics Society Radiation and Pregnancy March of Dimes Birth Defects Foundation X-Rays, Pregnancy and You Food and Drug Administration Start Here Pregnancy Precautions: FAQs on Pregnancy Hazards Nemours Foundation Journal Articles Female reproductive health Male reproductive health Patient Handouts Tests for Reproductive Health Department of Health and Human Services, Office on Women’s Health