Teratogens also known as agents of birth defects , which can impair normal prenatal development. When women takes drugs during pregnancy period , their babies are often experience prenatal complications . some drugs which cause harm to foetus are cocaine, heroin, marijuana , tranquilizers etc.the effect of teratogen on child depends , what time the child exposed to that teratogen, the dose of teratogen, genetic constitution of the teratogens etc.

Anabolic steroids

Steroids are chemical substances .they are found in human body .some of them are used as medicine for the treatment of asthma, rheumatoid arthritis etc.Anabolic steroids are synthetic steroids  related to male sex hormones. This help to growth of bones, muscles, hair pattern etc. athletes and body builders are used steroids for building up their body. Some important anabolic steroids are anadrol, dianobol, winstol, durabolin etc. the excess use of anabolic steroid leads to infertility, breast development, shrinking of testes etc. in males. The excessive use of steroids in females leads to heart attack , enlargement of heart valves, cancer, acne and cyst.