Many rheumatic diseases affect women of childbearing age. It is well known that during pregnancy, some patients with inflammatory arthritis such as rheumatoid arthritis go into remission, whereas in others, pregnancy aggravates disease activity. Unfortunately, the flares of rheumatic diseases during pregnancy may result in fetal loss, intrauterine growth retardation, and premature delivery. Furthermore, during pregnancy, anti-rheumatic drugs used to control disease activity may lead to fetal complications. In this review, the effects of pregnancy on the disease and the effects of disease on the fetus are discussed first. The effects of biological and non-biological disease-modifying anti-rheumatic drugs on fertility, pregnancy, and lactation are then summarized. Physicians dealing with rheumatic diseases need to be aware of the potential adverse effects of these medications and discuss the risks and benefits of drugs during pregnancy and lactation with their patients in detail.