Sexually transmitted diseases, also known as STDs, are common in the developing world. Management of STDs in pregnancy in many developing countries has been complicated by the lack of simple and affordable diagnostic tests. Pregnant women can become infected with the same sexually transmitted infections as women who are not pregnant. This points out that pregnancy does not provide women or their babies any additional protection against STDs. Many STDs have no symptoms, so women may not know they are infected and this relates to a significant impact on the pregnant woman and her fetus and neonate. Infection at various stages of pregnancy may result in severe maternal disease, congenital defects, premature delivery, or neonatal infection. Some of these problems may be seen at birth, others may not be discovered until months or years later. Most of these complications can be prevented if the mother receives regular medical care during pregnancy. This includes tests for STDs starting early in pregnancy and repeated close to delivery, as needed. Therefore, it is important to detect bacterial and other causes of STDs in pregnancy so that possible complications and consequences can be predicted and managed.