Usually, you can have sex well into your third trimester, as long as you’re having no problems with your pregnancy. But you may not always want to. During the early stage of pregnancy, changing hormones, new weight gain and decreased energy levels may take their toll on sexual desire. Lack of interest may continue through the first trimester, when exhaustion and nausea are most likely to occur.

During the second trimester, increased blood flow to your sexual organs and breasts may rekindle your desire. It may even increase your normal interest in sex. As you enter your final trimester, however, interest may wane in terms of their safety during pregnancy. But most medications haven’t been studied on pregnant women. Therefore, it isn’t known for certain if they cause damage to growing fetuses or can affect a child later in life.
Some medications have been shown to be extremely harmful to a developing fetus, even in the early weeks of pregnancy. Some of the most dangerous drugs include:
* The acne drug isotretinoin (Accutane)
* The multiuse drug thalidomide (Thalomid)
* The psoriasis drug acitretin (Soriatane)
If you’re taking one of these medications, avoid becoming pregnant until you discontinue its use. Your health care provider will advise you on the best way to stop taking a medication and how long you may need to wait before it’s safe to conceive. Don’t restart a drug without talking to your health care provider.