Pregnancy and birth While pregnancy is the beginning of many physical and emotional changes, you will be pleased to know that, unless you have been advised otherwise for medical reasons, it is safe to have sex while pregnant. In fact, you may find sex is better than ever. Throughout your pregnancy it's normal for your desire for sex to change. During the first trimester, you may experience the common symptoms of tiredness and nausea, both of which can lessen sexual interest. The good news is that this will probably be followed by renewed interest in the second trimester, with the return of feelings of well-being, energy, vitality and libido! Bear in mind though, that towards the end of your pregnancy, interest may wane again due to increased size and a general lack of desire. Is it safe to have sex during pregnancy?