Sex can be painful throughout pregnancy, not just in the first trimester. For the most part, it's because of totally normal changes happening in your body. Unless you have an infection, here are a few reasons why sex in the first trimester might hurt: Your vagina is dry because of hormonal changes. Sex in pregnancy is usually fine, but many men find their sexual relationship changes, especially in early pregnancy. Read more in Sex during pregnancy can feel quite different from how it felt before. Things you can do. It's perfectly safe to have sex during pregnancy unless your doctor or midwife Some couples find having sex very enjoyable during pregnancy, while others simply feel they don't want to. You will probably need to find different positions. But things will be different — the drastic changes in your.