I've been on pelvic rest for 5 months and today my doctor said my hubby and I can start having sex but he has to wear a condom. Something about a hormone in seman that can cause cramping and contractions. She told me if I started cramping or have contractions after orgasm to not have sex again until after baby comes.
Semen causes the uterus to contract. Sex is perfectly fine unless they tell u otherwse.
Unless your Ob put you on pelvic rest, yes. Sex is safe. More than that it's important for you as a woman and you as a couple to stay connected. If you are concerned about it triggering labor, such as you're at risk of preterm check in with your Ob & ask if you are on pelvic rest. :)