I have heard many a provider order a prescription for sex over the course of my long career as a perinatal nurse. I have even echoed it. It's usually the poor 40+ weeker, mother of two more at home. She is beyond caring about anything but delivering her baby. It may be possible that if the cervix is ripe, the semen contains certain hormones that might initiate labor. It couldn't hurt....
How many times have I had the question posed? Won't it hurt her? Will the baby know what we're doing? Will it hurt the baby? Is it okay to have sex when you are pregnant?
If your pregnancy is healthy and normal, without any bleeding or unusual discharge and your provider hasn't said "DON'T DO IT, you can have sex as long into the pregnancy as you'd like and as often too. Sex doesn't cause miscarriages, although if you are bleeding your doctor will probably say "no". It's most likely a problem with the pregnancy that causes miscarriages, but doctors know how guilty you'd feel if you had sex and then miscarried, so that's why the "no" if you are bleeding or threatening to miscarry. Some folks have sex and wake up to blood on the sheets. It's either an inconsequential bleeding episode which resolves itself or a very cruel coincidence. Sex doesn't cause miscarriages.
Sex doesn't affect your baby one way or another. The baby has no idea what you're doing. Furthermore that squirt is protected with layers of insulation to keep him safe. Fluid and uterine muscle and your abs too. Whatever position you find yourself in ( or not ) is perfectly okay during pregnancy.
Oral sex is okay too and it might even be more comfortable for you. Just make sure that your partner refrains from blowing air into the vagina because rarely but occasionally that may cause an air embolism which could be very dangerous to you and the baby. Most pregnant women aren't interested much in anal sex and it really isn't recommended. Hemorrhoids certainly wouldn't improve and any bacteria from the rectum could be spread to the vagina which may cause infection.
It's fine to have sex. It's great to have orgasms. What works best for the both of you, works best for the pregnancy and that will be true throughout your parenting years. And remember, there are many ways to say " I love you."