In fact, in the end, it may help in bringing on labour.
Sex and sexual intercourse are not harmful during pregnancy. The foetus lies safely in the mother's womb and occasional movement, contact or orgasms cannot cause it any harm. During the action of orgasm, the womb will contract a little more than usual, but these aren't the same contractions as those just before delivery. But it should be kept in mind that there are no genital infection such as herpes or chlamydia.
However sex during pregnancy is not advisable if:
• If there's bleeding during pregnancy or after having intercourse it should always be reported to a doctor. An examination of the cervix and possibly an ultrasound scan will be suggested.
Once the baby arrives you may not be able to have sex too often, so better enjoy it while you can :) Just be gentle and nice :)