I agree with Kazbah. Your body would benefit from some of the same hormones that course through your body when having satisfying sex. But bear with me: It's a brain thing you're after.... not just a physical. It's not just about semen making contact with your cervix... it's the sense of being safe, being loved, feeling secure that having good quality sex gives you. Just having sex for the sake of it won't cut it... infact if it makes you tense up and mentally uncomfortable then i'd go as far as to say it would stall things even longer.

To go into labour you have to feel safe and content. Do whatever it takes to get your mind into that place. It sounds like sex isn't going to get you there so don't go there! We are like any other member of the animal kingdom... think about cats who go in search of dark, quiet, enclosed safe places before having their litter. Animals who feel under attack (which the pressure of having sex can make you feel! LOL) stall labour until they are safe... often for days. tell this to your DH. If he wants this baby to arrive then he has to make you feel safe and protected... not the source of pleasure at your sufferance!