Murph - there isn't any real reason to NOT DTD unless you've been advised by your doctors due to recurrent miscarriage issues. the cervix forms a protective plug, and unless you're having very hard/violent sex your embryo is going to be very well protected in there. the cervix has a larger volume of blood pumping through it (everything down there does!) so you can sometimes bruise and the bruises will actually bleed kwim?

i've not abstained during the pg, as petrified as i was a the start - i just wanted to feel normal after everything we've been through - we just made sure to be a little bit more careful to make sure not to go at things too hard - DH was really good and if i say to be gentle, he changes what is happening so as not to make me uncomfy.

FWIW - i've heard that orgasm causes the uterus to contract a little and give the baby a "cuddle" - so i think we're just teaching our gremlin about affection from a really young age!! and the increased blood flow means O is more intense most of the time so it's the most enjoyable time to dtd!