@SuperSara
I'm having visions of some MNers reluctantly raising their overly long nightdresses above their knees once in a blue then laying back and thinking of England while they allow their long-suffering partner to have his wicked way for a few minutes.
LOL projecting much?!
This is actually YOU isn't it? 
Just because many posters think it's grim for a pregnant woman to be shagging a man who is NOT the baby's father, you assume they are prudish, and staid and boring in the bedroom.
Do grow up FFS. You sound ridiculous, and LOL at the irony! Having a go at people slagging off the OP... But then judging people who think fucking a man when you are pregnant (who is not the baby's father,) is gross and weird and wrong, by saying they MUST be boring in bed, old frumpy hags, getting dressed in the dark, wearing long nighties. What a hypocrite you are. 
All your silly, childish, petulant insults and finger-wagging ain't gonna make anyone change their mind.
So keep ranting and poking and dishing out insults. Says more about you DEAR. 
And as I said before, any man who wants to shag a woman who is pregnant with another man's baby, clearly has some weird fetish. No man I know would EVER want to do that. It's weird as fuck. End of.
@ReanimatedSGB
You know, a man who doesn't want to have sex with his pregnant partner might be a misogynist, or have some issues which mean the relationship needs to be binned sooner rather than later?
I know we are all entitled to our own preferences, and no one should ever have sex they don't want to have and all that, but if a man is actively repulsed by his partner's pregnant body, or thinks there is something 'wrong' with her for wanting sex, then that man has unhealthy views about sex and about women.
FGS, no-one has said ANYTHING about a woman having sex when she is pregnant with the man who is the father to her baby! But shagging a man who is NOT the father of your baby is grim.