sex with pregnant girls is pretty much exactly the same as sex with non-pregnant girls. only later in the pregnancy, you have to be kind of inventive with positions. for some married couples, this is a problem if they've only have "missionary" sex previously.
also, some women have "lubrication issues" during pregnancy. of course, these can be easily resolved.
this may go without saying, but you really AREN'T "poking the kid in the head".
many women are horny as hamsters while pregnant. the thought of "not getting any for 9 months" is the exception, not the rule.
There ARE of course, situations where, for the good of the mom or the baby or both, the Dr will recommend no VAGINAL intercourse.
There ARE other kinds of sex, ya know...
