Tmi for some * Pelvic pressure after sex

мя

Having a bit of a naff time with discomfort after sex, it only seems to be positions which involve my legs being apart ie cowgirl or missionary (spooning or doggy is fine). It's a bearing down pressure feeling that radiates down my inner thighs. It's not coming from my vagina or uterus but more the muscles around the tops of my inner thighs beside my vagina/bum? Has anyone suffered with this? My consultant reckons its just normal pregnancy related but this is my 4th baby and I've never had anything like this. Do I stop having sex? Is there exercises or stretches I can do. I'm only 21+3. The pain lasts for anywhere up to 12 hours after sex then it's gone. If I sleep after sex it doesn't happen which I presume is because I'm relaxed. It's also eased / stops by sitting on something soft or laying down