The only time mine was uncomfortable was about 3 weeks ago so i was about 31 wks and I stopped in the middle and ran to the bathroom bc it hurt so bad. Turns out I got a huge varicose vein on my vulva. Extremely uncomfortable. It feels like you have a huge cut on your vag and stings like crazy. My ob said he's never seen one on the vulva never not go away after pregnancy-so that's good! If you have a varicose vein try to stay off of your feet as much as possible and don't sit with your legs crossed bc it cuts circulation off to that vein which can cause it to swell even more. But if not a vein-definitely try lube! Depends on what's uncomfortable. Dryness or laying on your back or side
Oh yes and sometimes its painful. Just grab some lube and lather her up. Should help some. :)
Sorry i dont have advice but just kno ur not the only one im 33 weeks & been having uncomfortable sex since 16 weeks !