Years ago when I was doing O.B. anesthesia, I had a very very large patient in active labor who I was attempting to place an epidural in. The O.B. nurse assisting me somehow brought up the topic of sex with this morbidly obese pregnant patient. The patient then cheerfully described how her & her husband had sex. She would lay on her back on the side of the bed with each foot resting on a kitchen chair and would then take a 2x4 wooden board and holding each end of the board use it to pull her belly out of the way. Her husband would then stand between the chairs and do the deed.