Sex on Doctor's Orders

Tom was pretty low on the hospital's totem pole, but he had what all the doctors wanted: Beth, his curvaceous, over-sexed wife. This didn't bother Tom. He knew from experience there was more than enough to go around. Then Dr. Beresford arrived to start some rather interesting experiments with male volunteers, some of whom needed a little help to produce. It was only logical he'd hire Beth to give it to them.
Then things started to get out of hand... Or was it in hand? Beth was so excited she was never quite sure.