Brenda is pregnant with her first child and is paying a visit to the prenatal clinic with her doctor. When the examination was complete, Brenda shyly and awkwardly began "Erm. My husband wants me to, erm, ask you."
"I know, I know." said the Doctor with a warm and knowing smile. Placing a reassuring hand on her shoulder he said "I get asked this question all the time and yes, sex is fine until late in the pregnancy so long as you lay on your side, or use what some people refer to as the doggy position."
"No, no Doctor. It's nothing to do with that." Brenda confessed. "He wants to know if I can still mow the friggin' lawn!"