gynecologist

The odd thing is that I've never heard of an "andrologist", which would be the male equivalent. Men with problems in their genitals (like an enlarged prostate) have to go to a urologist.

More precisely, a gynecologist (spelt "gynaecologist" in British English) specializes in the female reproductive system.

A study of male medical specialists of various fields showed that self-reported sexual satisfaction with their wives were lowest amongst gynecologists. The ensuing speculation came to the conclusion that:
i) if your sex drive doesn't matter, become a gynecologist
and
ii) familiarity breeds contempt.