Maybe IUD but to me it sounds like a combination of busy life and attempting to have sex late at night. Make a lunch date or take advantage of the times when the little one is napping or on a play date. Make time for you. Don't let your sex life, and all of the wonderful family building that goes along with it, be an afterthought. Sometimes it's hard, but don't let an opportunity for a great love making session get pushed aside because there is laundry to do.

Almost forgot, the best aphrodisiac for a woman is an understanding man. A guy can get excited and cum at 4am in the back seat of a mini cooper stuck on a rail road crossing while he's late for a job interview.

Personally, my wife gets turned on when I bring home lunch and vacuum so she can relax and eat it.

Good luck!