The woman has to be ovulating. If she had her period two weeks ago, then there is a good chance that she will conceive on the first try. If she was taking the Birth Control Pill for over six months, then her hormone levels will probably need some time to adjust, which makes it difficult to conceive right away. In your case, you really have no choice, if you are healthy and have a normal sperm count. One way to avoid having a low sperm count is to avoid smoking marijuana and avoid wearing tight underwear (the tight underwear will bring the testicles closer to the body and cause the sperm to overheat, which reduces the sperm count).