Understanding your body is the first step to successful conception. Every woman is different and a normal menstrual cycle can be between 24 to 36 days. You ovulate only once each menstrual cycle, and there are just a few days during that time when it's possible to conceive. Plan to have sex during your most fertile days, which is usually about three days before ovulation. Better to have sex every other day during the fertile window. And healthy sperm is also important for fertilising the egg. The study says that alcohol, tobacco affects the sperm quality and subsequently reduce the chances of getting pregnant.