Yes. Women are usually most fertile during the middle part of their cycle. This is usually about 12 to 14 days after the start of a period and sperm can live up to seven days inside the body. However, your monthly cycle can change without you realising it. If you’re thinking about using your monthly cycle as a birth control method, you should seek natural family planning advice from a health professional like your sexual health service, CASH/contraception clinic or GP.