You probably already know quite a lot about your menstrual cycle – like how often you get your periods and how heavy they are. Women’s cycle lengths vary and and can be calculated by beginning with the first day of the last period. Most females ovulate anywhere between Day 11 – Day 21 of their pattern, but some females may have a shorter or longer interval.
When you are ovulating you are most fertile. Lovemaking during this time improves the possibility of maternity. Ovulation can happen at various times during a cycle, and may happen on a different day each 30 days. It is essential to monitor your cycle; there are resources online to help you do this.
Most likely if you never miss your birth control pills and you always take them at about the exact same time everyday then you don't have to worry about getting pregnant. That is what birth control is for after all. So as long as you are committed to taking it properly you have very little to worry about.
If you are still worried, tracking your cycle and using a "back up" method during your most fertile time will give you the added peace of mind that your require. You and your partner have many options so have fun in choosing.
An added note of caution is that you do not have a regular partner, or if you feel you cannot trust your current regular partner to not have sex with other partners, please also protect yourself against diseases by using condoms every time you have sex.
If you and your partner are committed and monogamous than there are a variety of products and methods to help you avoid becoming parents before you are ready. There is everything from female condoms to the rhythm method to give you the added peace of mind that you will not get pregnant while you are ovulating even though you are on the pill.
Remember, commit to taking your pill at the same time everyday and you are already on track to not becoming a mom before you are ready.