Around two weeks after a woman’s menstrual period begins, a mature egg is released from the ovary and becomes available for fertilization. This phenomenon is called ovulation. If the couple has sexual intercourse during this time without any birth control, it is likely that the sperm fertilizes the egg and conception occurs. Sperm cells can live for two or three days, but an egg survives no more than 24 hours after ovulation if fertilization does not occur. To get pregnant, you should have sexual intercourse during the period spanning one to two days before ovulation to about 24 hours afterward.
The good news is that there are ways to determine the ovulation period quite satisfactorily. There is a simple calculation count back 12 to 16 days from when your next period is due. This gives you a range of days when you will probably be ovulating. If you have a 28-day cycle, the 14th day is often the day of ovulation. But this method is very unreliable, especially if you have irregular periods. There are other methods like noting your basal body temperature or noticing your cervical mucus but they could be tricky.
An ovulation kit is a better option. It determines your date of ovulation a day in advance by detecting levels of a hormone (luteinizing hormone) which hits its peak in the middle of your menstrual cycle. Using an ovulation kit is pretty easy, convenient and detects the ovulation period right almost 97% of the time. You can buy them from any chemist’s shop or online.