How can I tell when I’m going through my fertile period?
The fertile period is the time during your menstrual cycle where pregnancy is possible.
Every month, your ovaries mature (usually) one egg and release it, hoping to be met by a sperm. The act of egg release is known as ovulation. The egg usually survives for about 24 hours after ovulation. You usually ovulate 14 days before your next period. Therefore, if you have a 28-day cycle, ovulation usually happens on day 14, and day 16 for a 30-day cycle, and so on.
Many women don’t know when they ovulate. Some women may experience some pain from the follicle rupture. Body temperature rises slightly with ovulation, so some women do basal body temperature (BBT) charting. Cervical mucus becomes clearer and thinner in consistency.
An ovulation prediction kit (OPK) detects an increase in a hormone called Luteinizing Hormone or LH. The LH surge occurs about 24 to 36 hours before ovulation. Therefore, if the test kit is positive, you should ovulate within 24 to 36 hours. The cost of ovulation prediction kits can be high.
The fertile period starts five days before ovulation, but the best time to attempt intercourse for conception is from two days before ovulation up until the day of ovulation.
Timed intercourse (around the time of ovulation) has not been shown to be better than untimed intercourse when couples are trying to conceive. Possible reasons are the added stress from all the various methods of determining ovulation, the increased cost, and the husbands’ inability to perform on demand. We call this “tonight’s the night syndrome”. In fact, in one study of women trying to conceive, researchers found that while 68 per cent indicated that they were practicing timed intercourse, only 13 per cent could correctly identify their fertile period!
Professional bodies such as the Royal College of Obstetricians and Gynaecologists (RCOG) in London, therefore, advise that the optimum frequency of unprotected sexual intercourse in couples trying to conceive is two to three times per week, regardless of the menstrual cycle. Sperm can survive in the vagina for at least two to three days, and as mentioned already, the egg only survives for about 24 hours after ovulation. Methods to predict ovulation, such as BBT charting, and OPK use, are not recommended.
Question answered by:
Dr Lim Min Yu
NUH Women’s Centre