While sperm can survive for three of four days inside a woman, it only takes the egg between 12 and 24 hours to make its way through the fallopian tube after ovulation. The best chance of conception comes when a couple have intercourse one to two days before ovulation.
A woman typically ovulates 14 days before her period. If a woman has a regular cycle length of 28 days, she will ovulate mid-cycle - 14 days after day one of her period. If the cycle is longer, say 34 days, ovulation occurs around 20 days after day one of a period - not mid-cycle. Using this calculation will tell you when the best chance of conception will be.
Some women know when they are ovulating from changes in their body and the way they feel. Some typical indicators are breast soreness, heavier and more opaque vaginal discharge, tightness in the abdomen. Many others have no noticeable symptoms.
Basal body temperature (BBT)
Two days after ovulation, your temperature rises slightly. While this is not useful for that particular cycle, taking your temperature every morning before you get out of bed is an easy way to chart your cycle. Track the rises in BBT for a few months to work out how regular your cycle is and use this to predict the date of your ovulation.
If your tracking indicates that your cycle is irregular, try counting back 11 days from your longest cycle and 17 days from your shortest cycle. The days in between will be your most fertile.
Knowing that sperm can survive inside a woman for a number of days, if a couple is having regular sex (two to three times a week) there is a good chance that there will be some sperm there to meet your egg when it arrives.
It is a myth that men should "store" their sperm by abstaining from sex. Long periods of abstinence can lead to a decrease in sperm quality. Our best advice is to have sex two or three times a week, no matter where a woman is in her cycle.