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Ovulation clues you can use

Trying each month to pinpoint the day your ovaries will release an egg can be like trying to hit a moving target. After all, ovulation can occur any time from 10 to 17 days into your monthly cycle—and the day itself is not always the same, month to month.

What’s more, although sperm can survive up to 72 hours in a woman’s reproductive tract, an egg can be fertilized for just 12 to 24 hours after it’s released. That really narrows the window of opportunity for couples trying to conceive. Experts believe this “window” opens just two or three days before ovulation and shuts on the day the egg is released into the fallopian tube.

Telling time correctly

Fortunately, you can minimize the guesswork with methods that can help you see patterns in your menstrual cycle. (Doctors say you’ll maximize your chances of conception by having intercourse several times during the four days before the day you ovulate).

Ovulation-prediction kits. These over-the-counter tests look for a surge in luteinizing hormone (LH) in your urine. LH is released by the pituitary gland during your cycle; when LH levels peak, it triggers ovulation. Mayo Clinic has determined the kits are 97 percent accurate in predicting ovulation within 72 hours, giving prospective parents up to 48 hours’ notice that ovulation is imminent.

Basal body temperature. In BBT, you chart your temperature for several months to find a pattern to your ovulation. Buy a special BBT thermometer—it only measures up to 100°F and is easier to read accurately. Start taking your temperature each morning before you get up. It will normally be slightly higher right after ovulation. An increase of 0.4°F to 0.8°F at least three days in a row indicates ovulation has occurred. After several months you should know on which days ovulation can be expected.

Mucous secretions. Vaginal discharges change in quantity and type around the time of ovulation. A few days before, secretions will increase, signaling the beginning of your fertile period. On ovulation day, you may have a colorless slippery discharge instead of the cloudy, thicker secretions that come at other times of the month. Also note the first day you feel an increase in secretions and the day you feel the most discharge.

Mittelschmerz. In German, mittelschmerz means midcycle pain. About one in five women actually feels a distinct pain in the right or left ovary before, during or after ovulation. The pain lasts from a few minutes to 24 hours. Dark red or brownish spotting may also occur. Women experiencing mittelschmerz should note the day and use the information as another tool to predict ovulation.