The general odds of getting pregnant during ovulation are calculated by considering a woman's age, frequency of sexual intercourse and the number of months a couple has been trying, according to WebMD. For most couples trying to have a baby, the odds are approximately 15 to 25 percent that a woman conceives in a specific month.
The odds drop for women older than 30 to get pregnant, and the chances decrease significantly once a woman reaches her 40s, WebMD reports. The more often a couple engages in sexual intercourse, the more likely the woman becomes pregnant. Couples trying to conceive should have sex often because the chances of an egg becoming fertilized are so small, WebMD notes. The time window during which a woman becomes pregnant only includes four or five days before ovulation and the day of ovulation. Chances of pregnancy are highest on the day before and the day of ovulation.
Couples still attempting a pregnancy after one year of being unsuccessful have a lower chance, according to WebMD. In addition, irregular menstrual cycles also affect a woman's overall chances of getting pregnant because she could be ovulating less frequently. Understanding the details of the menstrual cycle helps couples conceive more quickly. Women's cycles begin on the day they notice blood that is bright red, and a cycle typically lasts from 21 to 35 days. A cycle ends on the day the next cycle starts.