Women?s fertility begins to decline at age 27, not in their early 30s as was previously thought. As reported in Human Reproduction, women between the ages of 27 and 29 generally take 1 month or 2 longer to conceive than do younger women. The fertility rate shows little decline between the ages of 27 and 34 but then drops again at age 35. The study authors calculated the probability of becoming pregnant during the best time for conception?2 days before ovulation. Women aged 26 and younger had a 50% chance of conception, women aged 27 to 34 had a 40% chance, and women aged 35 to 39 had a less than 30% chance. The probability of conception among women aged 35 to 39 fell even lower (to 18%) if the woman?s partner was age 40.