Women are born with seven million eggs, which is reduced to 400,000 at puberty. In a woman’s lifetime, approximately 400-500 eggs will ovulate. Ovarian reserve declines as a woman ages, with egg supply taking a rapid decline in the late 20s and again in the 30s, particularly after 35. Pregnancy rates in the early 30s are 15 percent, then decline to 10 percent after 35 and 5 percent over 40.