In vitro fertilization in women under 35: counseling should differ by age

The aim of this study is to evaluate the outcomes of in vitro fertilization (IVF), including cumulative live birth rate, among women <25 years, 25 to <30 years, and 30 to <35 years.

A retrospective cohort study of all women 18 to <35 years of age at their first fresh-embryo, non-donor IVF cycle from January 1995 through December 2012 at a single center was conducted. A competing-risk regression model was used to estimate the cumulative probability and 95 % confidence interval (CI) of the first live birth in up to 6 cycles during the study period with IVF cycle number as the time metric.

Among 7243 women who underwent 16,792 cycles, there were 163 (2.3 %) women <25 years, 1691 (23.3 %) women 25 to <30 years, and 5389 (74.4 %) women 30 to <35 years. Women <25 years had the lowest cumulative live birth rate after each cycle, followed by women 30 to <35 years. In both groups, the cumulative live birth rate after 6 cycles was significantly lower than that of women 25 to <30 years; these rates were 58 % (95 % CI 0.51-0.66) among women <25 years, 69 % (95 % CI 0.67-0.71) among women 25 to <30 years, and 64 % (95 % CI 0.63-0.65) among women 30 to <35 years.

Our findings are consistent with other reports of less favorable IVF treatment outcomes in women <25 years of age following their first IVF cycle. This indicates that there are underlying factors in couples with a female <25 years of age that should lead to different treatment counseling when they attempt IVF.