Influence of Maternal Age and Ovarian Reserve on the Decision to Continue or to Cancel IVF Cycles in Patients with One or Two Large Follicles: a Dual Effect

This study aimed to study whether IVF stimulation that results in one or two mature follicles should proceed to oocyte retrieval. This is a retrospective cohort study conducted at McGill University Health Center on 459 patients who underwent IVF treatment between 2011 and 2014, undergoing hormonal stimulation and monitoring of their ovarian response. The primary outcomes were pregnancy and live birth rates. Statistical modeling was used to determine individual roles of patient age and ovarian reserve on outcomes, while controlling for the other factors. Of the 459 cycles included in the study, 360 cycles (78.4%) ended in embryo transfer. Live birth rates per cycle were 15.6%, for the ≤ 34-year-olds; 6.5%, for the 35–39-year-olds; and 2.7%, for the ≥ 40-year-olds (p < 0.01). Twenty-five percent of the cycles in the ≥ 40-year-old group were canceled versus 17% and 15% in the 35–39-year-old and ≤ 34-year-old groups, respectively (p < 0.05). Testing likelihood of live birth as a function of age and antral follicular count (AFC) revealed that a 1-year increase in age reduces the likelihood of live birth by 11% (p < 0.05) and one-unit increase in AFC count leads to a 9% increase in the odds of a live birth (p < 0.05). For the youngest age group, the AFC had a most significant effect, and those with AFC > 11 had 56% live birth rate, while those with AFC ≤ 11 had only 6% of live birth rate. This study supports a shift in reasoning from age being the predictor of outcomes in women with a low response at IVF to both age and ovarian reserve needing to be taken into consideration.