Return rate following a live birth obtained with ART: frequency and determinants

Purpose: To understand how often couples return to ART centres for a second child. Methods: Retrospective monocentric cohort study including women who had a first live birth with IVF. The primary objective was to assess the rate of those returning for a second child within five years of the previous pregnancy. The secondary aim was to disentangle the determinants of this rate. Results: A total of 374 patients were included, of whom 188 returned (50%, 95% CI 45–55%). Among those who did not return (n = 186), four (2%) referred to another ART Center and 24 were unreachable. Of the 158 contacted subjects that did not refer for ART, 53 (34%, 95% CI 27–41%) conceived naturally, 57 (36%, 95% CI 29–44%) abandoned their intent of parenthood, and 48 (30%, 95% CI 24–38%) unsuccessfully attempted natural conception. These 48 women (13%) who expressed interest in a second child but did not undergo ART were compared to those seeking a second pregnancy through ART. Baseline characteristics were similar except for an older age (Median 36, IQR: 34–38 vs 34, IQR: 32–36, p = 0.001). Additionally, in terms of IVF cycle characteristics, women who did not return were more likely to achieve their first pregnancy with a fresh transfer rather than a frozen transfer (75% vs 59%, p = 0.05). They also had a higher number of retrieved oocytes (Median 10, IQR: 7–13 vs 9, IQR: 5–12) and less frequently cryopreserved embryos (27% vs 52%, p = 0.003). Conclusion: The proportion of couples who have conceived with ART and who are interested in having a second child is high. Our results underline the importance of paying more attention to the number of intended children, as this information could influence clinical management.