Reproductive outcomes after ileo-pouch anal anastomosis: clarifications and the importance of fertility counselling

Correspondence to: Anders Mark-Christensen (e-mail: andersmark@dadlnet.dk)

Department of Surgery

Odense University Hospital

J.B. Winsloews Vej 4

5000 Odense C

Denmark

BJS, https://doi.org/10.1093/bjs/znaf136, published 11 July 2025

We thank Schmidt et al. for their thoughtful comments on our recent article1. The authors appropriately underscore the important distinction between fertility and birth rates, a point with which we fully agree with. We wish to clarify that our manuscript was not intended to imply equivalence between these measures and we fully acknowledge that a range of social, demographic, psychological and economic factors can influence both the capacity and the decision to conceive, thereby impacting observed birth rates.

We chose to begin the observation period at restoration of bowel continuity rather than the rectal dissection (performed at the ileo-pouch anal anastomosis (IPAA) operation) to minimize the potential immortal time bias associated with the presence of an ileostomy.

We agree that prospective studies, such as the Women with Inflammatory Bowel Disease and Motherhood Study (WIsDoM), are essential to advance reproductive counselling for women with IBD. These designs allow for direct measurement of fertility and collection of detailed data on conception attempts, use of assisted reproductive technologies, disease activity, reproductive history, and detailed surgical technique — information not available in large-scale registry studies.

It is, however, important to recognize that the existing literature on fertility after IPAA is dominated by observational studies, limited by either small sample sizes2-4 or lack of information on measures of voluntary childlessness5. These studies are often cited as evidence of substantial fertility differences between surgical approaches and used to counsel women on fertility after IPAA

Our study reports on the highest number of births in an IPAA cohort to date, using nationwide data from 578 women of reproductive age undergoing IPAA between 2000 and 2022. While registry-based studies have inherent limitations, we sought to address key confounders; for example, use of oral contraceptives and assisted reproduction technology was similar between laparoscopic and open groups, making it unlikely that differences in the desire to have children accounted for the comparable birth rates observed. Importantly, our findings highlight the need to discuss potential reproductive implications and to offer fertility and pregnancy counselling when planning IPAA surgery. We therefore believe that our study adds substantially to the body of evidence that can be used in such counselling. We believe our findings provide a robust population-level perspective on reproductive outcomes after IPAA, while acknowlegding the need for complementary prospective studies to more precisely assess fertility.