A 28-year-old woman presents with pan-ulcerative colitis since age 16 years. Her symptoms were previously well-controlled with vedolizumab and mesalamine, but she has recently begun to experience frequent flares of disease. She is interested in having children and is referred for consideration of elective surgery involving a restorative proctocolectomy with an ileal pouch–anal anastomosis. What is the postsurgical effect on future childbearing about which you would counsel the patient?