Review Question - QID 110030

A 32-year-old woman presents to a fertility specialist for an evaluation of infertility. She and her husband have been having unprotected sex 3-5 times per week for the past 15 months. The patient is a vegan and takes multiple vitamin supplements. She has a history of severe acne treated with topical antibiotics. She also has a history of well-controlled asthma and uses an albuterol inhaler as needed. Her last menstrual period was 3 weeks ago and was normal. Her periods are normally 30 days apart and last 3-4 days. She has never taken contraceptives. Her husband accompanies her at the visit and has not undergone an infertility workup. Her temperature is 98.6°F (37°C), blood pressure is 115/65 mmHg, pulse is 84/min, and respirations are 18/min. On exam, she is a healthy-appearing female in no acute distress. A complete blood count and basic metabolic panel are normal. Follicle-stimulating hormone and luteinizing hormone levels are within normal ranges. A hysterosalpingogram is performed and results are shown in Figure A. Which of the following is the most likely cause of infertility?