Subfertility and gastrointestinal disease: 'unexplained' is often undiagnosed

Subfertility can be more reliably explained and effectively treated with an improved understanding of the contribution of chronic medical disease to reproductive dysfunction. This review addresses several common gastrointestinal disorders which are increasingly implicated in infertility and early pregnancy loss: celiac disease, inflammatory bowel disease (ulcerative colitis and Crohn's disease), and hemochromatosis. Appreciating the reproductive impact of these comorbidities and their treatments enables clinicians to accurately counsel patients and to modify medical and fertility treatments based on etiology. Because unexplained infertility can represent the initial presentation of undiagnosed medical disease, considering these often-subclinical gastrointestinal disorders in the differential diagnosis of subfertility provides an opportunity not only to increase the probability of conception and uncomplicated pregnancy, but also to improve overall maternal health.