The role of diet in unexpected poor response to ovarian stimulation: a cross-sectional study

Research question: Is there an association between diet and poor ovarian response to ovarian stimulation in women with normal biomarkers of ovarian reserve? Design: Women eligible for IVF at an Academic Fertility Center were invited to participate in this prospective cross-sectional study. The main inclusion criteria were age 18–39 years, body mass index 18–25 kg/m², preserved ovarian reserve (antral follicle count 10–22 or anti-Müllerian hormone concentration 2–5 ng/ml) and a starting dose of gonadotrophins of 150–225 IU/day. Information on diet was obtained using a validated food frequency questionnaire. ‘Unexpected poor ovarian response’ was defined as the retrieval of three or fewer suitable oocytes. A logistic regression model was used to adjust for confounders. Results: Out of the 303 women enrolled in the study, 48 (16%) showed an unexpected poor ovarian response. The frequency of poor responders increased with increasing glycaemic load, carbohydrate intake and fibre intake. When comparing the third with the first tertile (reference), the adjusted odds ratios for these were 3.91 (95% confidence interval [CI] 1.11–13.83, P = 0.04), 4.78 (95% CI 1.23–18.51, P = 0.02) and 6.03 (95% CI 1.18–30.77, P = 0.07), respectively. Conclusions: Elevated dietary glycaemic load as well as carbohydrate intake and fibre intake is significantly associated with unexpected poor ovarian response. Future interventional studies should clarify whether dietary modification might restore normal response.