Does eating more whole grains improve pregnancy rates?

This study explored whether whole grain intake before in vitro fertilization improved pregnancy rates. The results showed that a higher intake of whole grains before IVF resulted in higher pregnancy rates.

Whole grains are very high in nutrients such as vitamins and fiber. They are thought to help reduce the risk of some diseases, including heart disease and diabetes. Whole grains may have a positive effect on fertility. Infertility is associated with inflammation (an immune response) in the body, and whole grains contain substances that reduce inflammation. Whole grains are also known to regulate blood sugar levels, which can be associated with polycystic ovary syndrome (PCOS, a cause of infertility due to hormone imbalances). The effects of whole grains on pregnancy outcomes is unclear.

This study examined the association between whole grain intake prior to IVF (a fertility treatment where an egg is fertilized by sperm outside the body and then implanted into the woman’s uterus) and pregnancy rates. 273 patients completed food questionnaires reporting the foods they had eaten and how often they had eaten them over the previous year.

Average whole grain intake was 34.2 g per day (about one/two servings). Higher intakes of whole grains resulted in higher birth rates. Success in getting pregnant through IVF was 53% for those consuming over 52.4 g per day of whole grains, compared with 35% success rate for those consuming less than 21.4 g per day. Bran was associated with a better result.

A 28 g per day increase in whole grain intake was associated with an increase in endometrial thickness (the thickness of the internal layer lining the uterus).

Patients with higher whole grain intakes tended to have a healthier diet, with more fish, fruits, vegetables, nuts and beans, and less red meat, processed meat, butter, refined grains, and sweets.

The study concluded that there was an association between whole grain intake and pregnancy rates, and highlighted the importance of diet when trying to conceive. The increase may be related to increased endometrial thickness.

The food frequency questionnaire can contain errors.