Vitamins, Minerals, and Preconception Health

SEPTEMBER 18, 2017
Jeannette Y. Wick, RPh, MBA, FASCP
For decades, health care professionals have known that neural tube defects at birth are often associated with insufficient prenatal folic acid intake. For that reason, public health officials urge pregnant women to take prenatal vitamins that contain a sufficient amount of folic acid as soon as they realize that they are pregnant.

A study published in the American Journal of Obstetrics and Gynecology examined the influence of diet and intake of vitamins and minerals on fertility. Assembled by 2 researchers from Brigham and Women's Hospital and Harvard Medical School in Boston Massachusetts, this article is a comprehensive review of diet and human fertility with a focus on impaired fecundity.

Of note, the authors reported that supplemental folic acid, in addition to decreasing the incidence of neural tube defects, is also associated with greater fertility in general, as well as decreased risk of miscarriage and greater success in women who seek infertility treatment. Although the authors do not recommend a specific dose level, they indicated that doses used often exceed those currently recommended for prevention of neural tube defects.

Previously, researchers have had tremendous interest in vitamin D based on promising evidence from animal models, the authors noted. However, current research indicates that in humans, vitamin D seems to have little influence on fertility unless the woman has a vitamin D deficit. Research findings are mixed on this topic.

The authors indicated that antioxidant supplementation seems to positively influence the success rate associated with infertility treatments if the male partner is supplemented. At this time, it's unclear which oxidants or doses are preferable.

Women who took long chain omega 3 fatty acids seemed to be more fertile than others. The authors noted that often, foods containing long chain omega-3 fatty acids are contaminated with environmental toxicants, which confounds interpretation of results and may reduce the benefit.

Here, as in so many other conditions, healthy diets rich in seafood, poultry, whole grains, fruits, and vegetables appeared to improve women's fertility and semen quality in men.

Soy and soy supplements also appeared to have a beneficial effect in women who undergo infertility treatments, although previous data indicated they did not.

This summary provides excellent information for pharmacists who work with patients who have difficulty becoming pregnant; 15 to 25% of couples in the United States experience fertility problems. Understanding interventions that improve the likelihood of successful pregnancy naturally or with reproductive assistance can help couples avoid the emotional and financial burden of fertility treatments.

Gaskins AJ, Chavarro JE. Diet and Fertility: A Review. Am J Obstet Gynecol. 2017 Aug 24. pii: S0002-9378(17)30945-6. doi: 10.1016/j.ajog.2017.08.010. [Epub ahead of print]