For the study, Chavarro and colleagues used data from a large study of 18,000 registered nurses between the ages of 24 and 42. Over the course of 8 years, the researchers noted that there were over 3,500 cases of infertility among the women involved. Of those who went for further testing to find the source of their infertility, 438 women found they were having difficulty becoming pregnant because of an ovulatory disorder, meaning their body had trouble producing viable eggs.
Looking at the iron intake of these women, the researchers found that those women who used iron supplements had about a 40 percent lower risk of having an ovulatory disorder. In fact, women who took supplements with high iron content—more than 41 milligrams a day—lowered their risk of an ovulatory problem by 70 percent.
However, the connection between iron and fertility is not totally clear. “Some researchers have suggested that iron may be important for ovulation as the egg has an increased demand for iron while it matures,” said Chavarro.
Chavarro warns that this study is preliminary and more work needs to be done before the link between some cases of infertility and iron intake is completely established. However, “given that iron deficiency is commonly found among women of reproductive age,” he writes in Obstetrics and Gynecology, “women planning to become pregnant should consider using iron supplements because they may help them prevent iron deficiency and also improve fertility.”
