NEW YORK (Reuters Health) - The use of iron supplements may reduce a woman's risk of ovulatory infertility, according to a report in the current issue of Obstetrics and Gynecology.

The findings of a small study suggest that iron supplements may improve pregnancy rates in women with a history of infertility. In addition, studies in women with celiac disease provide supporting evidence that adequate iron stores promote fertility. However, until now, no study had looked at the effects of iron supplementation on pregnancy rates in apparently healthy women without a history of infertility.

Dr. Jorge E. Chavarro, from the Harvard School of Public Health in Boston, and colleagues analyzed diet information for 18,555 premenopausal women who became or attempted to become pregnant from 1991 to 1999.

During the 8 years of follow-up, ovulation-related infertility was reported in 438 women. Women who reported using iron supplements were 40 percent less likely to have ovulation-related infertility than nonusers, the report indicates.

With increases in total nonheme iron, the risk of infertility fell, the team found. By contrast, consumption of heme iron seemed to have no effects on fertility.

Heme and nonheme are the two types of iron derived from food. Foods such as meats and seafood provide heme iron, while nonheme iron is found in plant foods such as spinach.

"Given that iron deficiency is commonly found among women of reproductive age and may be associated with adverse pregnancy and infant outcomes, women planning to become pregnant should consider using iron supplements because they may help them prevent iron deficiency and also improve fertility," the authors conclude.