Iron intake and risk of ovulatory infertility

Obstet Gynecol. 2006 Nov;108(5):1145-52. doi: 10.1097/01.AOG.0000238333.37423.ab.


Objective: To evaluate whether iron supplement use or greater intake of total, heme and nonheme iron is associated with lower risk of ovulatory infertility.

Methods: We conducted a prospective cohort study among 18,555 married, premenopausal women without a history of infertility who attempted a pregnancy or became pregnant between 1991 and 1999 (mean baseline age+/-standard deviation 32.6+/-3.6). Diet was assessed twice during follow-up and prospectively related to the incidence of infertility due to ovulatory disorder.

Results: During the 8 years of follow-up, 438 women reported infertility due to ovulatory disorder. Women who consumed iron supplements had a significantly lower risk of ovulatory infertility than women who did not use iron supplements (relative risk 0.60, 95% confidence interval 0.39-0.92), after adjusting for potential confounders. Total nonheme iron intake, primarily consumed as multivitamins and iron supplements, was inversely associated with the risk of infertility (relative risk Quintile 1 compared with 5, 95% confidence interval 0.39-0.92; P, trend .005.) Heme iron intake was unrelated to ovulatory infertility in multivariable adjusted analyses.

Conclusion: Consumption of iron supplements and nonheme iron from other sources may decrease the risk of ovulatory infertility.

Level of evidence: II-2.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Cohort Studies
  • Dietary Supplements
  • Dose-Response Relationship, Drug
  • Female
  • Humans
  • Infertility, Female / etiology
  • Infertility, Female / prevention & control*
  • Iron / administration & dosage*
  • Iron / pharmacology
  • Multivariate Analysis
  • Ovulation / drug effects*
  • Premenopause
  • Risk


  • Iron