to the editor: I read with great interest the article, “Infertility,” in American Family Physician.¹ Although the information was extensive and well referenced, I would like to make three additional points about the current understanding and treatment of infertility.

My first point is the importance of highlighting the two categories of infertility. Primary infertility is the failure to achieve pregnancy during one year of frequent, unprotected intercourse. Secondary infertility is defined as couples who have previously been pregnant at least once, but have been unable to achieve another pregnancy.²

Epidemiologic studies indicate cigarette smoking, abnormal body mass index, and excessive caffeine and alcohol consumption reduce fertility in the female partner.³ Couples with unexplained infertility should be informed of a possible relationship between cigarette smoking and infertility and advised to stop smoking.³ The female partner should be counseled to try to achieve a body mass index between 20 and 27 kg per m², reduce caffeine intake to no more than 250 mg daily, and reduce alcohol intake to no more than four drinks per week. These changes may enhance natural and assisted conception.⁴

My last point is the therapeutic role of tubal flushing. Several studies have reported increased pregnancy rates after diagnostic hysterosalpingography.⁵ A Cochrane review of 11 randomized trials found that tubal flushing with oil-soluble media versus no intervention was associated with a significant increase in pregnancy rate (odds ratio = 3.30; 95% confidence interval, 2.00 to 5.43).^5–6

editor's note: This letter was sent to the authors of “Infertility,” who declined to reply.