To the Editor.
—Dr Hankinson and colleagues1 report an inverse relationship between tubal ligation and ovarian cancer and propose mechanisms for a possible causal association that involve altered ovulatory cycles and gonadotropin, estrogen, and progesterone levels. They conclude that it "may be appropriate to consider the reduced risk of ovarian cancer when choosing among alternative methods of contraception." Their findings, which corroborate several studies, are interesting and important. However, it is imperative to question how tubal ligation may alter normal physiology of premenopausal women and what long-term effects it may have on accelerating two conditions which eventually occur in virtually all women, osteoporosis and atherosclerosis. In this context, the effects of ovulation and estrogen and progesterone levels on bone density and lipid levels should be considered.Concerning bone density, it has been shown that even asymptomatic ovulatory disturbances may be associated with decreased spinal density.2 With regard to
Whitmore SE. Tubal Ligation, Hysterectomy, and Risk of Ovarian Cancer. JAMA. 1994;271(16):1236. doi:10.1001/jama.1994.03510400021013