Dr. Lippes and his loop. Four decades in perspective
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Updated: Oct 18, 2026

Studying DNA Looping by Single-Molecule FRET
Published on: June 28, 2014
1Department of Obstetrics and Gynecology, United States Naval Hospital, Bremerton, Washington, USA. rusthomsen@aol.com
Abstract:
Forty years ago Jack Lippes, M.D., hand made the first models of his "Double-S" intrauterine contraceptive device (IUD). Subsequently the Lippes Loop became the standard against which other IUDs came to be compared. Though millions of loops have been used, they have mostly been supplanted by copper-bearing, T-shaped devices. Due to the implant nature of IUDs, on occasion a patient presents well into menopause still bearing a Lippes Loop or other early IUD. Although there is no established causal evidence linking IUDs retained after menopause and cancer or other significant problems, such retention does confuse the diagnosis of post-menopausal bleeding and makes difficult such procedures as endometrial biopsy and ultrasonic endometrial evaluation. When contraception is no longer an issue, it is prudent to remove IUDs since they may cloud future necessary evaluations.
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