Relationship between the Development of Secondary Infertility in Women of Reproductive Age with Copper vs Hormonal Intrauterine Devices

Abstract

Background: The relationship between previous IUD use and secondary infertility remains controversial, particularly in developing countries where reproductive tract infections and contraceptive practices vary.
Aim: To investigate the association between previous use of Cu-IUDs and LNG-IUDs and secondary infertility among reproductive-age women.
Patients and Methods: This hospital-based case-control study was conducted at the Department of Obstetrics and Gynecology, Tikrit Teaching Hospital, Iraq, between October 2025 and June 2026. A total of 120 women aged 20–45 years were enrolled and allocated into three equal groups: women with secondary infertility following previous Cu-IUD use (n=40), women with secondary infertility following previous LNG-IUD use (n=40), and fertile women with previous IUD use serving as controls (n=40).
Results: The duration of marriage was significantly longer among women with secondary infertility than controls (P=0.021). Previous miscarriage was more frequent in infertile women (P=0.046), while parity was significantly lower (P=0.018). Women with previous Cu-IUD use had a longer duration of IUD use than LNG-IUD users (4.8±2.1 vs. 3.6±1.8 years, P=0.011). Imaging demonstrated significantly higher rates of tubal abnormalities among previous Cu-IUD users than LNG-IUD users (P=0.041), although IUD type was not independently associated with secondary infertility after adjustment for confounders.
Conclusion: Previous use of modern Cu-IUDs or LNG-IUDs was not independently associated with secondary infertility. Instead, prolonged IUD use, previous pelvic inflammatory disease, and delayed attempts to conceive after IUD removal were the principal factors associated with secondary infertility.