Uterine Artery Doppler Indices: Pulsatility Index and Resistance Index as Predictive Tools to Menstrual Changes Related to Levonorgestrel Intrauterine System versus Copper Intrauterine Contraceptive Device Among Egyptian Women: A Cohort Study
Objective. This study aims to assess the predictive value of the uterine artery Doppler indices (pulsatility and resistance) using transvaginal ultrasound following the insertion of an intrauterine device (IUD), either the levonorgestrel intrauterine system (LNG-IUS) or the Cu-IUD and to correlate the findings of the impedance indices to the changes in the menstrual pattern.
Materials and Methods. A prospective cohort study was conducted between March 2019 and March 2021 that included healthy women who visited our family planning clinic and were willing to use an intrauterine contraceptive device. Of the 365 women who initially opted for this contraceptive method, 340 were enrolled. The participants were divided into two groups: (LNG-IUS) group, LNG-IUS users; (Cu-IUD) group, Cu-IUD users. The decision was made based on the women’s clinical circumstances and preferences. Then, the transvaginal ultrasonographic examination was performed after the deployment of the IUD and at three- and six-month follow-up intervals. Measurement tools included uterine Doppler impedance indices, and changes in the menstrual patterns were examined serially and recorded.
Results. The analysis showed a significant difference between the two groups. Women in (LNG-IUS) group experienced irregular vaginal bleeding at a rate of 28.2% compared to 35.2% in (Cu-IUD) group (P = 0.001), and amenorrhea was statistically reported at a rate of 67.7% in (LNG-IUS) group compared to 7.05% in (Cu-IUD) group at the end of the study (P = 0.001). The uterine artery pulsatility index (PI) was significantly associated with abnormal bleeding at a cut-off of 1.29 with an area under the curve (AUC) of 0.92, a sensitivity of 89%, and a specificity of 100%. In contrast, uterine artery resistance index (RI) was significantly correlated with abnormal bleeding at a cut-off of 0.61 with an AUC of 0.11, a sensitivity of 95%, and a specificity of 100%.
Conclusions. Our results confirmed our assumption that the LNG-IUS, a hormonal contraceptive device unlike the Cu-IUD, significantly altered the blood flow of the uterine artery and menstrual pattern.