Correlation between uterine artery Doppler indices and menstrual irregularities among levonorgestrel releasing intrauterine system and depot medroxyprogesterone acetate users: a prospective observational study.

OBJECTIVE: To ascertain whether menstrual irregularities among users of levonorgestrel releasing intrauterine system (LNG-IUS) and depot medroxyprogesterone acetate (DMPA), were associated with changes in uterine artery Doppler indices or not.

METHODS: This three-year prospective observational study included 102 women using LNG-IUS and 104 women using DMPA for contraception. Participants were followed at regular intervals over three years with performance of transvaginal ultrasound to measure uterine artery pulsatility index (PI) and resistance index (RI) before starting the method and at six months, 12 months, two and three years thereafter. Data was collected and tabulated.

RESULTS: Significant changes in uterine artery PI and RI were detected. PI indices were reduced after six months of use in both groups and elevated significantly at 12 months in both groups compared to initial values (p < .001) while RI significantly reduced after six months in both groups and elevated significantly at 12 months, two and three years in both groups compared to initial values (p < .001). Both PI and RI significantly reduced in women suffered abnormal uterine bleeding and significantly elevated in women experienced amenorrhea irrespective of the method used (p < .001).

CONCLUSIONS: LNG-IUS and DMPA induce hemodynamic changes in the uterine arteries denoting positive correlation with menstrual irregularities. Larger multicentre studies are warranted to potentiate our findings.