Bleeding and spotting with the levonorgestrel 13.5 mg intrauterine system: the impact of insertion timing

Abstract

Objective: To assess the impact of early versus late menstrual cycle insertion on bleeding/spotting in the 90 days following levonorgestrel (LNG) 13.5 mg intrauterine system (IUS) insertion.

Study design: In this observational study, participants received a LNG 13.5 mg IUS and provided 90 days of bleeding/spotting data by answering the following daily text: "Have you had no flow (0), spotting (1), or bleeding (2) today?" We dichotomized insertion timing as early (days 1-7 from last menstrual period) and late (remainder of menstrual cycle) and compared bleeding/spotting between the two groups in the 90- and 30-day reference periods. We used multivariate regression methods to study associations between cycle day at insertion, parity, historical bleeding, recent hormonal contraceptive use and bleeding/spotting.

Results: In the 90-day dichotomous analysis (n=125), we found no differences in the number of days of bleeding/spotting, bleeding or spotting between the early and late insertion groups. In the 30-day dichotomous analysis (n=131), early insertion was associated with fewer days of bleeding than late insertion (5±3 vs. 7±4 days, p<.01). Recent hormonal contraceptive users experienced fewer days of bleeding than new users (5±4 vs. 7±3 days, p<.01). In the 90- and 30-day regression models, earlier insertion was associated with fewer days of bleeding (p=.02, p=.02). Recent contraceptive use was associated with fewer days of bleeding/spotting (90-day, p=.03) and fewer days of bleeding (30-day, p<.01). Nulliparity was associated with spotting (30-day, p=.04).

Conclusions: Early cycle insertion does not impact 90-day bleeding/spotting. Early cycle insertion and recent hormonal contraceptive use decrease 30-day bleeding.

Implications: The LNG 13.5 mg IUS may be inserted throughout the menstrual cycle with small differences in bleeding patterns in the 30 but not the 90 days following insertion. Shared decision making should determine timing of insertion.

Trial registration: ClinicalTrials.gov NCT03074903.

Keywords: Bleeding; Bleeding pattern; Insertion timing; Intrauterine system; Levonorgestrel intrauterine system; Spotting.