[Potential of new self-crosslinked hyaluronic acid gel on the recovery of endometrium after artificial abortion: a multicenter, prospective randomized controlled trial].

Objective: To evaluate the impact of self-crosslinked hyaluronic acid (SCH) gel on endometrium recovery after artificial abortion. Methods: A multicenter, prospective randomized controlled trial was conducted across 18 hospitals from December 2021 to February 2023, involving 382 women who underwent artificial abortion. Participants were randomly allocated to receive either treatment with SCH gel (SCH group) or no treatment (control group) in a 1∶1 ratio. The primary outcome was endometrium thickness in 14 to 18 days after the first postoperative menstruation. Secondary outcomes included changes in menstrual volume during the first postoperative menstruation, menstruation resumption within 6 postoperative weeks, time to menstruation resumption, duration of the first postoperative menstruation, and incidence of dysmenorrhea. Results: Baseline characteristics of participants were comparable between the two groups (all P>0.05), with 95.3% (182/191) in SCH group and 92.7% (177/191) in the control group completed the study. The postoperative endometrial thickness in SCH group was significantly greater than that in the control group [(9.78±3.15) vs (8.95±2.32) mm; P=0.005]. SCH group also had significantly fewer participants with reduced menstrual volume [23 cases (12.6%, 23/182) vs 31 cases (17.5%, 31/177); P=0.038]. Although SCH group experienced less dysmenorrhea during the first postoperative menstrual period, this difference was not statistically significant [28.5% (51/179) vs 37.1% (65/175); P=0.083]. Outcomes were similar between SCH group and the control group regarding the proportion of participants who resumed menstruation within 6 weeks postoperatively, time to menstruation resumption, and duration of the first postoperative menstruation (P=0.792, 0.485, and 0.254, respectively). No serious adverse events were observed during the study period, and no adverse events were attributed to SCH gel treatment. Conclusion: The application of SCH gel after artificial abortion is safe and might aid in the recovery of the endometrium.