Hysteroscopy not better than vacuum aspiration for managing incomplete miscarriage

The use of hysteroscopy for surgical management of incomplete spontaneous abortion in individuals who intend to conceive again neither leads to more subsequent births nor shows a better safety profile compared with vacuum aspiration, according to the results of the HY-PER trial.

HY-PER included 574 adult participants who were scheduled to receive a surgical procedure for an incomplete miscarriage with plans to subsequently conceive. These participants were randomly assigned to undergo surgical treatment by hysteroscopy (n=288) or vacuum aspiration (n=286). The primary outcome was a pregnancy with a duration of at least 22 weeks over a 2-year follow-up.

Of the participants, 563 (mean age 32.6 years) were included in the intention-to-treat analyses. All vacuum aspiration procedures were completed. On the other hand, the hysteroscopic procedure could not be completed for 19 patients (7 percent), with 18 of them having to undergo vacuum aspiration instead. Reasons for incomplete hysteroscopic procedure for the 18 participants were as follows: inability to completely resect (n=8), insufficient visualization (n=7), anaesthetic complications that required a shortened procedure (n=2), equipment failure (n=1). For one participant, hysteroscopy failed due to a false passage during cervical dilatation.

The primary outcome occurred in 177 participants in the hysteroscopy group and 190 in the vacuum aspiration group (62.8 percent vs 67.6 percent; difference, −4.8 percent, 95 percent confidence interval [CI], −13 to 3.0; p=0.23). The time-to-event analyses showed that the primary outcome did not significantly differ between the two groups (hazard ratio, 0.87, 95 percent CI, 0.71–1.07).

Notably, the duration of surgery and hospitalization was much longer in the hysteroscopy than in the aspiration group. Otherwise, rates of new miscarriages, ectopic pregnancies, Clavien-Dindo surgical complications of grade 3 or above (requiring surgical, endoscopic, or radiological intervention or life-threatening event or death), and reinterventions to remove remaining products of conception were similar.