[Ongoing pregnancy rate with intervention and expectant therapy in patients with unexplained recurrent spontaneous abortion: a prospective multicenter cohort study].

<b>Objective:</b> To observe the pregnancy outcomes of patients with unexplained recurrent spontaneous abortion (URSA) after interventional treatment or expectant treatment. <b>Methods:</b> This prospective study followed up 398 patients with recurrent spontaneous abortion from March 2017 to September 2022 in seven hospitals. Among them, 267 patients were diagnosed with URSA, including 124 patients who were initially diagnosed in the interventional treatment hospital and 143 patients who were initially diagnosed in the expectant treatment hospital. All URSA patients were followed up for 33 months. Ongoing pregnancy rates were observed as main outcome indicators. <b>Results:</b> A total of 127 patients became pregnant, and 107 of them had sustained pregnancies, the ongoing pregnancy rate was 84.25% (107/127). The ongoing pregnancy rate was 86.11% (31/36) in the interventional treatment group and 83.52% (76/91) in the expectant treatment group, with no significant difference (<i>P</i>>0.05). During the follow-up, the ongoing pregnancy rates in the interventional treatment hospital and the expectant treatment hospital were 75.71% (53/70) and 94.74% (54/57), respectively, with a significant difference (<i>P</i><0.05). The ongoing pregnancy rate after interventional treatment in the interventional treatment hospital was 82.76% (24/29), which was similar to the 94.00% (47/50) after expectant treatment in the expectant treatment hospital (<i>P</i>>0.05). <b>Conclusion:</b> The ongoing pregnancy rate of interventional treatment for URSA patients has not been significantly improved, suggesting that it may not be necessary to carry out this treatment.