Adenomyomectomy, a therapeutic option for women with adenomyosis who wish to preserve their fertility, has been reported to pose a risk of developing placenta accreta spectrum (PAS) and uterine rupture in future pregnancies. However, the specific clinical factors contributing to these occurrences remain elusive. This study aimed to explore the association between hysteroscopic findings after adenomyomectomy and the incidence of PAS in subsequent pregnancies. We conducted a retrospective analysis of 10 patients (11 pregnancies) who had undergone hysteroscopy following adenomyomectomy and had later delivered at our hospital. In 6/10 patients, postoperative hysteroscopy revealed endometrial defects. However, subsequent evaluations confirmed endometrial restoration within 7-21 months, with five patients achieving pregnancy afterward. The only other patient conceived naturally without waiting for endometrial restoration, resulting in uterine rupture from the site of the placenta percreta. The incidence of clinically diagnosed PAS during cesarean section was 100% (1/1) in pregnancies with preconceptional endometrial defects, 20% (1/5) in those with endometrial restoration, and 0% (0/5) in pregnancies without endometrial defects. Similarly, the incidence of pathologically diagnosed PAS was 100% (1/1), 60% (3/5), and 20% (1/5) in these groups, respectively. Thus, endometrial defects were frequently detected after adenomyomectomy and recovered over time, whereas one patient without endometrial restoration developed uterine rupture complicated by PAS. This study demonstrates that while the presence of an endometrial defect identified by postoperative hysteroscopy may be a risk factor for the occurrence of PAS in subsequent pregnancies, allowing sufficient recovery time for the endometrium may help reduce the risk of uterine rupture.