Background
The risk of uterine rupture is a major concern for women who become pregnant after undergoing an adenomyomectomy.

Aims
The aim of this study was to investigate the association of uterine wall thickness with pregnancy outcome.

Materials and Methods
Uterine wall thickness was measured using sonography and/or magnetic resonance imaging in 23 pregnant women who underwent uterine‐sparing surgery for diffuse uterine adenomyosis prior to conception.

Results
Of the 23 women, 10 (43.5%) had an early miscarriage and 13 (56.5%) proceeded to delivery. Of the ten early miscarriage cases, two had a uterine rupture caused by excision of the uterine wall to within 7 mm.

Conclusions
Wall thickness of the excised uterus was highly associated with uterine rupture. We concluded that optimum wall thickness for conception and preventing uterine rupture during pregnancy may range from 9 to 15 mm.