The Role of Adenomyosis in the Pathogenesis of Preeclampsia

Adenomyosis can cause defective deep placentation. Preeclampsia is known to be associated with abnormal placentation. The aim of this study was to compare the presence of adenomyosis on magnetic resonance imaging in patients with and without history of preeclampsia in order to investigate the possible role of adenomyosis in the pathogenesis of preeclampsia.

This prospective, randomized study consisted of patients with (n = 35) and without (n = 34) history of preeclampsia. Direct (submucosal microcysts, adenomyoma and cystic adenomyoma) and indirect (maximal thickness of junctional zone, ratio of maximal thickness of junctional zone to myometrial thickness, junctional zone differential, focal thickening of junctional zone, globally enlarged uterus and non-uniform junctional zone contours) signs of adenomyosis were assessed by pelvic magnetic resonance imaging.

The prevalence of adenomyosis was found to be more common in patients with preeclampsia und fetal growth restriction compared to patients without fetal growth restriction (94.4 vs. 64.7 %; p = 0.041), respectively. There was a strong association between maximal thickness of junctional zone (9 vs. 13 mm, p = 0.005), ratio of maximal thickness of junctional zone to myometrial thickness (0.42 vs. 0.66, p = 0.001) and junctional zone differential (3 vs. 5 mm, p = 0.02) and late-onset preeclampsia.

Presence of adenomyoma is more common in patients with preeclampsia complicated with fetal growth restriction. Indirect signs of adenomyosis detected on pelvic magnetic resonance imaging might have a role in the pathogenesis of late-onset preeclampsia.