Influence of adenomyosis on pregnancy and perinatal outcomes in women with endometriosis.

OBJECTIVES: Several studies have investigated the correlation between endometriosis and adverse pregnancy and perinatal outcomes. However, the role of adenomyosis as a risk factor for adverse perinatal outcome in women with endometriosis has yet to be established. The aim of this study was to explore if fetal and maternal outcomes, in particular the incidence of a small-for-gestational-age (SGA) infant, are different in pregnant women with endometriosis only from in those with the concomitant presence of diffuse or focal adenomyosis.

METHODS: This was a retrospective analysis of data collected prospectively during a 3-year period. We included 206 pregnant women with endometriosis: 148 (71.8%) with endometriosis only, 38 (18.4%) with focal adenomyosis and 20 (9.7%) with diffuse adenomyosis. Adenomyosis was diagnosed using ultrasonography and was classified as focal or diffuse. The study included patients who conceived spontaneously or by an assisted reproductive technique. Demographics, ultrasound variables and outcome were compared between women with endometriosis only and those with diffuse and those with focal adenomyosis. Logistic regression analysis was performed to assess the association of variables with SGA at birth in women with diffuse and those with focal adenomyosis.

RESULTS: The three groups were similar in demographic characteristics (age, body mass index, mode of conception). Patients with diffuse adenomyosis compared with those with endometriosis only had significantly lower pregnancy-associated plasma protein A (0.61 vs 0.88 multiple of the median, P < 0.001), higher mean uterine artery pulsatility index in the first (2.23 vs 1.67, P < 0.001) and second (1.30 vs 0.94, P < 0.001) trimesters of pregnancy, and higher incidence of SGA (40% vs 10.8%, P < 0.001). No statistically significant differences were found in patients with focal adenomyosis compared with those with endometriosis only. Logistic regression analysis demonstrated that diffuse adenomyosis (odds ratio = 3.744; 95% CI, 1.158-12.099; P = 0.027) was the only independent risk factor for SGA.

CONCLUSIONS: The presence of diffuse adenomyosis in pregnant women with endometriosis is strongly associated with delivery of a SGA infant. Women with diffuse adenomyosis should be treated as being at high risk of placental dysfunction, and these pregnancies might therefore need closer monitoring. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.