OC26.04: Influence of adenomyosis on pregnancy outcome and first and second trimester markers of impaired implantation in women with endometriosis

Several studies investigated the correlation between endometriosis and adverse pregnancy and perinatal outcomes. However, the role of adenomyosis as a risk factor for adverse perinatal outcomes in women with endometriosis has yet to be established. This study aimed to explore the fetal and maternal outcomes of patients with endometriosis with or without adenomyosis. This prospective study included 206 patients with endometriosis: 148 did not have adenomyosis, 38 had focal adenomyosis and 20 had diffuse adenomyosis. Patients had histological or ultrasonographic diagnosis of endometriosis. Adenomyosis was diagnosed by ultrasonography. Pregnancies with major fetal structural abnormalities, aneuploidy or multiple gestations were excluded. The three groups were similar in demographic characteristics (age, body mass index, mode of conception). Patients with diffuse adenomyosis compared with those with only endometriosis had significantly lower PAPP-A MoM (0.61 vs 0.88 MoM, p < 0.001) during the first trimester, higher mean uterine artery pulsatility index (UtA PI) in the 1st (2.23 vs 1.67, p < 0.001) and 2nd (1.30 vs 0.94, p < 0.001) trimester of pregnancy, and higher incidence of small for gestational age (SGA) infants (40% vs 14.3%, p < 0.001; respectively). No statistically significant difference was found in fetal and maternal outcomes of patients with focal adenomyosis compared to those with only endometriosis. Logistic regression analysis demonstrated that 2nd trimester UtA PI (OR = 4.887 CI 95% 1.287-18.566; p = 0.020) and diffuse adenomyosis (OR = 3.902 CI 95%1.161-13.110; p = 0.028) were the two only independent risk factors for SGA. The presence of diffuse adenomyosis in pregnant women with endometriosis is strongly associated with SGA infants. Women with endometriosis and diffuse adenomyosis should be treated as being at high risk of placental dysfunction, therefore, these pregnancies might need a closer monitoring.