(1) Background: The number of adnexal masses detected during pregnancy has increased due to the use of first-trimester screening and increasingly advanced maternal age. Despite their low risk of malignancy, other risks associated with these masses include torsion, rupture and labor obstruction. Correct diagnosis and management are needed to guarantee both maternal and fetal safety. Adnexal masses may be troublesome to classify during pregnancy due to the increased volume of the uterus and pregnancy-related hormonal changes. Management should be based on ultrasound examination to provide the best treatment. The aim of this study was to describe the ultrasound features of ovarian masses detected during pregnancy and to optimize and personalize their management with the expertise of gynecologists, oncologists and sonographers. (2) Methods: Clinical, ultrasound, histological parameters and type of management (surveillance vs. surgery) were retrospectively retrieved. Patient management, perinatal outcomes and follow-up were also evaluated. (3) Results: according to the literature, these masses are most frequently benign, ultrasound follow-up is the best management, and obstetric outcomes are not considerably influenced by the presence of adnexal masses. (4) Conclusions: the management of patients with ovarian masses detected during pregnancy should be based on ultrasound examination, and a centralization in referral centers for ovarian masses should be considered.

(1) Background: adnexal masses during pregnancy detection are increased due to the use of first trimester screening and to advanced maternal age. Although the low risk of malignancy, other risks are associated: torsion, rupture or labour obstruction. Correct diagnosis and management are fundamental to guarantee both maternal and fetal safety. Adnexal masses may be troublesome to classify during pregnancy due to the increase in the uterus volume and to pregnancy-related hormonal changes. Management should be based on ultrasound examination to provide the best treatment. (2) Methods: the aim was to describe the ultrasound features of ovarian masses detected during pregnancy. We evaluated patient’s management, perinatal outcomes and follow-up. (3) Results: our study demonstrated that the management should be guided by an accurate ultrasound examination performed by an expert operator according to standardized techniques. Secondly, our results confirm the data present in the literature: the masses are most frequently benign, ultrasound follow-up is the best management strategy and obstetric outcome is not considerably affected. (4) Conclusions: the management of patients with ovarian masses detected during pregnancy should be based on ultrasound examination and a centralization in referral centers for ovarian masses should be considered.