Worldwide rates of Cesarean delivery have increased from about 6% in 1990 to 21% in 2015 [1], [2], [3]. National rates in the northern part of Europe are still below 20%, whereas those in the southeastern part of Europe, China, and South America have increased to or above 50% of deliveries [2]. In recent years, attention has inevitably turned to unintended consequences of liberalized caesarean section and to serious complications in subsequent pregnancies (i.e., uterine rupture, placenta accreta/percreta, postpartum hysterectomy and cesarean scar pregnancy (CSP)) [4], [5], [6], [7].

CSP is defined as a pregnancy that is implanted within the myometrium and the fibrous tissue of the scar of a previous caesarean section and is characterized by an empty uterus and cervical canal, a gestational sac located in the anterior uterine wall with diminished myometrium between the sac and the bladder, an area of increased peritrophoblastic or periplacental vascularity on color Doppler examination and a discontinuity in the anterior wall of the uterus adjacent to the gestational sac [8,9]. CSP occur in about 1 in 500 pregnancies among women who previously underwent cesarean delivery, account for 4% of ectopic pregnancies and can cause severe maternal morbidity and mortality [10,11]. If left untreated, CSP may lead to severe haemorrhage, uterine rupture and can evolve into an abnormally adherent placenta in the second and third trimester [12,13]. Moreover, given the deep implantation of CSP into the fibrous scar tissue of the lower uterine segment, treatment is challenging and may fail or cause haemorrhage and require hysterectomy [9,14].

Today, more than thirty CSP treatment regimens have been published, and the majority of recommendations are based on case series rather than on randomized controlled trials (RCTs) [4]. Medical management of CSPs include systemic injection of methotrexate (MTX); injection of MTX and/or potassium chloride (KCl) into the gestational sac; and, less commonly, oral mifepristone. Surgical management, eventually combined with medical therapy, include dilation and curettage (D&C); hysteroscopic, laparoscopic, vaginal, and open excision of CSP; and hysterectomy. Uterine artery chemoembolization (UAE), a combination of embolization and local delivery of chemotherapy, is a more recently conservative method for CSP and is usually undertaken before D&C and other surgical therapies or combined with medical treatment [9]. In general, UAE appears to be an effective treatment, with a success rate of 93%, a risk of haemorrhage of 5%, and a risk of hysterectomy of 3% and produces less morbidity when compared to other options [9,15]. On the other hand, the impact of this procedure on menstruation recovery and reproductive outcomes is still under debate. In particular, permanent damage to the uterine vasculature can not be excluded and, as chemoembolization blocked temporary uterine arterial blood flow, there is a concern about whether ovarian perfusion is affected [15]. On this basis, some authors, worried about long-term effects, proposed to use UAE only when the risk of heavy bleeding is very high such as in women with late gestational age or with a high blood flow on ultrasound or in women who initially present with heavy vaginal bleeding [9,16].

Clarifying the reproductive prognosis after UAE is of utmost relevance, especially considering that women diagnosed with CSP are mostly young and of previously proven fertility. In our hospital (Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, University of Milan, Milan, Italy), a third level referral center, bilateral UAE with gelatine sponge particles and intra-arterial MTX infusion entered in CSP clinical protocols in 2014. In order to disentangle this issue, we reviewed patients diagnosed with CSP between 2014 and 2018 to investigate their menstrual cycle recovery and reproductive potential after different treatment strategies.