Background and Objective: The aim of this retrospective cohort study is to evaluate the impact of assisted reproductive treatment (ART) on adverse maternal outcomes and the rate of hospitalization in maternal intensive care (MIC) in a tertiary university center in Liege, Belgium. Materials and Methods: This is a retrospective cohort study comparing two groups, 6557 patients who achieved pregnancy spontaneously and 330 patients who achieved pregnancy after ART, between January 2020 and December 2022. These patients were followed in the academic obstetrics department of Citadelle Hospital, Liège. The database of the ART center was compared with the database of the delivery unit to determine the cohort of patients who conceived after ART. Adverse maternal outcomes and MIC hospitalization rates were compared with between spontaneous pregnancies and ART groups. ART groups were also compared with each other. Results: The rate of hospitalization in maternal intensive care for patients who achieved pregnancy spontaneously was 12.1%, compared to 17.3% after ART. Comparing the rate of pre-eclampsia, 3.5% of spontaneous pregnancies were complicated by pre-eclampsia, while after ART, 10.9% of patients developed this complication during pregnancy. This rate was higher after IVF (12%) compared to intrauterine insemination and particularly after frozen embryo transfer (FET) in artificial cycle (17.9%). The birthweight of newborns after ART was also analyzed. A significant difference was obtained when comparing fresh embryo transfer with FET. Conclusions: Our study confirmed that FET in artificial cycle is a risk factor for pre-eclampsia and that fresh embryo transfer is associated with a higher rate of newborns with a lower percentile of birthweight. Our data showed that the rate of MIC hospitalization was significantly higher after ART but did not differ between groups.

Introduction Pregnancies resulting from in vitro fertilisation are associated with an increased risk of developing hypertensive disorders of pregnancy, such as preeclampsia, when compared with naturally conceived pregnancies. Objective The efficacy of aspirin prophylaxis to reduce the incidence of preeclampsia is well established in naturally conceived pregnancies identified as high risk for developing preeclampsia. However, the efficacy of aspirin to reduce the rate of preeclampsia for all pregnancies resulting from in vitro fertilisation remains uncertain, although in vitro fertilisation conception is a well-known risk factor for preeclampsia. Therefore, the purpose of this scoping review is to provide a comprehensive overview of the current literature regarding the use of low-dose aspirin to prevent hypertensive disorders of pregnancy after in vitro fertilisation. Inclusion criteria This review will identify all peer-reviewed published articles including pregnant women who underwent embryo transfer after in vitro fertilisation and were prescribed low-dose aspirin to reduce the risk of hypertensive disorders of pregnancy. Methods We have devised a comprehensive search strategy to systematically identify pertinent studies published from January 2000 until May 2024, within the Medline (PubMed interface), Embase and Scopus databases. The search strategy is based on the keywords ‘aspirin,’ ‘pregnancy-induced hypertension,’ and (‘in vitro fertilization’ OR ‘oocyte donation’ OR ‘embryo transfer’ OR ‘donor conception’). Two reviewers will independently screen the titles, abstracts and full-text articles to select the relevant articles, using the Covidence software. Ethics and dissemination No patients are involved in this study. This study aims to be published in a peer-reviewed journal and could be presented at a conference.