Triplet pregnancies are rare events that affect approximately 93 in 100,000 deliveries in the world, especially due to the increased use of assisted reproductive techniques and older maternal age. Triplet pregnancies are associated with a higher risk of fetal and maternal morbidity and mortality compared to twins and singletons. Chorionicity has been proposed as a major determinant of perinatal and maternal outcomes in triplet pregnancies, although further evidence is needed to clarify the extent and real influence of this factor. Thus, the aim of this study was to conduct a systematic review of the literature and a meta-analysis of the maternal and perinatal outcomes of triplet pregnancies, evaluating how chorionicity may influence these results. A total of 46 studies with 43,653 triplet pregnancies and 128,145 live births were included. Among the main results of our study, we found a broad spectrum of fetal and maternal complications, especially in the group of monochorionic and dichorionic pregnancies. Risk of admission to NICU, respiratory distress, sepsis, necrotizing enterocolitis, perinatal and intrauterine mortality were all found to be higher in non-TCTA pregnancies than in TCTA pregnancies. To date, our meta-analysis includes the largest population sample and number of studies conducted in this field, evaluating a wide variety of outcome measures. The heterogeneity and retrospective design of the studies included in our research represent the main limitations of this review. More evidence is needed to fully assess outcome measures that could not be studied in this review due to scarcity of publications or insufficient sample size.

Preeclampsia is one of the most worrisome complications during pregnancy, affecting approximately 1 out of 20 women worldwide. Preeclampsia is mainly characterized by a sustained hypertension, proteinuria, also involving a significant organ dysfunction. Moreover, 25% of the cases could be classified as severe preeclampsia (SP), a serious condition that could be life-threatening for both the mother and fetus. Although there are many studies focusing on preeclampsia, less efforts have been made in SP, frequently limited to some specific situations. Thus, the present study aims to conduct a comparative analysis of risk factors, maternal characteristics, obstetric and neonatal outcomes and maternal complications in patients with severe preeclampsia versus patients without severe preeclampsia. Hence, 235 cases and 470 controls were evaluated and followed in our study. We described a set of variables related to the development of severe preeclampsia, including maternal age > 35 years (69.8%), gestational (26.8%) or chronic arterial hypertension (18.3%), obesity (22.6%), use of assisted reproduction techniques (12.3%), prior history of preeclampsia (10.2%) and chronic kidney disease (7.7%) All patients had severe hypertension (>160 mmHg) and some of them presented with additional complications, such as acute renal failure (51 cases), HELLP syndrome (22 cases), eclampsia (9 cases) and acute cerebrovascular accidents (3 cases). No case of maternal death was recorded, although the SP group had a higher cesarean section rate than the control group (60% vs. 20.9%) (p < 0.001), and there was a notably higher perinatal morbidity and mortality in these patients, who had a prematurity rate of 58.3% (p < 0.001) and 14 perinatal deaths, compared to 1 in the control group. Overall, our study recognized a series of factors related to the development of SP and related complications, which may be of great aid for improving the clinical management of this condition.