IntroductionThis study aimed to compare the outcomes of preterm infants given 12 vs. 24mg of betamethasone prophylaxis to understand whether a partial course of antenatal corticosteroids (CCS) could prevent or mitigate the major preterm birth complications.MethodsThis is a retrospective single-center cohort study including neonates born between 24 and 34 weeks of gestation from 2001 to 2019 at the University Hospital of Udine. The study population was divided into two groups: one group received 12mg, and another received a 24mg dose of betamethasone before the delivery. A separate analysis was performed for single and multiple pregnancies. The two groups were evaluated for various neonatal outcomes.ResultsThe study population included a total of 1,258 pregnancies and 1,543 neonates delivered between 24 and 34 weeks of gestation, of which 1,022 (803 single and 219 multiple pregnancies) were exposed to the complete CCS prophylaxis, whereas 236 (192 single and 44 multiple pregnancies) received the incomplete CCS prophylaxis. In single pregnancies, as for maternal characteristics, the most significant differences observed between the two groups are the following: a higher prevalence of spontaneous vaginal deliveries in the incomplete CCS prophylaxis (36.46 vs. 23.91%) and, by contrast, a higher prevalence of cesarean deliveries in the complete CCS prophylaxis group (75.72 vs. 63.02%). As for neonatal outcomes, the low Apgar score in the first and fifth min was significantly more prevalent in the incomplete CCS prophylaxis group compared with the complete CCS prophylaxis group. The group of incomplete CCS prophylaxis reported a higher occurrence of the following outcomes: IVH grade 3-4 (7.81 vs. 3.74%, p < 0.05), PVL (7.29 vs. 1.99% p < 0.05), ROP (23.96 vs. 18.06% p = 0.062), and RDS (84.38 vs. 78.83% p = 0.085). After adjusting for covariates, the complete CCS prophylaxis group in single pregnancies was significantly protective for IVH grade 3-4, PVL, and low Apgar's scores. Similar results were found in multiple pregnancies except for RDS.DiscussionThis retrospective single-center cohort study found that, compared with preterm infants treated with 24mg betamethasone in utero, those given half course of betamethasone had a significantly higher prevalence of IVH grade 3-4, PVL, RDS, and lower Apgar scores at 1 and 5 min. In conclusion, the evidence from this single-center retrospective study supports the preference for the complete CCS prophylaxis in women at risk of preterm birth because of its beneficial effect on the main adverse outcomes.

Background Monochorionic dizygotic twins are a rare condition, mostly related to assisted reproductive technology. This type of twinning is burdened by the same risk of pregnancy complications found in monochorionic monozygotic pregnancies. Case presentation We report a case of spontaneous monochorionic dizygotic twins sharing situs inversus abdominalis and isolated levocardia, with only one twin affected by biliary atresia with splenic malformation syndrome. We also conducted a literature review of the 14 available documented monochorionic dizygotic twin gestations spontaneously conceived. Conclusions It is still unclear how this unusual type of twinning can occur in spontaneous conception. The evidence so far suggest the importance to timely diagnose the chorionicity, in order to adequately manage the typical complications associated with monochorionicity.