What is the role of intrauterine transfusion after single intrauterine death in monochorionic twin pregnancies? Evidence from a systematic review and meta-analysis

To investigate the role of intrauterine transfusion (IUT) in affecting the outcome of the surviving twin showing sign of fetal anemia after a single intrauterine fetal death (IUFD) in monochorionic (MC) twin pregnancies. PubMed, Medline and Embase databases were searched (2010–2024). The inclusion criteria were studies reporting the outcome of fetuses showing signs of fetal anemia, defined as the presence of the peak systolic velocity (PSV) of the middle cerebral artery (MCA) >1.5 MoM, after single IUFD receiving compared to those not receiving IUT. The outcomes observed were preterm birth (PTB) Six studies (78 twin pregnancies complicated by single IUFD showing signs of fetal anemia) were included in the systematic review. Assessment of risk of bias of observational studies according to the ROBINS-I tool is presented. Only one study reported a non-matched comparison between anemic fetuses undergoing compared to those not undergoing IUT, so we could not calculate the summary odd ratios, and we reported the results as pooled proportions. PTB occurred in 51.25% (95% CI 35.76–66.62) of cases There is a very low grade of evidence that IUT can affect the outcome of anemic fetuses after single IUFD in MC pregnancies. The findings how this systematic review, in view of the limitations of the included studies, highlighted the need for large multicenter studies sharing objective protocols of prenatal management and post-natal assessment of pregnancies complicated by single IUFD are needed to report whether IUT in the anemic fetus after single IUFD can prevent mortality and neuromorbidity.