Although the main cause of megacystis is LUTO, an enlarged fetal bladder can also be present as corollary finding of miscellaneous genetic syndromes, developmental disturbances and chromosomal abnormalities. This study provides an overview of the structural anomalies and congenital disorders associated with megacystis and proposes a flowchart for the differential diagnosis of genetic syndromes, chromosomal and developmental abnormalities, focusing on the morphological examination of the fetus. This article is protected by copyright. All rights reserved.

Human Leukocyte Antigen (HLA)-G is involved in reprogramming immune responses at fetal-maternal interface during pregnancy. We evaluated the genetic diversity of the 3′ Un-Translated Region (UTR) of HLA-G, previously associated with HLA-G mRNA post-transcriptional regulation, in women with unexplained Recurrent Pregnancy Loss (RPL), with 2 pregnancy losses (RPL-2, n = 28), or 3 or more pregnancy losses (RPL-3, n = 24), and in 30 women with a history of successful pregnancy. Results showed in RPL-2, but not in RPL-3, women compared to controls: i) higher frequency of the 14 bp Ins allele, in single and in double copy; ii) significantly lower frequency of DelG/X genotype, iii) reduced frequency of the UTR-2, and UTR-3 haplotypes; iv) higher frequencies of the UTR-5, UTR-7, and UTR-8 haplotypes. This pilot study supports the relevance of performing 3′UTR HLA-G genetic screening, not limited to a specific polymorphism, but considering the extended haplotypes, as a possible predictor of pregnancy outcome.

In conclusion, women affected by type I OI represent a subset of patients whose pregnancies should be considered high risk and warrant a multidisciplinary approach in a referral center.