Confined placental mosaicism and the association with pregna
Mosaicism at all different stages can be associated with adverse pregnancy outcomes.

The objective of this review is to evaluate the association between confined placental mosaicism (CPM) and prenatal growth and adverse pregnancy outcomes. All relevant literature has been reviewed in order to achieve an overview of merged results exploring the relation between CPM and fetal growth restriction (FGR) and other adverse pregnancy outcomes.

There were 823 articles found and screened. From these, 213 articles were selected and full-text versions were obtained for a second selection, after which 70 publications were included and 328 cases (fetuses) were analyzed.

- For CPM in eight different chromosomes (of the total 14 analyzed), there was sufficient evidence that birth weight was often below the 5th percentile of fetal growth standards.

- FGR was reported in 71.7% of CPM cases and preterm birth was reported in 31.0% of cases.

- A high rate of structural fetal anomalies, 24.2%, in cases with CPM was also identified. High levels of mosaicism in CVS and the presence of uniparental disomy (UPD) were significantly associated with adverse pregnancy outcomes.

Based on the literature, the advice to clinicians is to monitor fetal growth intensively from the first trimester onwards in case of CPM, especially when chromosomes 2, 3, 7, 13, 15, 16, and 22 are involved. In addition to this, it is advised to examine the fetuses thoroughly for structural fetal anomalies and raise awareness of a higher chance of (possibly extreme) premature birth.

Human Reproduction Update