Amnion rupture sequence in a first trimester missed abortion

Further insights into unusual acrania-exencephaly-anencephaly sequence caused by amniotic band – first trimester fetoscopic correlation with two- and three-dimensional ultrasound

Objectives

Antenatal detection of acrania-exencephaly-anencephaly (AEA) sequence beyond 10 completed weeks of gestation is usually straight-forward. An earlier detection and classification of the causative conditions prior to disaggregation of exposed dysplastic brain tissue remains challenging.

Case presentation

We present two- and three-dimensional ultrasound correlated with fetoscopic findings of an unusual type of neural tube defect at 11 gestational weeks caused by an amniotic constriction ring resulting in cystic degeneration of the developing skull.

Conclusions

By giving further illustrative insights into early defective brain development, this report confirms recent findings of an unusual subtype of acrania-exencephaly-anencephaly sequence suggesting early disruption of the developing brain, following an amniotic entrapment of the skull.

Transcervical fetoscopic diagnosis of structural defects in four first-trimester monochorionic twin intrauterine deaths

OBJECTIVE

While chromosomal abnormalities are often the cause of early failed pregnancies, other mechanisms could be involved in monochorionic twin intrauterine deaths, that might be screened for careful morphological analysis.

METHODS

Transcervical fetoscopy prior to instrumental evacuation of the uterus was performed in four first-trimester monochorionic twin intrauterine deaths.

RESULTS

We present fetoscopic and cytogenetic findings in four cases of monochorionic twin intrauterine deaths. In the first, generalized abnormal embryonic development observed in both twins was a manifestation of trisomy 20. The second (thoracophagus) and third (acardius) pair of twins had anomalies peculiar to multiple gestations. The fourth pair of twins was remarkable because of the concordance for the observed limb-reduction defects.

CONCLUSION

Malformations of first-trimester monochorionic twin intrauterine deaths might cover a wide spectrum of etiologies from abnormal chromosomes and single gene defects to rare duplication anomalies. Their detection by careful morphological analysis and the identification of a specific mechanism provides valuable information for genetic counseling and prenatal investigation in a future pregnancy.