Obstetrical Outcomes of Amniocentesis or Chorionic Villus Sampling in Dichorionic Twin Pregnancies

BACKGROUND: Under certain situations, women with twin pregnancies may be counseled to undergo invasive prenatal diagnostic testing. Chorionic villus sampling and amniocentesis are the two generally performed invasive prenatal diagnostic tests. Studies comparing procedure-related fetal loss between first-trimester chorionic villus sampling and second-trimester amniocentesis in twin pregnancies are limited. This study aimed to evaluate the procedure-related fetal loss and the obstetrical outcomes of these two procedures, chorionic villus sampling and amniocentesis in twin pregnancies. METHODS: The data from dichorionic-diamniotic twin pregnancies on which first-trimester chorionic villus sampling (n = 54) or second-trimester amniocentesis (n = 170) was performed between December 2006 and January 2017 in a single center were retrospectively analyzed. The procedure-related fetal loss was classified as loss of one or all fetuses within 4 weeks of procedure, and overall fetal loss was classified as loss of one or all fetuses during the gestation. The groups were compared with respect to the procedure-related and obstetrical outcomes. RESULTS: The difference in proportion of procedure-related fetal loss rate (1.9% for chorionic villus sampling vs. 1.8% for amniocentesis; P = 1.000) and the overall fetal loss rate (7.4% for chorionic villus sampling vs. 4.7% for amniocentesis; P = 0.489) between the two groups was not significant. The mean gestational ages at delivery were not statistically significant. CONCLUSION: Both the overall fetal loss rate and the procedure-related fetal loss rate of chorionic villus sampling and amniocentesis in dichorionic twin pregnancies had no statistical significance. Both procedures can be safely used individually.

Clinical significance of sonographic soft markers: A review

Sonographic findings with little or no pathological significance, known as soft markers, are often found in aneuploidy fetuses. After normal screening for the aneuploidy in first trimester, there are no uniform recommendations regarding when to disregard or put on clinical significance in isolated soft markers. Associations between some soft markers and adverse pregnancy outcomes including intrauterine fetal death, preterm birth, fetal growth restriction, and congenital infection have been reported in euploidy fetuses. The present article aims to review recent literatures about the clinical significance of soft markers after normal first trimester combined screening or noninvasive prenatal testing, and propose a simple clinical summary for management of specific soft markers in pregnancies.