EP04.20: Increased rates of pregnancy complications after positive screening results

Abstract

A number of retrospective studies have described the high rate of adverse outcomes after false-positive results (FP) for fetal aneuploidy (FA) especially in cases of screen-positives for multiple pathologies, but no prospective study has been commissioned in the Russian population. The aim of this study was to determine whether a euploid fetus at high risk for multiple conditions – specifically, FA and pre-term SGA (pSGA) – has a more unfavorable forecast than a fetus with negative screening results. This was a prospective study on screening for FA and pSGA in 3504 singleton pregnancies by the Fetal Medicine Foundation algorithm that combines maternal factors, mean arterial pressure, maternal serum biochemistry (free b-hCG and PAPP-A), ultrasound markers (nuchal translucency thickness, tricuspid valve and ductus venosus flow, nasal bone), and uterine artery pulsatility index at 11-13 weeks' gestation at Fetal Medicine Center (Russian Federation). We excluded 1428 cases because of loss to follow-up (n = 1269) and fetal abnormalities (n = 159). With the proposed cut-offs of ≤ 1:100 for trisomies, and ≤ 1:150 for pSGA the study population of 2076 was divided into: Group 1: FP for FA (n = 55), including high (n = 32) and low (n = 23) risk for pSGA; Group 2: low-risk for FA and pSGA (n = 1563). The remaining 458 cases with low-risk for FA and high risk for pSGA were also excluded from further analysis. Data on pregnancy outcomes were collected by telephone interviews. The rates of miscarriage were 9.1% vs. 0.7%; preterm birth 23.6% vs 3.97%; perinatal death 3.6% vs. 0.06%; NICU admissions in 12.73% vs. 2.4%, SGA 16.36% vs 3.67%, pSGA 10.9% vs 0.45% in 1st and 2nd group, respectively (p < 0.001). Additionally, in the 1st group the rates of preterm birth were 37.2% vs 4.3% and SGA 36% vs 0% in cases with high and low risk for pSGA, respectively (p < 0.05). The majority of perinatal complications are common in pregnancies false-positive results for fetal aneuploidy, especially accompanied with high risk for pSGA. These pregnancies should be closely followed up until delivery. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.