Prediction of Pregnancy Complications With Maternal Biochemical Markers Used in Down Syndrome Screening

Abstract

Objective: To determine whether first-and second-trimester maternal serum biomarkers are useful for the prediction of pregnancy complications like preterm birth, intrauterine growth restriction (IUGR), and macrosomia.Methods: We conducted a retrospective analysis of 353 women having first-or second-trimester combined test for Down syndrome screening who delivered at our institution between January 2018 and December 2020. Associations between first-and second-trimester serum markers and adverse pregnancy outcomes among those who underwent prenatal screening for Down syndrome in our clinic were studied. The adverse pregnancy outcomes, serum levels of pregnancy-associated plasma protein-A (PAPP-A), β-human chorionic gonadotropin (β-hCG), and maternal serum alpha-fetoprotein (ms-AFP) were recorded and analyzed. Correlation analyses of PAPP-A, free βhCG, and ms-AFP with pregnancy outcomes were studied. We sought to predict the risks of preterm delivery (PTD, <37 weeks gestational age), low birth weight (LBW, <2500 grams) and macrosomia (>4000 grams).Results: A total of 353 women who had first-and second-trimester screening test for Down syndrome were included. Two hundred fifty (70.08%) of them had first-trimester and 103 (41.2%) had second-trimester test. Mean age of the patients who underwent screening test for Down syndrome was 29.3±5.9, mean maternal weight was 67.3±13.6, mean gestational weeks at birth was 38.6±2.1 weeks and mean birth weight was 3260.9±511.1, preterm birth rate was 40/353 (11.3%), IUGR rate was 21/353 (5.9%), macrosomia rate was 17/353 (4.8%), stillbirth rate was 3/353 (0.8%). When laboratory and clinical parameters affecting birth weight and birth weeks were analysed in correlation analysis, both birth week and birth weight were found to be positively correlated with maternal weight. Of first-trimester markers Papp-A MoM (Multiples of Median) was found to be positively correlated with fetal birth weight (p = 0.044). Of second-trimester biochemical parameters ms-AFP was found to be negatively correlated with fetal birth weight (p = 0.039). Conclusion:The study concluded that there is a relationship between serum markers and adverse pregnancy outcomes. Significant associations were found between the levels of first-and second-trimester serum markers PAPP-A, AFP and IUGR, macromia and additionally significant association was found between maternal weight and both delivery week and fetal weight. These results can highlight the pregnancies at risk and follow-up intervals may be arranged according to risk scala which may help at antenatal follow-up of high-risk patients.

First-Trimester Screening Tests and Perinatal Outcomes

“…In these studies, no adjustments were made for smoking and maternal weight 9 . In another study 1622 pregnant women who were in IUGR and examined the levels of PAPP-A, free β-hCG, and fetal NT between the groups, and they found that only the PAPP-A level was 3.3 times significant in detecting IUGR below 0.50 MoM 10 . In the group with IUGR, PAPP-A was successful in predicting IUGR with an odds ratio (OR) value of 5.4, a sensitivity of 3.3%, specificity of 99.3%, and a positive predictive value (PPV) of 24.1%, below 0.29 MoM, which is the 1st MoM.…”

Pruebas de screening prenatal para la detección temprana de cromosomopatías

“…Estos marcadores serológicos se combinaron con la prueba de translucencia nucal fetal (NT) y dieron lugar a las pruebas triples y cuádruples. Varios estudios han demostrado que estas pruebas tienen una alta tasa de detección, alrededor del 80% al 90% para trisomía 21 en el primer trimestre del embarazo, con alrededor del 5 % de falsos positivos (9,13).…”

“…A partir de la semana 12, los niveles de beta β-hCG se equilibran y alcanzan concentraciones de 1 MoM en embarazos euploides (21,22). La PAAP-A es una proteasa que se secreta en la placenta específicamente en las células del sincitiotrofoblasto, luego se transporta a la circulación sanguínea materna y la concentración incrementa a medida que transcurre el tiempo de embarazo (13).…”

“…Por lo tanto, el autor afirma que las pruebas serológicas no deben realizarse de forma independiente de las pruebas de ultrasonografía en el primer trimestre de embarazo (9). Sin embargo Harfsheno et al (10) y Ozdemir et al (13), respaldan la asociación de valores bajos de PAPP-A y β-hCG libre con un bajo peso al nacer, muerte fetal, parto prematuro y el riesgo de trisomías, entre otros. Por su parte Harfsheno et al (10) afirmaron en su investigación que no existe una relación significativa entre los marcadores serológicos y las pruebas de translucencia nucal fetal (NT) durante el primer trimestre de embarazo.…”

Relationship between increased maternal serum free human chorionic gonadotropin levels in the second trimester and adverse pregnancy outcomes: a retrospective cohort study

“…There was no agreement on the relationship between serum free β-hCG levels and adverse pregnancy outcomes (APO). Ozdemir et al [ 7 ] reported correlations of the levels of the first- and second-trimester serum markers plasma protein-A (PAPP-A) and alpha-fetoprotein (AFP) with intrauterine growth restriction (IUGR) and macrosomia. In the absence of medically-indicated risk factors for premature delivery, the elevated serum free β-hCG levels of first- and second-trimester pregnant women are associated with a reduced likelihood of spontaneous preterm birth [ 8 ].…”