The relationship between first-trimester pregnancy-associated plasma protein-A levels and intrapartum fetal distress development

First-trimester maternal serum biomarkers and the risk of cerebral palsy

AIM

To investigate whether combined first-trimester screening (cFTS) biomarkers are associated with cerebral palsy (CP) and to identify CP characteristics associated with abnormal biomarker levels.

METHOD

In this retrospective case-control data linkage study, we matched mothers of 435 singletons with CP from a population register to their cFTS records and selected 10 singleton pregnancy controls per case. We compared mean and abnormal levels (expressed as multiples of the median [MoMs]) of pregnancy-associated plasma protein-A (PAPP-A), beta subunit of human chorionic gonadotrophin (β-hCG), and nuchal translucency between cases and controls and between CP subgroups.

RESULTS

Compared with control pregnancies, CP pregnancies had lower mean levels of PAPP-A (0.95 vs 1.01 MoM, p=0.02) and β-hCG (0.93 vs 0.99 MoM, p=0.02). Biomarker levels in CP pregnancies were 1.8 times more likely to be associated with abnormally low levels of PAPP-A (p<0.01), 1.4 times for β-hCG (p=0.12), and 2.6 times for low PAPP-A and β-hCG together (p=0.04). In cases with CP, an abnormally low PAPP-A level was associated with moderate preterm birth, low Apgar scores, and Gross Motor Function Classification System level V. Low β-hCG was associated with very low birthweight.

INTERPRETATION

Low first-trimester biomarker levels suggest a role for early pregnancy factors in some causal pathways to CP.

WHAT THIS PAPER ADDS

Low first-trimester levels of biomarkers in maternal serum are associated with later cerebral palsy (CP). Early pregnancy factors have potential importance in causal pathways to CP. Causal pathways involving preterm birth, term neonatal encephalopathy, and genetic syndromes may be implicated.

Low First Trimester Pregnancy-Associated Plasma Protein-A Levels Are Not Associated with an Increased Risk of Intrapartum Fetal Compromise or Adverse Neonatal Outcomes: A Retrospective Cohort Study

The aim of this study was to assess if women with a low first trimester maternal pregnancy-associated plasma protein-A (PAPP-A) level are at increased risk of emergency cesarean (EmCS) for intrapartum fetal compromise (IFC) and/or adverse neonatal outcomes. This was a retrospective cohort study performed at Mater Mother’s Hospital, Brisbane, Australia, between 2016 and 2018. All women with a singleton, euploid, non-anomalous fetus with a documented PAPP-A level measured between 10 ⁺⁰ and 13 ⁺⁶ weeks gestation during the study period were included. Data were extracted from the institution’s perinatal database and dichotomized according to PAPP-A level (≤0.4 Multiples of Medium (MoM) vs. >0.4 MoM). The primary outcomes were EmCS-IFC and a composite of severe adverse neonatal outcomes (SCNO). Nine thousand sixty-one pregnancies were included, 3.3% with a PAPP-A ≤ 0.4 MoM. Low maternal PAPP-A was not associated with an increased risk of EmCS-IFC (adjusted odds ratio (aOR) 0.77, 95% confidence interval (CI) 0.24–2.46, p = 0.66) or SCNO (aOR 0.65, 95% CI 0.39–1.07, p = 0.09). Low PAPP-A was associated with increased odds of pre-eclampsia, preterm birth and birthweight < 10th centile. In conclusion, low maternal PAPP-A level is not associated with an increased risk of EmCS IFC or adverse neonatal outcomes despite greater odds of low-birthweight infants and preterm birth.

Is pregnancy associated plasma protein-A (PAPP-A) a marker for adverse perinatal outcomes in preterm isolated oligohydramnios cases?

OBJECTIVE

Isolated oligohydramnios is defined as an amniotic fluid index below five centimeter with no other coexisting condition. There are still controversies about the management and pregnancy outcomes. A marker predicting these is crucial. Low pregnancy associated plasma protein-A levels were reported to be related with adverse pregnancy outcomes. We aimed to determine the role of first trimester pregnancy associated plasma protein-A for poor outcomes in preterm isolated oligohydramnios cases.

MATERIAL AND METHODS

Fifty-one patients with singleton pregnancies diagnosed as isolated oligohydramnios at 28/0-36/6 weeks of gestation and 110 gestational age matched healthy controls between January and December 2015 were included. Maternal age, gestational age at delivery, mode of delivery, indication for cesarean section, Apgar scores at first and fifth minutes, birth weight, neonatal intensive care unit admission and mortality were recorded. Pregnancy associated plasma protein-A levels were compared between groups and its role in adverse perinatal outcomes was evaluated.

RESULTS

Pregnancy associated plasma protein-A levels and pregnancy outcomes were similar in two groups (p > 0.050) except birth weight, gestational age at delivery and presence of fetal distress. Pregnancy associated plasma protein-A levels did not differ in terms of delivery mode, presence of fetal distress, first and fifth minutes Apgar scores and neonatal intensive care unit admission (p = 0.323,0.650,0.990,0.112,0.853). Also, it was not determined as a risk factor for cesarean section, presence of fetal distress, low Apgar scores and neonatal intensive care unit admission.

CONCLUSION

Pregnancy associated plasma protein-A, a well-known prognostic factor for some of high risk pregnancy conditions, may not be used as a marker in preterm isolated oligohydramnios cases.

Is there any relationship between low PAPP-A levels and measures of umbilical vein and placental thickness during first trimester of pregnancy?

OBJECTIVE

Low pregnancy-associated plasma protein A (PAPP-A) level is associated with adverse perinatal outcomes. The purpose of this study was to evaluate relationship between umbilical cord diameter (UCD), umbilical vein and artery diameters (UVD, UAD), placental thickness, and PAPP-A level at gestational age of between 11 and 14 weeks.

METHODS

UCD, UVD, UAD, and placental thickness of 246 women were assessed during ultrasound examination at between 11 and 14 weeks of gestation, as well as measurement of nuchal translucency (NT) and crown-rump length (CRL). Patients were divided into 2 groups according to PAPP-A percentile. Group 1 comprised 23 patients who had low PAPP-A (<0.44 multiple of medians [MoM], <10th percentile) and Group 2 was made up of 223 patients with PAPP-A of >0.44 MoM, >10th percentile. Calipers used for measurement were placed inner edge to inner edge of echogenic boundaries of the vessel. Largest sections of all vessels (UV and both arteries) were evaluated. Thickest part of the placenta was used for placental thickness measurement.

RESULTS

Narrow UCD (<4.5±0.6 mm) was associated with low PAPP-A level (p=0.02). There was no significant difference in UVD, UAD, or placental thickness between groups. There was no significant difference in gestational age, CRL, or NT between groups. Fetal birth weight was significantly lower in Group 1 (p=0.03).

CONCLUSION

Closer attention to women with low-risk, healthy pregnancies and low PAPP-A level in first trimester screening results is recommended. They should be routinely screened for background medical risk factors and umbilical cord morphology in first trimester scan.