Variation of Papp-A Level in the First Trimester of Pregnancy and Its Clinical Outcome

Abstract

Introduction Abnormalities in maternal serum marker levels and fetal measurements obtained during the first trimester screening can be a marker not only for certain chromosomal disorders and anomalies in the fetus but also for specific pregnancy complications. In particular, low maternal serum pregnancy-associated plasma protein-A (PAPP-A), at 11-13 weeks of gestation, is associated with stillbirth, infant death, intrauterine growth restriction, preterm birth, and pre-eclampsia in chromosomally normal fetuses, while a raised nuchal translucency is associated with specific structural abnormalities and genetic syndromes. We have studied the serum Papp-A level in 560 pregnant patients (11-13 weeks gestation) registered at Bharati Hospital and Research Centre, Pune. All patients undergoing testing were followed till the delivery and their neonatal outcome was also taken into consideration. Aims and Objectives Our aim is to study the pregnancy outcome in relation to the variations of Papp-A level in the first trimester of pregnancy. Materials and MethodsEvery patient visiting the antenatal OPD was counseled for testing of First Trimester Screening to assess fetal well-being. Patients who were registered for delivery at our hospital were taken into the trial. Blood samples were taken at 11-13 weeks of pregnancy and sent to the PerkinElmer lab for analysis. Results were expressed in Multiple of Median and patients having MOM value less than 0.5 were carefully observed till the delivery, and a thorough neonatal examination was done by a pediatrician. Observations 524 patients were included in the trial out of which 452 patients were found to have a normal Papp-A level of [0.5 MOM. All these patients were followed further during the antenatal period where 18 patients developed preterm labor and few patients developed pregnancy-induced hypertension. The obstetric outcome of patients with a normal Papp-A level was fairly uneventful as compared to others with a low Papp-A level. Conclusions Though Papp-A level in the first trimester of pregnancy (11-13 weeks) is an important predictor of future obstetric outcome, it has poor positive predictive value. Patients having a Papp-A level less than 0.5 MOM have a high risk for preterm delivery, fetal growth restriction, and stillbirths along with increased incidence of hypertensive disorders of pregnancy. A low Papp-A level is a useful indicator of risk of preterm delivery and future chance of development of pregnancy-induced hypertension.

Low maternal pregnancy‐associated plasma protein A during the first trimester of pregnancy and pregnancy outcomes

“…Stillbirth was recorded in nine pregnancies in the low PAPP‐A cohort, compared with none in the control cohort. These findings are in line with the results of earlier studies . Conversely, normal PAPP‐A levels appeared to be an early marker of normal karyotype, normal fetal growth, and favorable pregnancy outcomes.…”

“…It is anticipated that, in this group of women, pregnancy outcomes would be less favorable compared with women with PAPP‐A levels closer to 1 MoM but would be considerably better compared with women with PAPP‐A levels below 0.3 MoM. It is expected that this would include most outcomes of interest, including aneuploidy, spontaneous abortion, preterm delivery, pre‐eclampsia, and SGA neonates …”

“…These findings are in line with the results of earlier studies. 13,15,19,20 Conversely, normal PAPP-A levels appeared to be an early marker of normal karyotype, normal fetal growth, and favorable pregnancy outcomes.…”

“…However, the value of PAPP-A as an individual marker is debated and different cut-off values for low PAPP-A have been investigated in previous studies. [13][14][15][16] The aim of the present study was to estimate the clinical significance of low PAPP-A in a routinely screened population at the Helsinki University district area.…”

Maternal Serum Aneuploidy Screen and Adverse Pregnancy Outcomes

“…Dane et al [3] similarly reported PAPP-A to be a predictor of PT delivery in normotensive pregnancies. A significant inverse association between maternal serum PAAP-A and the risk of LBW but not with free beta hCG was reported by others [4][5][6].…”