Clinical Importance of Low Level of PAPP-A in First Trimester of Pregnancy - An Obstetrical Dilemma in Chromosomally Normal Fetus

Evaluation of the Relationship between Pregnancy-Associated Plasma Protein A (PAPP-A) and Pregnancy Outcomes

Background

In the current study, we aimed to evaluate the association between pregnancy-related plasma protein-A (PAPP-A) levels measured in the first trimester and pregnancy outcomes.

Materials and Methods

This is a descriptive-analytical study that was performed in 2019--2021 on 1061 pregnant women in their first trimester. Demographic and basic information of all women were collected. These data included age, weight, parity, and date of delivery. Then the quantity of PAPP-A was recorded in three groups including less than 0.5 MOM, 0.5 to 2.5 MOM, and more than 2.5 MOM.

Results

Data of 1061 women were analyzed. 900 women (84.8%) had term delivery and 155 women (14.6%) had pre-term deliveries. PAPP-A levels were normal in 83.4% of women. BMI and number of pregnancies had significant relationships with PAPP-A (p < 0.001, P = 0.03 respectively). The mean BMI in mothers with PAPP-A higher than 2.5 was significantly more than mothers with normal or lower PAPP-A levels (26.2 ± 31, P = 0.04). The frequency of term labor in mothers with normal PAPP-A was higher than other mothers (86.3%, P = 0.04). The frequency of preeclampsia in recent pregnancies in mothers with normal PAPP-A was significantly lower than other mothers (p < 0.001) and the frequency of abortions in recent pregnancies in mothers with PAPP-A less than 0.5 was significantly higher than mothers with normal or elevated PAPP-A (p < 0.001).

Conclusion

Mothers with low PAPP-A levels are more likely to have poor pregnancy outcomes such as abortion, pre-term labor, and preeclampsia.

Clinical Application of a Multiparameter-Based Nomogram Model in Predicting Preeclampsia

Based on single-center data, the related predictive factors of preeclampsia (PE) were investigated, and a nomogram prediction model was established and validated. A retrospective collection of 93 PE patients admitted to our hospital from January 2019 to January 2021 were included in the PE group. In addition, non-PE pregnant women were selected for physical examination during the same period for matching, and 170 normal pregnant women who met the matching conditions were found as the normal pregnancy group. Clinical data of the selected candidates were collected. The risk factors of PE were screened by logistic regression analysis, and the lipopograph prediction model was constructed and verified. Logistic analysis results showed that age (OR = 3.069, 95% CI = 1.233-7.638), prepregnancy BMI (OR = 2.896, 95% CI = 1.193-7.029), vitamin E deficiency (OR = 2.803, 95% CI = 1.134-6.928), 25-(OH)D (OR = 0.944, 95% CI = 0.903∼9.988), PLGF (OR = 0.887, 95% CI = 0.851∼0.924), PAPP-A (OR = 1.240, 95% CI = 1.131∼1.360), and PI (OR = 6.376, 95% CI = 1.163∼34.967) were the independent risk factors for PE prediction (P < 0.05). The ROC curve showed that the AUC of the model for predicting the risk of PE was 0.957 (95% CI: 0.935-0.979), and the specificity and sensitivity were 0.912 and 0.892, respectively. H-L goodness of the fit test showed that there was no statistical significance in the deviation between the actual observed value and the predicted value of the risk in the line graph model (χ 2 = 7.001, P=0.536). The bootstrap test was used for internal verification, and the original data were repeatedly sampled 1000 times. The average absolute error of the calibration curve is 0.014, and the fitting degree between the calibration curve and the ideal curve is good. Age, prepregnancy BMI, lack of vitamin E, 25-(OH)D, PLGF, PAPP-A, and PI are independent risk factors for predicting PE. The establishment of a nomogram prediction model based on the above parameters can help identify PE high-risk groups in the early clinical stage and provide a reference for individualized clinical diagnosis and treatment.

Relationship between extreme values of first trimester maternal pregnancy associated plasma Protein-A, free-β-human chorionic gonadotropin, nuchal translucency and adverse pregnancy outcomes

OBJECTIVE

The aim of our study was to investigate the relationship between extreme values of first trimester screening markers and adverse obstetric outcomes.

MATERIALS AND METHODS

Our study was conducted by examining the prenatal and postnatal perinatal records of 786 singleton gestations between the ages of 18-40, who applied to Prof. Dr. Cemil Taşçıoğlu City Hospital outpatient clinics for first-trimester screening for aneuploidy, between January 1, 2017 and December 31, 2019.

RESULTS

The presence of small for gestational age (SGA) was found to be statistically significant for the <5 percentile (<0.37) pregnancy-associated plasma protein A (PAPP-A) group (p = 0.016). For <5 percentile β-hCG group, the presence of gestational diabetes mellitus (GDM), premature rupture of membrane (PROM) and preterm premature rupture of membrane (PPROM) was determined as a statistically significant risk (p = 0.015, p = 0.005, p = 0.02 respectively) In the univariate test, fetal death rate was found to be high for ≥90 percentile at nuchal translucency (NT), but the presence of fetal death was found to be statistically insignificant in logistic regression analysis. (p: 0.057).

CONCLUSION

First trimester screening test can be used in predicting pregnancy complications. In this study we found that serum levels of PAPP-A are associated with developing SGA, while GDM, PROM and PPROM are more common in low serum free β-hCG.

The expression of pregnancy-associated plasma protein-A (PAPP-A) in human blastocoel fluid-conditioned media: a proof of concept study

Purpose

The aim of this study was to determine if pregnancy-associated plasma protein-A (PAPP-A), typically measured in maternal serum and a potential predictor of adverse maternal and fetal outcomes such as spontaneous miscarriage, pre-eclampsia, and stillbirth, is expressed in blastocoel fluid–conditioned media (BFCM) at the embryonic blastocyst stage.

Design

This is an in vitro study.

Methods

BFCM samples from trophectoderm-tested euploid blastocysts (n = 80) from in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) patients were analyzed for PAPP-A mRNA. BFCM was obtained from blastocyst stage embryos in 20 uL drops. Blastocysts underwent trophectoderm biopsy for preimplantation genetic testing for aneuploidy prior to blastocyst vitrification and BFCM collection for snap freezing. cfDNA was synthesized using BFCM collected from 80 individual euploid blastocysts. Next, real-time qPCR was performed to detect expression of PAPP-A with GAPDH for normalization of expression in each sample.

Results

PAPP-A mRNA was detected in 45 of 80 BFCM samples (56.3%), with varying levels of expression across samples.

Conclusion

Our study demonstrates the expression of PAPP-A in BFCM. To our knowledge, this is the first study to report detection of PAPP-A mRNA in BFCM. Further studies are required and underway to investigate a greater number of BFCM samples as well as the possible correlation of PAPP-A expression with pregnancy outcomes of transferred euploid blastocysts. If found to predict IVF and obstetric outcomes, PAPP-A may provide additional information along with embryonic euploidy for the selection of the optimal blastocyst for embryo transfer.

The association between first trimester placental biomarkers and placental lesions of maternal vascular malperfusion

INTRODUCTION

Abnormal levels of first trimester placental biomarkers are associated with the development of placental syndrome (PS). However, prediction performance is moderate, possibly explained by the clinical heterogeneity of PS. Aim of this study is to investigate the association between first trimester biomarkers and the presence of maternal vascular malperfusion (MVM), as a marker for placental insufficiency.

METHODS

This retrospective study included 195 women with available first trimester blood sample and placenta histological sections for examination at the Maastricht University Medical Centre. Women were divided into 4 groups, based on the presence of having MVM lesions and/or PS. Levels of PAPP-A, PlGF and sFlt-1 were measured and MVM lesions were classified according to the Amsterdam Placental Workshop Group Consensus Statement.

RESULTS

MVM occurrence was observed in 32% of the uncomplicated pregnancies. Women with MVM (regardless of the PS) had lower levels of PAPP-A (p = 0.038) and sFLt-1 (p = 0.006), and a non-significant trend for lower PlGF and sFlt-1/PlGF ratio compared to women without MVM. Low PAPP-A levels individually and in combination with the presence of PS was significantly associated with MVM lesions (aOR = 3.0 and 6.1, respectively), as did the combination of low PlGF levels and PS (aOR = 4.6). In women with PS, having MVM increased the incidence of fetal growth restriction, small for gestational age neonates, lower birthweight and adverse neonatal outcome.

DISCUSSION

Our findings suggest that MVM lesions were found to be associated with increased obstetric risks due to early placental dysfunction that can potentially be predicted by the use of first trimester biomarkers.

The Multi-Faced Role of PAPP-A in Post-Partum Breast Cancer: IGF-Signaling is Only the Beginning

Insulin-like growth factor (IGF) signaling and control of local bioavailability of free IGF by the IGF binding proteins (IGFBP) are important regulators of both mammary development and breast cancer. A recent genome-wide association study (GWAS) identified small nucleotide polymorphisms that reduce the expression of IGFBP-5 as a risk factor of developing breast cancer. This observation suggests that genetic alterations leading to a decreased level of IGFBP-5 may also contribute to breast cancer. In the current review, we focus on Pregnancy-Associated Plasma Protein A (PAPP-A), a protease involved in the degradation of IGFBP-5. PAPP-A is overexpressed in the majority of breast cancers but its role in cancer has only begun to be explored. More specifically, this review aims at highlighting the role of post-partum involution in the oncogenic function of PAPP-A. Notably, we summarize recent studies indicating that PAPP-A plays a role not only in the degradation of IGFBP-5 but also in the deposition of collagen and activation of the collagen receptor discoidin 2 (DDR2) during post-partum involution. Finally, considering the immunosuppressive microenvironment of post-partum involution, we also discuss the unexpected finding made in Ewing Sarcoma that PAPP-A plays a role in immune evasion. While the immunosuppressive role of PAPP-A in breast cancer remains to be determined, collectively these studies highlight the multifaced role of PAPP-A in cancer that extends well beyond its effect on IGF-signaling.