Association between human chorionic gonadotropin (hCG) levels and adverse pregnancy outcomes: A systematic review and meta-analysis

Human chorionic gonadotropin (hCG), a glycoprotein produced in the placenta, is crucial for a healthy pregnancy. We investigated the relationship between hCG levels and adverse pregnancy outcomes. We conducted a systematic review including studies measuring hCG blood levels in the first or second trimester, reporting on any of the 12 predefined adverse pregnancy outcomes with logistic regression-adjusted association estimates. The primary outcomes were placenta-associated complications, such as miscarriage, preeclampsia, intrauterine growth restriction, and preterm delivery. We searched PubMed, Embase and CINAHL Complete. The hCG levels were analysed as multiple of the median (MoM). Odds ratio (OR) and 95% confidence interval (CI) were used. Risk of bias and the certainty of evidence were assessed using ROBINS-I and GRADE, respectively. Meta-analysis also showed that hCG levels, reported as MoM ≥2/2.31/2.5, might be associated with an increased risk of preeclampsia (OR 2.08, 95% CI 1.26 to 3.44) and preterm delivery (OR 1.29, 95% CI 1.12 to 1.47), but the evidence is very uncertain. High second trimester hCG levels may be associated with preeclampsia and preterm delivery but confidence in evidence is low.

Recurrence Rate for Isolated Elevated Maternal Serum Alpha-Fetoprotein Levels and Pregnancy Outcomes

Objective: To examine the rate of recurrence for elevated isolated maternal serum alpha-fetoprotein (MSAFP) and its associated adverse outcomes during a subsequent pregnancy. Materials and Methods: A retrospective cohort study of pregnant multiparous women who had elevated MSAFP levels during an initial and a subsequent pregnancy between 1994 and 2020. Results: Twenty-seven out of 344 (7.8%) women with elevated MSAFP had recurrent elevated MSAFP in a subsequent pregnancy. Four women were excluded due to missing data. Of the 23 women included, 5 (22%) had fetal growth restriction (FGR), 2 (9%) had pre-eclampsia, 9 (35%) had preterm births, and 2 (9%) had fetal death/miscarriage in their subsequent pregnancy. Looking at individual outcomes, 60% of women had recurrence of preterm labor, 33% had recurrence of fetal death, and 25% had recurrence of FGR. Conclusion: Women with elevated MSAFP levels during an initial pregnancy should be informed during preconception counseling about their risk of recurring elevated MSAFP and its associated adverse outcomes risks.

Maternal Serum Inhibin-A Augments the Value of Maternal Serum PlGF and of sFlt-1/PlGF Ratio in the Prediction of Preeclampsia and/or FGR Near Delivery—A Secondary Analysis

Objective: We previously provided evidence to confirm that maternal serum levels of soluble Fms-like tyrosine kinase-1 (sFlt-1), placental growth factor (PlGF), and their ratio are useful tools to direct the management of preeclampsia (PE), fetal growth restriction (FGR), and PE+FGR near delivery. In this secondary analysis, we further examine the potential additive value of maternal serum Inhibin-A, which is a hormone marker of the transforming growth factor family, to the accuracy provided by maternal serum PlGF and sFlt-1. Methods: We conducted a secondary analysis where we extracted the data of a cohort of 125 pregnant women enrolled near delivery at the clinics of the University Medical Center of Ljubljana, Slovenia. The dataset included 31 cases of PE, 16 of FGR, 42 of PE+FGR, 15 preterm delivery (PTD), and 21 unaffected controls with delivery of a healthy baby at term. Cases delivered before 34 weeks’ gestation included 10 of PE, 12 of FGR, 28 of PE+FGR, and 6 of PTD. In addition to the recorded demographic characteristics and medical history and the maternal serum levels of PlGF and sFlt-1/PlGF ratio, which were previously published, we evaluated the added value of maternal serum Inhibin-A. The predictive accuracy of each biomarker, their ratios, and combinations were estimated from areas under the curve (AUC) of receiver operating characteristics (ROC) curves, Box and Whisker plots, and by multiple regression. We estimated accuracy by the continuous marker model and a cutoff model. Results: In this study, we combined Inhibin-A with PlGF or with the sFlt-1/PlGF ratio and showed a 10–20% increase in AUCs and 15–45% increase in the detection rate, at 10% false positive rate, of PE, and a lower, but significant, increase for PE+FGR and FGR in all cases but not for FGR in early cases delivered < 34 weeks. The use of a cutoff model was adequate, although a bit higher accuracy was obtained from the continuous model. The highest correlation was found for PlGF with all three complications. Conclusion: In this secondary analysis, we have found that maternal serum Inhibin-A improves the accuracy of predicting PE and PE+FGR provided by maternal serum angiogenic markers alone, bringing the results to a diagnostic level; thus, it could be considered for directing clinical management. Inhibin-A had smaller or no added value for the accuracy of predicting FGR alone, mainly of early cases delivered <34 weeks.

Raised neutrophil lymphocyte ratio and serum beta hCG level in early second trimester of pregnancy as predictors for development and severity of preeclampsia

Early detection and prediction of preeclampsia (PE) may avert serious materno-fetal complications. This prospective nested study was conducted to evaluate the role of serum beta human chorionic gonadotropin (hCG) and the neutrophil-lymphocyte ratio (NLR) in predicting the development and severity of PE. Four hundred and forty primigravidas, between 16 to 18 weeks of gestation, were recruited in the study. Serum beta-hCG and NLR were measured at the time of recruitment and they were followed and monitored for the development of PE and severe PE. Out of these 440 women, 64 (14%) developed PE; of which 25 (39%) developed severe PE. The mean values of NLR and serum beta hCG were significantly higher in patients developing PE and severe PE. NLR, with a cutoff value of 5.6, predicted the development of PE with 73.4% sensitivity and 88.6% specificity and severe PE with sensitivity 93.3% and specificity 86.6% respectively. The sensitivity and specificity of serum beta hCG in predicting the development of PE was 75% each for a cutoff value of 25,415 IU/mL whereas these values were 86.7%, and 79.1% respectively, for a cut-off value of 29,654 IU/mL for predicting the development of severe PE. These findings suggest that NLR and serum beta hCG can be used as excellent biomarkers in predicting both the development of PE and its severity. Multicentric studies involving subjects of multiple ethnicities should be done for establishing its utility as a routine screening test.

Screening for pre-eclampsia by using maternal serum inhibin A, activin A, human chorionic gonadotropin, unconjugated estriol, and alpha-fetoprotein levels and uterine artery Doppler in the second trimester of pregnancy

AIMS

To analyse the predictive power of maternal serum inhibin A, activin A, human chorionic gonadotropin (hCG), unconjugated estriol (uE(3)), alpha-fetoprotein (AFP) levels and uterine artery Doppler in the second trimester of pregnancy in screening for pre-eclampsia.

METHODS

Maternal serum inhibin A, activin A, hCG, uE(3), and AFP levels and uterine artery Doppler were determined in 178 healthy, pregnant women in the second trimester of pregnancy. Serum samples were collected between the 16th and 18th weeks of gestation, and Doppler investigation was performed between the 24th and 26th weeks of gestation. Receiver operating characteristic curves were created to analyse the predictive powers of the above parameters in screening for pre-eclampsia. Different combinations also were analysed.

RESULTS

The rate of pre-eclampsia was 7.9% (14/178). Maternal serum inhibin A, activin A, hCG, AFP levels, the rate of presence of the prediastolic notch and uterine artery resistance index (RI) values in pre-eclamptic pregnancies were significantly higher than those in healthy pregnancies. Presence of the prediastolic notch, uterine artery RI, maternal serum activin A and inhibin A levels had high predictive efficacy, and each had a sensitivity between 70 and 93% and a specificity between 87% and 98%. The addition of inhibin A or activin A measurement to the Doppler velocimetry improved the specificity to 99-100%.

CONCLUSIONS

Maternal serum inhibin A and activin A levels and uterine artery Doppler appear to be useful screening tests during the second trimester for pre-eclampsia. However, addition of these hormonal markers to Doppler velocimetry only slightly improves the predictive efficacy, which appears clinically insignificant.