Mid-trimester triple test levels in early and late onset severe pre-eclampsia

Maternal lipid levels in preeclampsia: singleton vs. twin pregnancies

OBJECTIVE

To compare the maternal lipid levels in preeclampsia (PE) patients between singleton and twin pregnancies.

METHODS

In this retrospective study, pregnant women with PE were divided into singleton group (n = 702) and twin group (n = 198). Serum lipids which include total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C) were measured and the TC/HDL-C ratio, TG/HDL-C ratio, and LDL-C/HDL-C ratio were calculated and compared between the two groups. Covariance analysis was used to correct the potential factors affecting serum lipid levels such as maternal age, pre-pregnancy body mass index, gestational weight gain, etc.

RESULTS

The levels of TC, TG, LDL-C, and TC/HDL-C ratio, TG/HDL-C ratio, LDL-C/HDL-C ratio in twin PE were significantly higher than those in singleton PE group, and there was no significant difference in the level of HDL-C between the two groups. In late-onset PE patients, the lipid levels of TC, TG, LDL-C, and TC/HDL-C ratio, TG/HDL-C ratio, LDL-C/HDL-C ratio in twin PE group were significantly higher than those in singleton PE group, with no significant difference in the level of HDL-C. However, in early-onset PE patients, there were no significant differences in the lipid levels between the two groups.

CONCLUSIONS

There were more obvious lipid disturbances such as higher levels of TC, TG, LDL-C, and TC/HDL-C ratio, TG/HDL-C ratio, LDL-C/HDL-C ratio in twin PE group than singleton PE group. The differences of lipid levels appeared mainly in late-onset PE group, while the lipid levels in twin PE group were similar to those in singleton PE group during pregnancy in early-onset PE group.

Population-based biomarker screening and the development of severe preeclampsia in California

OBJECTIVE

The purpose of this study was to examine the relationship between second-trimester maternal serum biomarkers and the development of early- and late-onset severe preeclampsia in euploid pregnancies.

STUDY DESIGN

Included were 136,139 pregnancies that obtained second-trimester prenatal screening through the California Prenatal Screening Program with live births in 2006-2008. We identified severe preeclampsia diagnoses from hospital discharge records. We used log binomial regression to examine the association between abnormal second-trimester maternal serum biomarkers and the development of severe preeclampsia.

RESULTS

Approximately 0.9% of all women (n = 1208) in our sample experienced severe preeclampsia; 329 women at <34 weeks' gestation and 879 women ≥34 weeks' gestation. High levels of alpha fetoprotein (AFP), human chorionic gonadotropin, inhibin (multiple of the median, ≥95th percentile), and low unconjugated estriol (multiple of the median, ≤5th percentile), were associated with severe preeclampsia (relative risk, 2.5-11.7). Biomarkers were more predictive of early-onset severe preeclampsia (relative risk, 3.8-11.7). One in 9.5 pregnancies with combined high AFP, inhibin, and low unconjugated estriol levels experienced severe early-onset preeclampsia compared with 1 in 680.5 pregnancies without any abnormal biomarkers.

CONCLUSION

The risk of the development of severe preeclampsia increases for women with high second-trimester AFP, human chorionic gonadotropin, inhibin, and/or low unconjugated estriol; this is especially true for early-onset severe preeclampsia. When abnormal biomarkers co-occur, risk dramatically increases. Although the screening value of second-trimester biomarkers is low, abnormal biomarkers, especially when occurring in combination, appear to indicate placental dysfunction that is associated with the development of severe preeclampsia.

Mid-trimester maternal serum HCG and alpha fetal protein levels: clinical significance and prediction of adverse pregnancy outcome

CONTEXT

Maternal serum human Chorionic Gonadotropin (hCG) and Alpha Fetal Protein (AFP) were originally introduced to detect trisomy 21 and neural tube defects. However, in the absence of aneuploidy or neural tube defects, mid-trimester maternal serum hCG and/or maternal serum AFP associated with adverse pregnancy outcomes. Pregnancies with unexplained mid-trimester elevation in maternal serum hCG and/or maternal serum AFP, are at increased risk for pregnancy complications resulting from placental insufficiency.

EVIDENCE ACQUISITION

Mid-trimester maternal serum hCG>2.5 MoM associated with an increased risk for pregnancy complications including: late fetal loss, gestational hypertension, preeclampsia, intrauterine growth restriction (IUGR), preterm delivery and intrauterine fetal death(IUFD). Mid-trimester maternal serum AFP levels >2.5 MoM are thought to reflect a defect in placentation and associated with an increased risk for pregnancy complications including: late fetal loss, gestational hypertension, preeclampsia, IUGR, preterm delivery and IUFD.

RESULTS

Combined mid-trimester elevation in maternal serum hCG and AFP levels suggest a more complex type of placental pathology. They have stronger association with pregnancy complications including: late fetal loss, gestational hypertension, preeclampsia, IUGR, preterm delivery and IUFD.

CONCLUSIONS

Mid-trimester maternal serum hCG or AFP levels alone cannot detect all pregnant women with increased risk to develop pregnancy complications. Multiparameter testing of placental function in mid-trimester (maternal serum hCG and AFP screening, uterine artery Doppler and placental morphology) may allow us to identify women with increased risk to develop severe placental insufficiency and pregnancy complications. However, future prospective studies are needed to confirm the prognostic significance of multiparameter testing of placental function in mid-trimester.

Quantitative ELISAs for serum soluble LHCGR and hCG-LHCGR complex: potential diagnostics in first trimester pregnancy screening for stillbirth, Down's syndrome, preterm delivery and preeclampsia

BACKGROUND

Soluble LH/hCG receptor (sLHCGR) released from placental explants and transfected cells can be detected in sera from pregnant women. To determine whether sLHCGR has diagnostic potential, quantitative ELISAs were developed and tested to examine the correlation between pregnancy outcome and levels of serum sLHCGR and hCG-sLHCGR complex.

METHODS

Anti-LHCGR poly- and monoclonal antibodies recognizing defined LHCGR epitopes, commerical anti-hCGbeta antibody, together with recombinant LHCGR and yoked hCGbeta-LHCGR standard calibrators were used to develop two ELISAs. These assays were employed to quantify serum sLHCGR and hCG-sLHCGR at first trimester human pregnancy.

RESULTS

Two ELISAs were developed and validated. Unlike any known biomarker, sLHCGR and hCG-sLHCGR are unique because Down's syndrome (DS), preeclampsia and preterm delivery are linked to both low (less than or equal to 5 pmol/mL), and high (equal to or greater than 170 pmol/mL) concentrations. At these cut-off values, serum hCG-sLHCGR together with PAPP-A detected additional DS pregnancies (21%) which were negative by free hCGbeta plus PAPP-A screening procedure. Therefore, sLHCGR/hCG-sLHCGR has an additive effect on the current primary biochemical screening of aneuploid pregnancies. More than 88% of pregnancies destined to end in fetal demise (stillbirth) exhibited very low serum hCG-sLHCGR(less than or equal to 5 pmol/mL) compared to controls (median 16.15 pmol/mL, n = 390). The frequency of high hCG-sLHCGR concentrations (equal to or greater than 170 pmol/mL) in pathological pregnancies was at least 3-6-fold higher than that of the control, suggesting possible modulation of the thyrotropic effect of hCG by sLHCGR.

CONCLUSIONS

Serum sLHCGR/hCG-sLHCGR together with PAPP-A, have significant potential as first trimester screening markers for predicting pathological outcomes in pregnancy.

Impact of inherited thrombophilias on first and second trimester maternal serum markers for aneuploidy

OBJECTIVE

To evaluate first and second-trimester maternal serum markers in pregnancies complicated with inherited thrombophilias.

METHODS

A case-control study was conducted in 50 pregnancies complicated with hereditary thrombophilia and 100 control pregnancies.

RESULTS

Each woman with inherited thrombophilia received low molecular weight heparin (LMWH) throughout her pregnancy. Gravidity, parity, number of first-trimester and second-trimester abortions, and rate of adverse pregnancy outcomes (APO) were significantly higher in the thrombophilia group compared to the control group (P < 0.001 for all). Among the thrombophilia group median values of pregnancy associated placental protein-A (PAPP-A) (0.6 vs. 0.9; P < 0.001) and free β-human chorionic gonadotropin (β-hCG) (0.9 vs. 1.1; P = 0.001) in the first trimester; median values of α-fetoprotein (AFP) (0.7 vs. 1.1; P = 0.027), unconjugated estriol 3 (uE3) (0.9 vs. 1.1; P < 0.001), and hCG (0.7 vs. 1.2; P < 0.001) in the second trimester were significantly lower with respect to control pregnancies. Multivariate analysis revealed that low uE3 and hCG levels were independently associated with APO.

CONCLUSION

Pregnant women with hereditary thrombophilias, all of whom were treated with LMWH, had decreased levels of all first and second trimester serum markers. In addition, levels of hCG and uE3 in the second trimester could independently predict placenta-related disorders and adverse outcomes in these patients.

Intrauterine growth restriction: new concepts in antenatal surveillance, diagnosis, and management

Intrauterine growth restriction (IUGR) remains one of the main challenges in maternity care. Improvements have to start from a better definition of IUGR, applying the concept of the fetal growth potential. Customized standards for fetal growth and birthweight improve the detection of IUGR by better distinction between physiological and pathological smallness and have led to internationally applicable norms. Such developments have resulted in new insights in the assessment of risk and surveillance during pregnancy. Serial fundal height measurement plotted on customized charts is a useful screening tool, whereas fetal biometry and Doppler flow are the mainstay for investigation and diagnosis of IUGR. Appropriate protocols based on available evidence as well as individualized clinical assessment are essential to ensure good management and timely delivery.

Obstetrical complications associated with abnormal maternal serum markers analytes

OBJECTIVE

To review the obstetrical outcomes associated with abnormally elevated or decreased level of one or more of the most frequently measured maternal serum marker analytes used in screening for aneuploidy. To provide guidance to facilitate the management of pregnancies that have abnormal levels of one of more markers and to assess the usefulness of these markers as a screening test.

OPTIONS

Perinatal outcomes associated with abnormal levels of maternal serum markers analytes are compared with the outcomes of pregnancies with normal levels of the same analytes or the general population.

EVIDENCE

The Cochrane Library and Medline were searched for English-language articles published from 1966 to February 2007, relating to maternal serum markers and perinatal outcomes. Search terms included PAPP-A (pregnancy associated plasma protein A), AFP (alphafetoprotein), hCG (human chorionic gonadotropin), estriol, unconjugated estriol, inhibin, inhibin-A, maternal serum screen, triple marker screen, quadruple screen, integrated prenatal screen, first trimester screen, and combined prenatal screen. All study types were reviewed. Randomized controlled trials were considered evidence of the highest quality, followed by cohort studies. Key individual studies on which the recommendations are based are referenced. Supporting data for each recommendation are summarized with evaluative comments and references. The evidence was evaluated using the guidelines developed by the Canadian Task Force on Preventive Health Care.

VALUES

The evidence collected was reviewed by the Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada.

BENEFITS, HARMS, AND COSTS

The benefit expected from this guideline is to facilitate early detection of potential adverse pregnancy outcomes when risks are identified at the time of a maternal serum screen. It will help further stratification of risk and provide options for pregnancy management to minimize the impact of pregnancy complications. The potential harms resulting from such practice are associated with the so called false positive (i.e., uncomplicated pregnancies labelled at increased risk for adverse perinatal outcomes), the potential stress associated with such a label, and the investigations performed for surveillance in this situation. No cost-benefit analysis is available to assess costs and savings associated with this guideline. SUMMARY STATEMENTS: 1. An unexplained level of a maternal serum marker analyte is defined as an abnormal level after confirmation of gestational age by ultrasound and exclusion of maternal, fetal, or placental causes for the abnormal level. (III) 2. Abnormally elevated levels of serum markers are associated with adverse pregnancy outcomes in twin pregnancies, after correction for the number of fetuses. Spontaneous or planned mutifetal reductions may result in abnormal elevations of serum markers. (II-2) RECOMMENDATIONS: 1. In the first trimester, an unexplained low PAPP-A (< 0.4 MoM) and/or a low hCG (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) In the second trimester, an unexplained elevation of maternal serum AFP (> 2.5 MoM), hCG (> 3.0 MoM), and/or inhibin-A (> or =2.0 MoM) or a decreased level of maternal serum AFP (< 0.25 MoM) and/or unconjugated estriol (< 0.5 MoM) are associated with an increased frequency of adverse obstetrical outcomes, and, at present, no specific protocol for treatment is available. (II-2A) 2. Pregnant woman with an unexplained elevated PAPP-A or hCG in the first trimester and an unexplained low hCG or inhibin-A and an unexplained elevated unconjugated estriol in the second trimester should receive normal antenatal care, as this pattern of analytes is not associated with adverse perinatal outcomes. (II-2A) 3. The combination of second or third trimester placenta previa and an unexplained elevated maternal serum AFP should increase the index of suspicion for placenta accreta, increta, or percreta. (II-2B) An assessment (ultrasound, MRI) of the placental-uterine interface should be performed. Abnormal invasion should be strongly suspected, and the planning of delivery location and technique should be done accordingly. (III-C) 4. A prenatal consultation with the medical genetics department is recommended for low unconjugated estriol levels (<0.3 MoM), as this analyte pattern can be associated with genetic conditions. (II-2B) 5. The clinical management protocol for identification of potential adverse obstetrical outcomes should be guided by one or more abnormal maternal serum marker analyte value rather than the false positive screening results for the trisomy 21 and/or the trisomy 18 screen. (II-2B) 6. Pregnant woman who are undergoing renal dialysis or who have had a renal transplant should be offered maternal serum screening, but interpretation of the result is difficult as the level of serum hCG is not reliable. (II-2A) 7. Abnormal maternal uterine artery Doppler in association with elevated maternal serum AFP, hCG, or inhibin-A or decreased PAPP-A identifies a group of women at greater risk of IUGR and gestational hypertension with proteinuria. Uterine artery Doppler measurements may be used in the evaluation of an unexplained abnormal level of either of these markers. (II-2B) 8. Further research is recommended to identify the best protocol for pregnancy management and surveillance in women identified at increased risk of adverse pregnancy outcomes based on an abnormality of a maternal serum screening analyte. (III-A) 9. In the absence of evidence supporting any specific surveillance protocol, an obstetrician should be consulted in order to establish a fetal surveillance plan specific to the increased obstetrical risks (maternal and fetal) identified. This plan may include enhanced patient education on signs and symptoms of the most common complications, increased frequency of antenatal visits, increased ultrasound (fetal growth, amniotic fluid levels), and fetal surveillance (biophysical profile, arterial and venous Doppler), and cervical length assessment. (III-A) 10. Limited information suggests that, in women with elevated hCG in the second trimester and/or abnormal uterine artery Doppler (at 22-24 weeks), low-dose aspirin (60-81 mg daily) is associated with higher birthweight and lower incidence of gestational hypertension with proteinuria. This therapy may be used in women who are at risk. (II-2B) 11. Further studies are recommended in order to assess the benefits of low-dose aspirin, low molecular weight heparin, or other therapeutic options in pregnancies determined to be at increased risk on the basis of an abnormal maternal serum screening analyte. (III-A) 12. Multiple maternal serum markers screening should not be used at present as a population-based screening method for adverse pregnancy outcomes (such as preeclampsia, placental abruption, and stillbirth) outside an established research protocol, as sensitivity is low, false positive rates are high, and no management protocol has been shown to clearly improve outcomes. (II-2D) When maternal serum screening is performed for the usual clinical indication (fetal aneuploidy and/or neural tube defect), abnormal analyte results can be utilized for the identification of pregnancies at risk and to direct their clinical management. (II-2B) Further studies are recommended to determine the optimal screening method for poor maternal and/or perinatal outcomes. (III-A).

Down syndrome biochemical markers and screening for preeclampsia at first and second trimester: correlation with the week of onset and the severity

OBJECTIVES

To estimate the combined screening performance of first and early second trimester prenatal serum markers for Down syndrome, in screening for the development of preeclampsia, and analyze the correlation among marker levels, week of onset, and severity of the disease.

METHODS

A retrospective cohort study was carried out on 32 women with preeclampsia and 3044 controls. Serum samples from these pregnancies were assayed for pregnancy-associated plasma protein-A (PAPP-A), alpha-fetoprotein (AFP), unconjugated estriol (uE3), human chorionic gonadotrophin (hCG), and inhibin-A. A likelihood ratio and the odds of being affected given a positive result (OAPR) of various combinations of markers were calculated and receiver operating characteristic (ROC) curves analysis was performed.

RESULTS

In the pregnancies that subsequently developed preeclampsia, first trimester PAPP-A concentration was significantly lower and concentrations of early second trimester inhibin-A and hCG significantly elevated. Levels of early second trimester uE3 and AFP were not significantly altered. We also found that inhibin-A correlates with both onset of the disease and the severity.

CONCLUSION

Down syndrome biochemical markers levels are altered in those patients who subsequently developed preeclampsia and may be a useful screening test for preeclampsia. Inhibin-A is the most predictive marker and correlates with the severity of subsequent preeclampsia and inversely with the week of occurrence of preeclampsia.

[Mirror pre-eclampsia: Ballantyne's syndrome. Two cases]

We report two cases of Ballantyne's syndrome which was first described in association with foeto-placental hydrops caused by rhesus isoimmunization. Our two cases occurred in association with materno-fetal parvovirus infection. Although the pathogenic mechanism remains to be fully elucidated, fluid retention and hyperplacentation are the main features. Together with these two case reports, a literature review confirmed the diverse nonimmunological etiologies associated with Ballantyne's syndrome. Clinicians should be aware of this particular presentation of hydrops fetalis resulting from a mechanism different from hypotrophic placentation because specific etiological treatment can avoid unnecessary pregnancy termination. Pre-conception counselling is also different.

Human chorionic gonadotropin levels between 16 and 21 weeks of pregnancy and prediction of pre-eclampsia

OBJECTIVE

To determine whether levels of beta human choriogonadotropin (beta-hCG) during the second trimester are a predictor of pre-eclampsia.

METHODS

A prospective study of 784 women was conducted between their 16th and 20th week of pregnancy. Primigravidas and multigravidas were analyzed separately, and the cutoff point was determined using a receiver operating characteristic curve. The accuracy of beta-hCG levels in the prediction of pre-eclampsia was evaluated. The likelihood ratios were calculated for different levels of beta-hCG in both groups.

RESULTS

Pre-eclampsia prevalence was 7.1% among primigravidas and 4.6% among multigravidas. The cutoff concentration was 2.0 MoM in both groups. For primigravidas and multigravidas, respectively, the area below the curve was 0.96 and 0.95; sensitivity was 88.5% and 100%; specificity was 92.0% and 85.6%; positive predictive value was 0.46 and 0.25; and negative predictive value was 0.99 and 1.0. With a cutoff concentration of 2.0 MoM of beta-hCG, the positive likelihood ratio was 11.1 in primigravidas and 6.9 in multigravidas.

CONCLUSION

This study shows that measuring levels of beta-hCG during the second trimester of pregnancy is useful in clinical practice to identify pregnant women who will develop pre-eclampsia.

Midtrimester triple test levels in women with severe preeclampsia and HELLP syndrome

BACKGROUND

The levels of midtrimester triple test constituents are known to be altered in hypertensive disorders of pregnancy.

OBJECTIVE

Our aim was to determine whether midtrimester triple test constituent levels differ in women with severe preeclampsia and those who also develop HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome.

METHODS

A retrospective chart analysis of 106 women with severe preeclampsia for whom midtrimester triple test data were available was made. None of these patients had fetuses with abnormal karyotype, nor did they deliver infants with malformations. The levels of midtrimester maternal serum alpha-fetoprotein (MSAFP), human chorionic gonadotropin (MShCG) and unconjugated estriol (MSuE3) of 74 patients with severe preeclampsia were compared with those of 32 patients who also developed HELLP syndrome.

RESULTS

The mean MShCG was significantly higher and the mean MSuE3 was significantly lower in patients with HELLP syndrome than in those with only severe preeclampsia [1.78 multiple of the medians (MoM), standard error (SE) 0.18 vs. 1.27 MoM, SE 0.07, p=0.015 and 0.86 MoM, SE 0.05 vs. 1.04 MoM, SE 0.07; p = 0.03, respectively]. The two groups did not differ significantly with regard to MSAFP levels.

CONCLUSION

Unexplained high levels of midtrimester MShCG and low levels of MSuE3 may be associated with the development of HELLP syndrome in women with severe preeclampsia.