The significance of mitochondrial haplogroups in preeclampsia risk.

OBJECTIVE: To determine whether mitochondrial haplogroups function as disease-modifiers or as susceptibility factors in preeclampsia using a traditional haplogroup association model. METHODS: This retrospective study haplotyped 235 control and 78 preeclamptic pregnancies from Denmark using either real-time PCR or Sanger sequencing depending on the rarity of the haplogroup. RESULTS: No significant association between haplogroups and the risk of preeclampsia was found, nor was any role for haplogroups in disease severity uncovered. CONCLUSION: Mitochondrial haplogroups are not associated with preeclampsia or the severity of preeclampsia in the Danish population. However, this study cannot exclude a role for less common mtDNA variation. Models that can examine these should be applied in preeclamptic patients.

Placental protein-13 (PP13) in combination with PAPP-A and free leptin index (fLI) in first trimester maternal serum screening for severe and early preeclampsia.

BACKGROUND: Placental protein-13 (PP13) is involved in placental invasion and has been suggested as a maternal serum marker of preeclampsia (PE) development. However, the discriminatory ability of PP13 in first trimester has not been completely clarified. METHODS: PP13 was measured in first trimester (week 10+3-13+6) maternal serum from 120 PE pregnancies and 267 control pregnancies and was correlated with clinical parameters. The population screening performance of PP13 in combination with the PE markers pregnancy associated plasma protein A (PAPPA) and free leptin index (fLI) was assessed by Monte Carlo simulation. RESULTS: In severe PE (including HELLP) cases (n=26) the median PP13 concentration was 35.8 pg/mL (range: 17.8-85.5 pg/mL) and in PE pregnancies (n=10) with birth prior to week 34, the median PP13 concentration was 30.6 pg/mL (13.1-50.1 pg/mL), compared to controls with a median of 54.8 pg/mL (range: 15.4-142.6 pg/mL) (p<0.04). The population screening detection rate (DR) for a false-positive rate of 10% for severe PE and HELLP was 26% for PP13, 28% for PP13+PAPP-A, 33% for PP13+fLI, and 40% for PP13+PAPP-A+fLI. CONCLUSIONS: PP13 is a marker of severe PE and HELLP syndrome. The screening performance of PP13 can be markedly improved by combining it with fLI and PAPP-A.

Maternal Serum Resistin Is Reduced in First Trimester Preeclampsia Pregnancies and Is a Marker of Clinical Severity.

OBJECTIVE: To examine whether resistin levels in first trimester maternal serum are associated with insulin resistance or preeclampsia (PE). METHODS: A case-control study of maternal serum resistin concentration conducted using 285 normal pregnancies and 123 PE pregnancies matched for gestational age, parity and maternal age. Samples were taken in gestational weeks 10+0-13+6. RESULTS: There was a negative correlation between resistin and clinical severity of PE, but no correlation with IS, TNF-α, body mass index, birth weight and pregnancy length. CONCLUSIONS: Resistin is reduced in first trimester of PE pregnancies, particularly in severe PE. Inflammation and IS cannot explain this phenomenon.

Polymorphisms in the tumor necrosis factor alpha and interleukin 1-beta promoters with possible gene regulatory functions increase the risk of preterm birth.

OBJECTIVE: To investigate the relation between 19 selected single nucleotide polymorphisms in three cytokine genes, tumor necrosis factor alpha (TNFA), interleukin 1-beta (IL1B) and interleukin 6 (IL6) and preterm birth (<37 weeks' gestation). DESIGN: Case-control association study. SAMPLE: A total of 117 singleton pregnant Danish Caucasian women, including 62 preterm birth cases and 55 controls (birth>or=37 weeks). METHODS: Genotyping was performed using TaqMan probes and traditional sequencing. Descriptive statistics were carried out with Fisher's exact test and Wilcoxon rank-sum test. All genetic data were tested for Hardy-Weinberg equilibrium and analyzed using logistic regression, 2x2 proportions or chi(2). Haplotypes were estimated for each gene and permutation used for association testing. RESULTS: Women carrying the TNFA -857 C>T rare allele (T) and those homozygous for the IL1B -31 T>C and IL1B -511 C>T rare alleles (C and T) have an increased risk of preterm birth with OR 3.1 (95% CI: 1.0-10.3) and OR 6.4 (95% CI: 1.3-60.5), respectively. Two estimated TNFA haplotypes were associated with preterm birth with OR 3.1 (p=0.037) and OR 2.7 (p=0.045). CONCLUSION: Polymorphisms in the cytokine genes TNFA and IL1B may increase the risk of preterm birth, possibly by a dysregulation of the immune system in pregnancy.

Early fetal size and growth as predictors of adverse outcome.

OBJECTIVE: To evaluate the association between fetal size and growth between the first and second trimesters and subsequent adverse pregnancy outcome. METHODS: A cohort was created of 7,642 singleton pregnancies cared for in three obstetric units associated with Copenhagen University. Data were obtained from ultrasound measurements at 11-14 weeks (crown-rump length, biparietal diameter) and 17-21 weeks (biparietal diameter). Fetal size was assessed by gestation-specific z scores, and fetal growth between the first and second trimester was calculated individually using conditional centiles. The main outcome measures were preterm delivery, smallness for gestational age, and perinatal death. RESULTS: Slow growth of the biparietal diameter less than the 10th and less than the 2.5th conditional centiles between first and second trimesters occurred in 10.4% and 3.6% of the population, respectively. Biparietal diameter growth less than the 10th centile was associated with perinatal death before 34 weeks (risk 0.5% compared with 0.04%, odds ratio [OR] 16.0, confidence interval [CI] 2.9-88.7). Biparietal diameter growth less than the 2.5th centile was the best predictor of perinatal death at any gestation, with a positive likelihood ratio of 4.7 and an OR of 7.3 (CI 2.4-22.2). In contrast, the biparietal diameter, dated by crown-rump length, did not have an increased risk of perinatal death; however, there was a mildly increased risk of small for gestational age birth weight (less than the 10th customized centile) if the biparietal diameter was below the 10th centile in the first trimester (risk 17% compared with 12%, OR 1.5, CI 1.2-1.8) or in the second trimester (risk 15.8% compared with 12.4%, OR 1.3, CI 1.1-1.5). CONCLUSION: Slow growth of the fetal biparietal diameter between the first and second trimesters of pregnancy is a strong predictor of perinatal death before 34 weeks.

[Prenatal diagnosis of congenital insulin-resistant diabetes (Donohue's syndrome)]. / Praenatal diagnostik for kongenit insulinresistent diabetes (Donohues syndrom).

A consanguineous Turkish couple was expecting their third child. Two years earlier their second child had died from a severe form of insulin-resistant diabetes causing Donohue's syndrome. A novel mutation (V335) in the insulin receptor gene was found to be disrupting the structure and function of the receptor. The parents, as well as their first child, were asymptomatic, heterozygous carriers. The family received genetic counselling, and chorion villus sampling was performed early in pregnancy. Genotyping showed that the child in utero was heterozygous for the mutation. Subsequently the mother gave birth to a healthy boy.

Nuchal translucency measurements are highly correlated in both mono- and dichorionic twin pairs.

OBJECTIVES: To establish the distribution of serological and ultrasound first-trimester Down syndrome markers in twins and identify correlations of significance for risk calculation. METHODS: Nuchal translucency (NT), PAPP-A and betahCG data were extracted from 181 twin pregnancies (31 mono- and 150 dichorionic) with a normal outcome. All pregnancies were consecutively and prospectively included and examined in the Copenhagen First-Trimester Study. The variance of the sum and the difference of log MoM NT values in twin pairs was used to calculate the correlation. RESULTS: The serological markers did not correlate and were nearly twice the value seen in singleton pregnancies with a median PAPP-A MoM of 2.14 and a median free betahCG MoM of 2.06. Chorionicity was not found to influence the level of biochemical markers. In all twin pairs (r = 0.343, p < 0.001, F-test), as well as mono- (r = 0.404, p = 0.011, F-test) and dichorionic twins (r = 0.316, p < 0.001, F-test) there was a significant correlation between log MoM NT in each pair. CONCLUSION: As the NT values of fetuses in subsequent pregnancies from the same woman do not correlate, the correlation between NTs in twins reflects that the NT is influenced by placental and maternal factors specific for the particular pregnancy, for example, nutrient supply or vascularisation. The correlation may be useful to improve the precision of the prenatal risk assessment for Down syndrome in first-trimester twin pregnancies. The serological markers were elevated in the examined twins as previously described.

Reduction of the disintegrin and metalloprotease ADAM12 in preeclampsia.

OBJECTIVES: The secreted form of ADAM12 is a metalloprotease that may be involved in placental and fetal growth. We examined whether the concentration of ADAM12 in first-trimester maternal serum could be used as a marker for preeclampsia. METHODS: We developed a semiautomated, time-resolved, immunofluorometric assay for the quantification of ADAM12 in serum. The assay detected ADAM12 in a range of 78-1248 microg/L. Serum samples derived from women in the first trimester of a normal pregnancy (n = 324) and from women who later developed preeclampsia during pregnancy (n = 160) were obtained from the First Trimester Copenhagen Study. ADAM12 levels were assayed in these serum samples. Serum levels of ADAM12 were converted to multiples of the median (MoM) after log-linear regression of concentration versus gestational age. RESULTS: Serum ADAM12 levels in women who developed preeclampsia during pregnancy had a mean log MoM of -0.066, which was significantly lower than the mean log MoM of -0.001 for ADAM12 levels observed in serum samples from women with normal pregnancy (P = .008). The mean log MoM was even lower in serum derived from preeclamptic women whose infant's weight at birth was less than 2,500 g (n = 27, mean log MoM of -0.120, P = .053). CONCLUSION: The maternal serum levels of ADAM12 are significantly lower during the first trimester in women who later develop preeclampsia during pregnancy when compared with levels in women with normal pregnancies. Because the secreted form of ADAM12 cleaves insulin-like growth factor binding protein (IGFBP)-3 and IGFBP-5, the IGF axis may play a role in preeclampsia. ADAM12 may be a useful early marker for preeclampsia. LEVEL OF EVIDENCE: II-2.

Combined first- and second-trimester screening for Down syndrome: an evaluation of proMBP as a marker.

OBJECTIVES: To estimate the screening performance of different combinations of first- and second-trimester markers, including a new marker, the proform of eosinophil major basic protein (proMBP). METHODS: The population comprised 195 singleton pregnancies with a normal outcome enrolled in the Copenhagen First Trimester Study, in which a serum sample was available from both the first and the second trimester. The performance of different marker combinations was estimated by receiver-operator-characteristics (ROC) analysis using a Monte Carlo simulation and distributions of log(10)MoM markers and their correlations, derived from our normal material and Down syndrome cases from the literature. RESULTS: Using a fixed screen-positive rate (SPR) of 5%, the first-trimester combined test [nuchal translucency (NT), PAPP-A and free beta-hCG] yielded a detection rate (DR) of 76%, and the integrated test (NT, PAPP-A, AFP, hCG, uE3 and inhibin A) yielded a DR of 86%. With a DR of 90%, the best combination was the first-trimester beta-hCG and NT with the second-trimester proMBP and AFP. ProMBP combined with the triple test increased the DR from 62 to 83%, whereas the addition of inhibin A only increased the DR to 69%. CONCLUSION: These results suggest that proMBP may be an important new marker in Down syndrome screening and, in particular, a good substitute for inhibin A.

Gender impact on first trimester markers in Down syndrome screening.

The influence of fetal gender on the level in the first trimester of the serological markers alpha-fetoprotein (AFP), pregnancy-associated plasma protein-A (PAPP-A) and free beta human chorionic gonadotropin (betahCG) and on nuchal translucency is described for 2637 singleton pregnancies with normal outcome. Mean log MoM values for pregnancies with female and male fetuses were calculated using regression of log marker values on gestational age expressed as crown rump length and on maternal weight. A pronounced gender impact was found for free betahCG, being 16% higher for female than for male fetuses.