Maternal tobacco use modestly alters correlated epigenome-wide placental DNA methylation and gene expression.

Several studies linking alterations in differential placental methylation with pregnancy disorders have implicated (de)regulation of the placental epigenome with fetal programming and later-in-life disease. We have previously demonstrated that maternal tobacco use is associated with alterations in promoter methylation of placental CYP1A1 and that these changes are correlated with CYP1A1 gene expression and fetal growth restriction. In this study we sought to expand our analysis of promoter methylation by correlating it to gene expression on a genome-wide scale. Employing side-by-side IlluminaHG-12 gene transcription with Infinium27K methylation arrays, we interrogated correlative changes in placental gene expression and DNA methylation associated with maternal tobacco smoke exposure at an epigenome-wide level and in consideration of signature gene pathways. We observed that the expression of 623 genes and the methylation of 1024 CpG dinucleotides are significantly altered among smokers, with only 38 CpGs showing significant differential methylation (differing by a methylation level of ≥10%). We identified a significant Pearson correlation (≥0.7 or ≤-0.7) between placental transcriptional regulation and differential CpG methylation in only 25 genes among non-smokers but in 438 genes among smokers (18-fold increase, p < 0.0001), with a dominant effect among oxidative stress pathways. Differential methylation at as few as 6 sites was attributed to maternal smoking-mediated birth weight reduction in linear regression models with Bonferroni correction (p < 1.8 × 10(-6)). These studies suggest that a common perinatal exposure (such as maternal smoking) deregulates placental methylation in a CpG site-specific manner that correlates with meaningful alterations in gene expression along signature pathways.

Rate of wound complications with enoxaparin use among women at high risk for postpartum thrombosis.

OBJECTIVE: To estimate the rate of wound complications associated with protocol-driven postcesarean enoxaparin thromboprophylaxis. METHODS: After implementing an Institutional Clinical Practice Guideline for postoperative cesarean delivery thromboprophylaxis among at-risk gravid women (older than 35 years of age, body mass index greater than 30 kg/m2, or both), data on all cesarean deliveries over the first 23 months of guideline implementation were extracted and analyzed. Primary (wound hematoma, separation, or dehiscence) and secondary (venous thromboembolism) outcomes were compared in stratified and multivariable models controlling for potential confounders. RESULTS: Over 23 months, 2,509 cesarean deliveries were performed. A total of 1,677 (68%) gravid women met criteria for thromboprophylaxis; 653 received enoxaparin per protocol ("cases"), and, at the discretion of the ordering physician, 1,024 did not (at-risk, protocol-noncompliant "controls"). Cases differed significantly by virtue of maternal age, body mass index, and diabetic status. Univariable analysis subsequently revealed a higher rate of wound separation (6.8% compared with 3.6%, P=.003), rehospitalization (2.1% compared with 0.8%, P=.017) and composite score (8.9% compared with 4.8%, P=.002) among protocol-compliant cases, but no increased risk of wound hematoma (P>.06). In multivariable analysis, adjusted odds ratios continued to reveal an association between enoxaparin use and wound separation (OR 1.66, P=.04) as well as higher composite score (OR 1.69, P=.01). However, among the protocol-noncompliant controls, a nonsignificant increase in the rate of venous thromboembolism occurred. CONCLUSION: In our series, prophylactic enoxaparin use among at-risk gravid women undergoing cesarean delivery was accompanied by an increased risk of wound separation. LEVEL OF EVIDENCE: II.

Influence of maternal BMI on genetic sonography in the FaSTER trial.

OBJECTIVE: We sought to evaluate the influence of maternal body mass index (BMI) on sonographic detection employing data from the FaSTER trial. METHOD: Unselected singleton pregnancies underwent detailed genetic sonogram to evaluate for structural fetal anomalies and soft markers for aneuploidy. BMI (kg/m(2)) were calculated from reported initial visit values. Sensitivity, specificity, false positive and false negative rates (FPR and FNR), likelihood ratio, detection rates, and a missed diagnosis rate (MDR: FNR + marker recorded as 'missing'/N) were calculated. RESULTS: Eight thousand five hundred and fifty-five patients with complete BMI information had detailed genetic sonography. A lower sensitivity with an elevated FNR and MDR was observed in obese women for multiple aneuploid markers (e.g. > or =2 markers 32% sensitivity with 68% FNR among BMI <25 vs 22% and 78% among BMI >30). Similarly, the detection rate for cardiac anomalies among women at BMI <25 was higher (21.6%) at a significantly lower FPR (78.4%; 95% CI 77.3-79.5%) in comparison to obese women (8.3% with FPR 91.7%; 95% CI 90.1-93.2%). In a logistic regression model, maternal obesity significantly decreased the likelihood of sonographic detection of common anomalies (adjusted OR 0.7; 95% CI 0.6-0.9; p = 0.001). CONCLUSION: The performance of second trimester genetic sonography is influenced by obesity, with a significantly higher MDR for multiple minor markers and lower likelihood for detecting common anomalies.

Pheochromocytoma and Von Hippel-Lindau in pregnancy.

Pheochromocytoma is an infrequent but well-acknowledged primary cause of malignant hypertension in pregnancy. Although the majority of pheochromocytomas are sporadic, those that present as bilateral or multifocal tumors may be a manifestation of a rare cancer susceptibility syndrome, such as Von Hippel-Lindau (VHL). Gravidae with unrecognized pheochromocytoma are at risk for recurrent paroxysmal hypertensive crises with ensuant maternal and fetal risks. To further illustrate the challenges of management of pheochromocytoma and VHL in pregnancy, we present two illustrative cases. In the first, a multigravida presented with an intrauterine fetal demise and malignant hypertension and a concurrent diagnosis of bilateral pheochromocytomas. A missense mutation in exon 3 of the VHL gene was identified, confirming the diagnosis of VHL type 2C. In the second case, a multigravida with a prior diagnosis of VHL syndrome but sporadic follow-up underwent renal and adrenal imaging surveillance as part of her prenatal care. Although she was normotensive and clinically asymptomatic, such imaging enabled the detection of bilateral pheochromocytomas. In summary, in this report we discuss our management in gravidae with pheochromocytoma and VHL, emphasizing current recommendations pertaining to obstetric management, genetic testing, and long-term follow-up.

Role of second-trimester genetic sonography after Down syndrome screening.

OBJECTIVE: To estimate the effectiveness of second-trimester genetic sonography in modifying Down syndrome screening test results. METHODS: The First and Second Trimester Evaluation of Risk (FASTER) aneuploidy screening trial participants were studied from 13 centers where a 15- to 23-week genetic sonogram was performed in the same center. Midtrimester Down syndrome risks were estimated for five screening test policies: first-trimester combined, second-trimester quadruple, and testing sequentially by integrated, stepwise, or contingent protocols. The maternal age-specific risk and the screening test risk were modified using likelihood ratios derived from the ultrasound findings. Separate likelihood ratios were obtained for the presence or absence of at least one major fetal structural malformation and for each "soft" sonographic marker statistically significant at the P<.005 level. Detection and false-positive rate were calculated for the genetic sonogram alone and for each test before and after risk modification. RESULTS: A total of 7,842 pregnancies were studied, including 59 with Down syndrome. Major malformations and 8 of the 18 soft markers evaluated were highly significant. The detection rate for a 5% false-positive rate for the genetic sonogram alone was 69%; the detection rate increased from 81% to 90% with the combined test, from 81% to 90% with the quadruple test, from 93% to 98% with the integrated test, from 97% to 98% with the stepwise test, and from 95% to 97% with the contingent test. The stepwise and contingent use of the genetic sonogram after first-trimester screening both yielded a 90% detection rate. CONCLUSION: Genetic sonography can increase detection rates substantially for combined and quadruple tests and more modestly for sequential protocols. Substituting sonography for quadruple markers in sequential screening was not useful. LEVEL OF EVIDENCE: II.

Loss of Erk3 function in mice leads to intrauterine growth restriction, pulmonary immaturity, and neonatal lethality.

Extracellular signal-regulated kinase 3 (Erk3) is an atypical member of the mitogen-activated protein (MAP) kinase family. No function has yet been ascribed to this MAP kinase. Here we show that targeted disruption of the Mapk6 gene (encoding Erk3) leads to intrauterine growth restriction, associated with marked pulmonary hypoplasia, and early neonatal death during the first day of life. Around 40% of Erk3(-/-) neonates die within minutes after birth from acute respiratory failure. Erk3-deficient mice have normal lung-branching morphogenesis, but show delayed lung maturation characterized by decreased sacculation, atelectasis, and defective type II pneumocyte differentiation. Interestingly, in utero administration of glucocorticoid promoted fetal lung maturity and rescued differentiation of type II cells, but failed to alter the neonatal lethality. We observed that loss of Erk3 retards intrauterine growth, as reflected by a marked reduction in fetal lung, heart, and liver weights, and by low body weight at birth. Importantly, we found that insulin-like growth factor (IGF)-2 levels are decreased in the serum of Erk3-deficient mice. Our findings reveal a critical role for Erk3 in the establishment of fetal growth potential and pulmonary function in the mouse.

A maternal high-fat diet is accompanied by alterations in the fetal primate metabolome.

OBJECTIVE: To characterize the serum metabolome of a primate model of in utero high-fat exposure. STUDY DESIGN: Serum from maternal and fetal (e130) macaque monkeys exposed to either a high-fat or control diet were analyzed by gas chromatography-mass spectrometry. Multivariate data analysis was performed to reduce the generated data set. Candidate metabolites were further analyzed for significance by using the analysis of variance and comparative t tests. RESULTS: Approximately 1300 chromatographic features were detected. Through multivariate data analysis this number was reduced to 60 possible metabolites. With the use of comparative t tests, 22 metabolites had statistical significance (P < .05) over the entire study. By virtue of maternal high-fat diet alone, fetal phenotypic differences are accompanied by altered metabolite concentrations of 7 metabolites (P < .05). CONCLUSION: In utero high-fat diet exposure is associated with an altered fetal epigenome and parlays a characteristic modification in the fetal metabolite profile.

Group A streptococcal puerperal sepsis: initial characterization of virulence factors in association with clinical parameters.

Group A beta-hemolytic streptococcus (GAS) is an uncommon but potentially fatal source of postpartum infection. Pathogenesis in invasive GAS infections has been linked to bacterial virulence factors. In this study, we sought to provide an initial description of potential virulence factors in association with puerperal morbidity by virtue of specific M-protein type antigens. Women with confirmed GAS puerperal infection in the Salt Lake City region were prospectively identified over a 6-year interval (1991-1997). From this cohort, GAS isolates were analyzed with respect to M-serotype and presence of genes encoding the Streptococcal Pyogenic Exotoxins A and B (SPE-A and SPE-B). Bacterial isolates from 18 subjects with GAS puerperal infection underwent M-serotyping and PCR-based genotyping for the speA and speB genes. Among these, 8/18 subjects manifest criteria of severe disease. All 18 isolate strains expressed speB; 6/18 isolates expressed speA. Of the M-serotypes, 8/8 severe disease isolates expressed M-types 1 (N=3) or 28 (N=5). Pulse-field gel electrophoresis did not indicate an outbreak strain among similar isolates. We conclude that in this initial characterization, morbidity among women with GAS puerperal infection is associated with M-types 1 and 28, but not speB genotype.

Animal models of epigenetic inheritance.

Although genomic DNA is the template of our heredity, it is the coordination and regulation of its expression that results in the wide complexity and diversity seen among organisms. In recent years, an emerging body of evidence has focused on the role of epigenetics as one mechanism by which gene expression can be maintained and modulated throughout the lifetime of an individual. Epigenetics refers to heritable alterations in gene expression that are not mediated by changes in primary DNA sequence and includes mitotic and/or meiotic events. In essence, epigenetic modulation results in functional adaptations of the genomic response to the environment and is believed to play a fundamental role in early developmental plasticity. This article focuses on several animal models that have been developed over the past decade to study epigenetic inheritance, many of which have arisen from the developmental origins of adult health and disease fields.

Environmental influences on epigenetic profiles.

Studies of environmental challenges, such as hazardous air pollutants, nonmutagenic toxins, diet choice, and maternal behavioral patterns, reveal changes in gene expression patterns, DNA methylation, and histone modifications that are in causal association with exogenous exposures. In this article we summarize some of the recent advances in the field of environmental epigenetics and highlight seminal studies that implicate in utero exposures as causative agents in altering not only the epigenome of the exposed gestation, but that of subsequent generations. Current studies of the effects of maternal behavior, exposure to environmental toxins, and exposure to maternal diet and an altered gestational milieu are summarized.

Developmental origins of disease and determinants of chromatin structure: maternal diet modifies the primate fetal epigenome.

Chromatin structure is epigenetically altered via covalent modifications of histones to allow for heritable gene regulation without altering the nucleotide sequence. Multiple lines of evidence from rodents have established a role for epigenetic remodeling in regulating gene transcription in response to an altered gestational milieu. However, to date, it is unknown whether variations in the intrauterine environment in primates similarly induce changes in key determinants of hepatic chromatin structure. We hypothesized that a maternal high-fat diet would alter the epigenomic profile of the developing offspring, which would result in alterations in fetal gene expression. Age- and weight-matched adult female Japanese macaques were placed on control (13% fat) or high-fat (35% fat) breeder diets and mated annually over a 4-year interval. Fetuses in successive years were delivered near term (e130 of 167 days) and underwent necropsy with tissue harvest. Fetal histones were acid extracted for characterization of H3 modification and chromatin immunoprecipitation (ChIP) with differential display PCR; fetal RNA, DNA, and cytoplasmic and nuclear protein extracts were similarly extracted for comparison. Chronic consumption of a maternal high-fat diet results in a threefold increase in fetal liver triglycerides and histologic correlates of non-alcoholic fatty liver disease. These gross changes in the fetal liver are accompanied by a statistically significant hyperacetylation of fetal hepatic tissue at H3K14 (199.85+/-9.64 vs 88.8+/-45.4; P=0.038) with a trend towards the increased acetylation at H3K9 (140.9+/-38.7 vs 46.6+/-6.53; P=0.097) and at H3K18 (69.0+/-3.54 vs 58.0+/-4.04; P=0.096). However, epigenetic modifications on fetal hepatic H3 associated with gene repression were absent or subtle (P>0.05). Subsequent characterization of key epigenetic determinants associated with H3 acetylation marks revealed similar significant alterations in association with a high-fat maternal diet (e.g., relative fetal histone deacetylase 1 (HDAC1) gene expression 0.61+/-0.25; P=0.011). Consistent with our mRNA expression profile, fetal nuclear extracts from offspring of high-fat diet animals were observed to be significantly relatively deplete of HDAC1 protein (36.07+/-6.73 vs 83.18+/-7.51; P=0.006) and in vitro HDAC functional activity (0.252+/-0.03 vs 0.698+/-0.02; P<0.001). We employ these observations in ChIP differential display PCR to attempt to identify potential fetal genes whose expression is reprogramed under conditions of a high-fat maternal diet. We quantitatively confirm a minimum of a 40% alteration in the expression of several genes of interest: glutamic pyruvate transaminase (alanine aminotransferase) 2 (GPT2) (1.59+/-0.23-fold; P=0.08), DNAJA2 (1.36+/-0.21; P=0.09), and Rdh12 (1.88+/-0.15; P=0.01) are appreciably increased in fetal hepatic tissue from maternal caloric-dense diet animals when compared with control while Npas2, a peripheral circadian regulator, was significantly downmodulated in the offspring of high-fat diet animals (0.66+/-0.08; P=0.03). In this study, we show that a current significant in utero exposure (caloric-dense high-fat maternal diet) induces site-specific alterations in fetal hepatic H3 acetylation. Employing ChIP, we extend these observations to link modifications of H3 acetylation with alterations in gene-specific expression. These results suggest that a caloric-dense maternal diet leading to obesity epigenetically alters fetal chromatin structure in primates via covalent modifications of histones and hence lends a molecular basis to the fetal origins of adult disease hypothesis.

Hyperemesis in pregnancy: an evaluation of treatment strategies with maternal and neonatal outcomes.

OBJECTIVE: The objective of the study was to evaluate the use of interventions such as a peripherally inserted central catheters (PICC) line or nasogastric (NG)/nasoduodenal (ND) tube with the use of medications alone in the management of pregnancies with hyperemesis. STUDY DESIGN: Subjects were identified with confirmed intrauterine pregnancy, admitted with hyperemesis gravidarum (HEG) between 1998 and 2004. Medical records were then abstracted for information with regard to therapy. Subjects were assigned on the basis of the management plan: medication alone, PICC line, or NG/ND tube. Outcomes were compared between groups. RESULTS: Ninety-four patients met study criteria and had complete outcome data available. Of those, 33 had a PICC line placed (35.1%), 19 had a NG/ND placed (20.2%), and 42 were managed with medication alone (44.7%). These groups were similar with respect to gestational age at delivery, Apgar score, and mean birthweight. Maternal complications were significantly higher among those with PICC lines. Of patients managed with PICC lines, 66.4% (P < .001) required treatment for infection, thromboembolism, or both. Adjusted odds ratio for a PICC line complication was 34.5 (5.09, 233.73). CONCLUSION: Maternal complications associated with PICC line placement are substantial despite no difference in neonatal outcomes, suggesting that the use of PICC lines for treatment of HEG patients should not be routinely used.

In utero tobacco exposure is associated with modified effects of maternal factors on fetal growth.

OBJECTIVE: The objective of the study was to evaluate whether maternal tobacco use is associated with an attenuation in fetal birthweight among women with nutritional and uteroplacental constraints. STUDY DESIGN: A population-based retrospective analysis of term (37 weeks or longer) singleton pregnancies delivered in Utah from 1991 to 2001. Birthweight (BW) and percent small for gestational age (SGA) (less than 10% for gestational age) among self-identified smokers and nonsmokers were compared. Adjusted odds ratios (ORs) were calculated to measure the association of maternal smoking with delivery of an SGA infant controlling for potential confounders across maternal strata. RESULTS: Among the 424,912 gestations, 37,076 occurred in self-identified smokers. Mean BW was significantly less and the prevalence of SGA infants was significantly greater in tobacco-exposed infants across all maternal BMI strata (P < .001) as well as pregnancies complicated by diabetes (P < .001) and hypertensive disorders (P < .001). In a multivariable logistic regression model, tobacco exposure remained the significant associative factor for SGA (OR 3.53, 95% confidence interval 2.61 to 4.79) after selecting for the first birth in the study interval (n = 283,916). CONCLUSION: Self-identified tobacco use increases the risk of a SGA infant at term across maternal strata.

Beckwith-Wiedemann syndrome presenting with an elevated triple screen in the second trimester of pregnancy.

BACKGROUND: Beckwith-Wiedemann syndrome (BWS) is a distinct clinical syndrome with unique features, generally diagnosed postnatally. CASE: A 26-year-old patient, gravida 4, para 3-0-0-3, was noted to have an abnormal maternal serum screen. Amniocentesis with imaging studies were remarkable only for a two-vessel umbilical cord and prominent maternal ovaries. The patient developed HELLP syndrome at 28 weeks and delivered a viable female infant with distinct clinical features. The diagnosis of BWS was confirmed by hypermethylation of the H19 gene on chromosome 11p15.5. CONCLUSION: This case describes a novel presentation of BWS and underscores the diagnostic potential of routine prenatal screens.

Preterm premature rupture of membranes in human immunodeficiency virus-infected women: a novel case series.

OBJECTIVE: To evaluate the management and outcomes of a series of human immunodeficiency virus-(HIV-) infected women whose pregnancies were complicated by preterm premature rupture of membranes (PPROM). STUDY DESIGN: We conducted a retrospective chart review of all women with confirmed HIV infection who had a pregnancy complicated by PPROM remote from term. PPROM remote from term was defined as rupture of membranes prior to 32-week gestation. Collective cases from two centers (Hennepin County Medical Center and The University of Alabama at Birmingham) were reviewed and data on management and outcomes were abstracted. RESULTS: Of the HIV-positive women, we identified 291 pregnancies having occurred in the study interval from two institutions. Of these pregnancies, 7 (2.4%) developed PPROM remote from term with subsequent delivery from 25- to 32-week gestation. Vertical HIV transmission was noted in 2 of 6 children whose long-term followup status was confirmed (33%) of these cases. However, both of these cases occurred in women with either no antepartum/intrapartum antiviral therapy or where only zidovudine monotherapy was used. Importantly, in spite of expectant management, no cases of vertical HIV transmission occurred in women who were receiving either multidrug or highly active antiviral therapy (HAART) at the time of PPROM and who had a cesarean delivery in cases where the predelivery viral load > 1000 copies/mL. CONCLUSION: Our limited observations raise the question as to whether in the current era of multidrug therapy immediate delivery should be undertaken in HIV+ pregnancies complicated by PPROM at an early gestational age. This case series further suggests that in those pregnancies that lend themselves to expectant management, such a strategy may be considered appropriate.

Preeclampsia and subsequent risk of cancer in Utah.

OBJECTIVE: The purpose of this study was to determine if preeclampsia is associated with a reduced risk of cancer later in life. STUDY DESIGN: We performed a cohort study where women with preeclampsia over the interval 1947 to 1999 were identified from the Utah Population Database. Preeclamptics (n = 17,432) were matched 1:3 with nonpreeclamptics (n = 52,296) on maternal age and birth year. Pregnancy, demographic, and cancer information was extracted from subjects and their offspring in linked datasets. Relative risk and hazard ratios were calculated. RESULTS: In a matched analysis using univariable random-effects Poisson regression, preeclampsia was protective against the development of cancer later in life (RR 0.91, 95% CI 0.84-0.99 with P = .027). In a multivariable clustered Cox regression model with the end point of cancer later in life, preeclampsia was associated with a lower risk of cancer (HR 0.92, 95% CI 0.85-0.99 with P = .039). These findings were supported by stratified and competing risk analyses. CONCLUSION: Women whose pregnancies were affected by preeclampsia have a decreased risk of developing cancer.

Immunology of normal pregnancy.

Since Medawar's initial contemplations in 1953 on the mechanisms of immune evasion allowing for the survival of the allogeneic conceptus in an immunologically competent mother, physicians and immunologists alike have struggled to understand the immunological paradox of pregnancy. Ultimately, our attempts to define the immunology of normal pregnancy have broadened our appreciation of the myriad mechanisms at play that enable the promotion of implantation and maintenance of pregnancy. In this review, we summarise what is known regarding the immunology of normal pregnancy, with special emphasis on the relation to common disorders of pregnancy.

Factors associated with nonanomalous stillbirths: the Utah Stillbirth Database 1992-2002.

OBJECTIVE: This study was undertaken to characterize risk factors associated with nonanomalous stillborn (SB) infants and to ascribe the probability of fetal survival by gestational age among high-risk pregnancies. STUDY DESIGN: We compiled a database of all SB infants and an equivalent number of controls using information obtained from Utah Birth and Fetal Death Certificates during the years 1992 through 2002. Adjusted and unadjusted odds ratios for risk factors associated with SB were generated. Cox proportional hazard models were used to generate survival curves comparing pregnancies complicated by chronic hypertension or gestational hypertension with those of controls. RESULTS: Infants with major anomalies were eliminated from both cases and controls, to generate 1566 nonanomalous SBs and 2720 nonanomalous controls. In a logistic regression model controlling for multiple maternal and fetal factors, placental abruption, hydramnios, cord prolapse, and essential hypertension were associated with an increased risk of SB. In pregnancies complicated by essential hypertension, the survival curve diverged from that of controls at those gestational ages approaching term (hazard ratio 2.24; 95% CI 1.52-3.32). CONCLUSION: SB in nonanomalous infants in Utah is more common among pregnancies complicated by placental abruption, hydramnios, cord prolapse, and essential hypertension.

Preterm premature rupture of membranes: perspectives surrounding controversies in management.

Preterm premature rupture of the membranes (PPROM) occurs in approximately 3% of all pregnancies, and accounts for one third of all preterm births. Despite its prevalence, optimal management of PPROM remains largely undefined and lacks conformity. In this article, we review the pathophysiology of PPROM, and summarize the available literature describing various management strategies in an effort to define current controversies in the management of PPROM.