Vascular health years after a hypertensive disorder of pregnancy: The EPOCH study.

BACKGROUND: Preeclampsia is associated with a two-fold increase in a woman's lifetime risk of developing atherosclerotic cardiovascular disease (ASCVD), but the reasons for this association are uncertain. The objective of this study was to examine the associations between vascular health and a hypertensive disorder of pregnancy among women ≥ 2 years postpartum. METHODS: Pre-menopausal women with a history of either a hypertensive disorder of pregnancy (cases: preeclampsia or gestational hypertension) or a normotensive pregnancy (controls) were enrolled. Participants were assessed for standard ASCVD risk factors and underwent vascular testing, including measurements of blood pressure, endothelial function, and carotid artery ultrasound. The primary outcomes were blood pressure, ASCVD risk, reactive hyperemia index measured by EndoPAT and carotid intima-medial thickness. The secondary outcomes were augmentation index normalized to 75 beats per minute and pulse wave amplitude measured by EndoPAT, and carotid elastic modulus and carotid beta-stiffness measured by carotid ultrasound. RESULTS: Participants had a mean age of 40.7 years and were 5.7 years since their last pregnancy. In bivariate analyses, cases (N = 68) were more likely than controls (N = 71) to have hypertension (18% vs 4%, P = .034), higher calculated ASCVD risk (0.6 vs 0.4, P = .02), higher blood pressures (systolic: 118.5 vs 111.6 mm Hg, P = .0004; diastolic: 75.2 vs 69.8 mm Hg, P = .0004), and higher augmentation index values (7.7 vs 2.3, P = .03). They did not, however, differ significantly in carotid intima-media thickness (0.5 vs 0.5, P = .29) or reactive hyperemia index (2.1 vs 2.1, P = .93), nor in pulse wave amplitude (416 vs 326, P = .11), carotid elastic modulus (445 vs 426, P = .36), or carotid beta stiffness (2.8 vs 2.8, P = .86). CONCLUSION: Women with a prior hypertensive disorder of pregnancy had higher ASCVD risk and blood pressures several years postpartum, but did not have more endothelial dysfunction or subclinical atherosclerosis.

Outcome of Pregnancy Oral Glucose Tolerance Test and Preterm Birth.

BACKGROUND: Gestational diabetes is associated with adverse outcomes such as preterm birth (<37 weeks). However, there is no international consensus on screening criteria or diagnostic levels for gestational diabetes, and it is unknown whether body mass index (BMI) or obesity modifies the relation between glucose level and preterm birth. METHODS: We studied a pregnancy cohort restricted to two Danish regions from the linked Danish Medical Birth Register to study associations between glucose measurements from the 2-hour postload 75-g oral glucose tolerance test (one-step approach) and preterm birth from 2004 to 2018. In Denmark, gestational diabetes screening is a targeted strategy for mothers with identified risk factors. We used Poisson regression to estimate rate ratios (RR) of preterm birth with z-standardized glucose measurements. We assessed effect measure modification by stratifying analyses and testing for heterogeneity. RESULTS: Among 11,337 pregnancies (6.2% delivered preterm), we observed an adjusted preterm birth RR of 1.2 (95% confidence interval [CI] = 1.1, 1.3) for a one-standard deviation glucose increase of 1.4 mmol/l from the mean of 6.7 mmol/l. There was evidence for effect measure modification by obesity, for example, adjusted RR for nonobese (BMI, <30): 1.2 (95% CI = 1.1, 1.3) versus obese (BMI, ≥30): 1.3 (95% CI = 1.2-1.5), P = 0.05 for heterogeneity. CONCLUSION: Among mothers screened for gestational diabetes, increased glucose levels, even those below the diagnostic level for gestational diabetes in Denmark, were associated with increased preterm birth risk. Obesity (BMI, ≥30) may be an effect measure modifier, not just a confounder, of the relation between blood glucose and preterm birth risk.

Large-scale proteomics in the first trimester of pregnancy predict psychopathology and temperament in preschool children: an exploratory study.

BACKGROUND: Understanding the prenatal origins of children's psychopathology is a fundamental goal in developmental and clinical science. Recent research suggests that inflammation during pregnancy can trigger a cascade of fetal programming changes that contribute to vulnerability for the emergence of psychopathology. Most studies, however, have focused on a handful of proinflammatory cytokines and have not explored a range of prenatal biological pathways that may be involved in increasing postnatal risk for emotional and behavioral difficulties. METHODS: Using extreme gradient boosted machine learning models, we explored large-scale proteomics, considering over 1,000 proteins from first trimester blood samples, to predict behavior in early childhood. Mothers reported on their 3- to 5-year-old children's (N = 89, 51% female) temperament (Child Behavior Questionnaire) and psychopathology (Child Behavior Checklist). RESULTS: We found that machine learning models of prenatal proteomics predict 5%-10% of the variance in children's sadness, perceptual sensitivity, attention problems, and emotional reactivity. Enrichment analyses identified immune function, nervous system development, and cell signaling pathways as being particularly important in predicting children's outcomes. CONCLUSIONS: Our findings, though exploratory, suggest processes in early pregnancy that are related to functioning in early childhood. Predictive features included far more proteins than have been considered in prior work. Specifically, proteins implicated in inflammation, in the development of the central nervous system, and in key cell-signaling pathways were enriched in relation to child temperament and psychopathology measures.

Bias analyses to investigate the impact of differential participation: Application to a birth defects case-control study.

BACKGROUND: Certain associations observed in the National Birth Defects Prevention Study (NBDPS) contrasted with other research or were from areas with mixed findings, including no decrease in odds of spina bifida with periconceptional folic acid supplementation, moderately increased cleft palate odds with ondansetron use and reduced hypospadias odds with maternal smoking. OBJECTIVES: To investigate the plausibility and extent of differential participation to produce effect estimates observed in NBDPS. METHODS: We searched the literature for factors related to these exposures and participation and conducted deterministic quantitative bias analyses. We estimated case-control participation and expected exposure prevalence based on internal and external reports, respectively. For the folic acid-spina bifida and ondansetron-cleft palate analyses, we hypothesized the true odds ratio (OR) based on prior studies and quantified the degree of exposure over- (or under-) representation to produce the crude OR (cOR) in NBDPS. For the smoking-hypospadias analysis, we estimated the extent of selection bias needed to nullify the association as well as the maximum potential harmful OR. RESULTS: Under our assumptions (participation, exposure prevalence, true OR), there was overrepresentation of folic acid use and underrepresentation of ondansetron use and smoking among participants. Folic acid-exposed spina bifida cases would need to have been ≥1.2× more likely to participate than exposed controls to yield the observed null cOR. Ondansetron-exposed cleft palate cases would need to have been 1.6× more likely to participate than exposed controls if the true OR is null. Smoking-exposed hypospadias cases would need to have been ≥1.2 times less likely to participate than exposed controls for the association to falsely appear protective (upper bound of selection bias adjusted smoking-hypospadias OR = 2.02). CONCLUSIONS: Differential participation could partly explain certain associations observed in NBDPS, but questions remain about why. Potential impacts of other systematic errors (e.g. exposure misclassification) could be informed by additional research.

Increased Risk of Preterm Delivery Subtypes and Hypertensive Disorders of Pregnancy in First Deliveries of Patients With Systemic Vasculitis.

OBJECTIVE: The goal of this study was to investigate the risk of preterm birth subtypes and hypertensive disorders of pregnancy in patients with systemic vasculitis using large, statewide databases. METHODS: Births to nulliparous patients with prevalent systemic vasculitides (Takayasu arteritis [TAK], Behçet disease [BD], antineutrophil cytoplasmic antibody-associated vasculitis [AAV], and Kawasaki disease [KD]) were identified using International Classification of Diseases, Ninth Revision codes in linked administrative data and birth records from the California Department of Health Care Access and Information and California Vital Statistics from 1991 to 2012. Hypertensive disorders of pregnancy and preterm delivery (PTD) subtypes were identified. Multivariable-adjusted Poisson models estimated risk ratios (RRs) of these outcomes compared with the general birthing population without history of rheumatic disease. RESULTS: A total of 96 births to nulliparous patients with systemic vasculitis were identified (TAK, 14; AAV, 31; BD, 26; KD, 15) and compared with 4,191,900 births of the nulliparous general population. Adjusted RRs for all PTD types were elevated in patients with vasculitis (RR 3.21, 95% confidence interval [CI] 2.15-4.79), as were the RRs of all PTD subtypes including preterm premature rupture of membranes (RR 4.30, 95% CI 2.05-9.01) and spontaneous PTD (RR 4.99, 95% CI 3.01-8.28). Of the spontaneous PTDs among patients with vasculitis, 16.7% were early PTDs (20-31 weeks), with the remaining 83.3% occurring between 32 to 36 weeks. Patients with vasculitis also had an elevated risk of hypertensive disorders of pregnancy (RR 2.96, 95% CI 1.72-5.10). CONCLUSION: Among first-time births, we found that patients with systemic vasculitis have an elevated risk of PTD subtypes as well as hypertensive disorders of pregnancy.

A search for factors associated with reduced carbohydrate intake and NTD risk in two population-based studies.

BACKGROUND: Two population-based case-control studies have reported an increased risk of neural tube defect (NTD)-affected pregnancies among women with low carbohydrate diet in the periconceptional period. Given that only two studies have investigated this association, it is unclear to what degree the findings could be impacted by residual confounding. Here, we further interrogated both studies that observed this association with the objective to identify factors from a much larger number of factors that might explain the association. METHODS: By employing a machine learning algorithm (random forest), we investigated a baseline set of over 200 variables. These analyses produced the top 10 variables in each data set for cases and controls that predicted periconceptional low carbohydrate intake. RESULTS: Examining those prediction variables with logistic regression modeling, we did not observe any particular variable that substantially contributed to the NTD-low carbohydrate association in either data set. CONCLUSIONS: If there are underlying factors that explain the association, our findings suggest that none of the 200+ variables we examined were sufficiently correlated with what that true explanatory exposure may be. Alternatively, our findings may suggest that there are other unidentified factor(s) at play, or the association observed in two independent data sets is directly related to low carbohydrate intake.

Preconception dietary glycemic index and risk for large-for-gestational age births.

OBJECTIVES: Diets with a high glycemic index (GI) leading to elevated postprandial glucose levels and hyperinsulinemia during pregnancy have been inconsistently linked to an increased risk for large-for-gestational-age (LGA) births. The effects of prepregnancy dietary GI on LGA risk are, to our knowledge, unknown. We examined the association of prepregnancy dietary GI with LGA births and joint associations of GI and maternal overweight/obesity and infant sex with LGA births among 10 188 infants born without congenital anomalies from 1997 to 2011, using data from the National Birth Defects Prevention Study (NBDPS). The aim of this study was to investigate this association among infants without major congenital anomalies (controls) who participated in the NBDPS and to evaluate how prepregnancy BMI and infant sex may modify this association on the additive scale. METHODS: Dietary intake was ascertained using a 58-item food frequency questionnaire. We dichotomized dietary GI into high and low categories using spline regression models. Infants with a birth weight at or above the 90th percentile for gestational age and sex, according to a U.S. population reference, were considered LGA. We used logistic regression to obtain odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Of the infants, 859 (9%) had a high dietary GI (cut-point: 59), and 1244 infants (12%) were born LGA. Unadjusted analysis suggested an inverse association between high dietary GI and LGA (OR, 0.79; 95% CI, 0.62-0.99). No association was observed in multivariable models when comparing high dietary GI intake between LGA births and all other births (OR, 0.94; 95% CI, 0.74-1.20) or when excluding small-for-gestational-age (SGA) births (OR, 0.94; 95% CI, 0.73-1.19). No joint associations with maternal overweight/obesity or infant sex were observed. CONCLUSION: High prepregnancy maternal GI was not associated with LGA births independently of or jointly with other factors.

Ambient Environment and the Epidemiology of Preterm Birth.

Preterm birth (PTB) is associated with substantial mortality and morbidity. We describe environmental factors that may influence PTB risks. We focus on exposures associated with an individual's ambient environment, such as air pollutants, water contaminants, extreme heat, and proximities to point sources (oil/gas development or waste sites) and greenspace. These exposures may further vary by other PTB risk factors such as social constructs and stress. Future examinations of risks associated with ambient environment exposures would benefit from consideration toward multiple exposures - the exposome - and factors that modify risk including variations associated with the structural genome, epigenome, social stressors, and diet.

Solving the Puzzle of Preterm Birth.

Solving the puzzle of preterm birth has been challenging and will require novel integrative solutions as preterm birth likely arises from many etiologies. It has been demonstrated that many sociodemographic and psychological determinants of preterm birth relate to its complex biology. It is this understanding that has enabled the development of a novel preventative strategy, which integrates the omics profile (genome, epigenome, transcriptome, proteome, metabolome, microbiome) with sociodemographic, environmental, and psychological determinants of individual pregnant people to solve the puzzle of preterm birth.

Hydroxychloroquine in Lupus Pregnancy and Risk of Preeclampsia.

OBJECTIVE: Systemic lupus erythematosus (SLE) disproportionately affects women during childbearing years, and hydroxychloroquine (HCQ) is the standard first-line treatment. Preeclampsia complicates up to one-third of pregnancies in lupus patients, although reports vary by parity and multifetal gestation. We investigated whether taking HCQ early in pregnancy may reduce the risk of preeclampsia. METHODS: We studied 1,068 live birth singleton pregnancies among 1,020 privately insured patients with SLE (2007-2016). HCQ treatment was defined as three months preconception through the first trimester, and prescription fills were a proxy for taking HCQ. Modified Poisson regression estimated risk ratios (RRs) and 95% confidence intervals (CIs), stratified by parity. Propensity scores accounted for confounders, and stratified analyses examined effect modification. RESULTS: Approximately 15% of pregnant patients were diagnosed with preeclampsia. In 52% of pregnancies, patients had one or more HCQ fills. Pregnant patients exposed to HCQ had more comorbidities, SLE activity, and azathioprine treatment. We found no evidence of a statistical association between HCQ and preeclampsia among nulliparous (RR 1.26 [95% CI 0.82-1.93]) and multiparous pregnancies (RR 1.20 [95% CI 0.80-1.70]). Additional controls for confounding decreased the RRs toward the null (nulliparous pregnancy, propensity score-adjusted [PS-adj] RR 1.09 [95% CI 0.68-1.76]; multiparous pregnancy, PS-adj RR 1.01 [95% CI 0.66-1.53]). CONCLUSION: Using a large insurance-based database, we did not observe a decreased risk of preeclampsia associated with HCQ treatment in pregnancy, although we cannot rule out residual and unmeasured confounding and misclassification. Further studies leveraging large population-based data and prospective collection could characterize how HCQ influences preeclampsia risk in pregnant patients with SLE and among persons at greater risk of hypertensive disorders of pregnancy.

Hydroxychloroquine and Pre-eclampsia in a Diverse Cohort of Women With Systemic Lupus Erythematosus.

OBJECTIVE: Patients with systemic lupus erythematosus (SLE) are at risk for pregnancy complications such as pre-eclampsia and eclampsia. These clinically important complications are associated with maternal morbidity, mortality, and postpartum cardiovascular disease. Some studies suggest that hydroxychloroquine (HCQ) may reduce pre-eclampsia risk in lupus pregnancy. Using a cohort of pregnant patients with prevalent SLE at Kaiser Permanente Northern California (KPNC), we investigated whether HCQ treatment in early pregnancy reduced the risk of pre-eclampsia or eclampsia. METHODS: Among pregnant patients with SLE from 2011 to 2020, we assessed HCQ treatment from three months before pregnancy through the first trimester. HCQ exposure was defined multiple ways to account for adherence and duration of treatment. Propensity scores accounted for multiple confounders and modified Poisson models estimated risk ratios (RRs) and 95% confidence intervals of the association between HCQ treatment and pre-eclampsia or eclampsia. Effect modification by pregestational hypertension, history of nephritis, and antiphospholipid antibody (aPL) status was investigated through stratified analysis. RESULTS: There were 399 pregnancies among 324 patients with SLE at KPNC between 2011 and 2020. Considering multiple exposure definitions, we consistently found a null association between HCQ and pre-eclampsia or eclampsia. The RRs were consistently lower among nullipara patients, and RRs were consistently protective but not statistically significant among the high-risk subgroup of patients with a history of nephritis, aPL positivity, or pregestational hypertension (for both nullipara and multipara patients). CONCLUSION: Although this study found no reduced risk of HCQ on pre-eclampsia or eclampsia, residual confounding may be attenuating the effect despite an integrated health care delivery system setting with detailed clinical data.

Pregnancy Outcomes in a Diverse US Lupus Cohort.

OBJECTIVE: Although the population of patients with systemic lupus erythematosus (SLE) is racially and ethnically diverse, many study populations are homogeneous. Further, data are often lacking on critical factors, such as antiphospholipid antibodies (aPLs). We investigated live birth rates in patients with SLE at Kaiser Permanente Northern California, including race and ethnicity and aPL data. METHODS: Electronic health records of pregnancies with outcomes observed from 2011 to 2020 were identified among patients with SLE. Prevalent SLE was defined as two or more International Classification of Diseases-coded visits seven or more days apart before the last menstrual period. We summarized patient characteristics, medication orders, health care use, and medication use. Pregnancy outcomes (live birth, stillbirth, spontaneous abortion, ectopic pregnancy, and molar pregnancy) were presented overall and stratified by race and ethnicity, aPL status, and nephritis history. RESULTS: We identified 657 pregnancies among 453 patients with SLE. The cohort was diverse, reflecting the Northern California population (27% Asian, 26% Hispanic, 26% Non-Hispanic White, 13% Non-Hispanic Black, 5% multiracial, and approximately 2% Pacific Islander and Native American). Approximately 74% of observed pregnancies ended in live birth, 23% resulted in spontaneous abortion, 2% were ectopic or molar pregnancies, and <1% were stillbirths. There was limited variability in live births by race and ethnic group (72%-79%), aPL status (69.5%-77%), and nephritis history (71%-75%). CONCLUSION: Our findings are consistent with previous studies; however, some methodologic differences may yield a range of live birth rates. We found that approximately 74% of pregnancies in patients with SLE ended in live birth, with modest variability in spontaneous abortion by race and ethnicity, nephritis history, and aPL status.

Corrigendum: Advances and potential of omics studies for understanding the development of food allergy.

[This corrects the article DOI: 10.3389/falgy.2023.1149008.].

Factors associated with infant sex and preterm birth status for selected birth defects from the National Birth Defects Prevention Study, 1997-2011.

BACKGROUND: Birth defects and preterm birth co-occur, with some overlapping risk factors. Many birth defects and preterm births tend to have a male preponderance. We explored potential risk factors impacting sex and preterm (<37 weeks of gestation) birth differences among infants with selected birth defects delivered from 1997 to 2011 using data from the National Birth Defects Prevention Study (NBDPS). METHODS: The NBDPS was a large multisite, population-based case-control study. Using random forests, we identified important predictors of male preterm, female preterm, and male term, each compared with female term births for each birth defect. Using logistic regression, we estimated odds ratios for associations between important predictors and sex-preterm birth status by birth defect. RESULTS: We examined 11,379 infants with nine specific birth defects. The top 10 most important predictors of sex-preterm birth status from the random forests varied greatly across the birth defects and sex-preterm comparisons within a given defect group, with several being novel factors. However, one consistency was that short interpregnancy interval was associated with sex-preterm birth status for many of the studied birth defects. Although obesity has been identified as a risk factor for preterm birth and birth defects in other research, it was not associated with sex-preterm birth status for any of the examined defects. CONCLUSIONS: We confirmed expected associations for sex-preterm birth status differences and found new potential risk factors for further exploration among the studied birth defects.

Mode of delivery predicts postpartum maternal leukocyte telomere length.

BACKGROUND: Recent studies have suggested that pregnancy accelerates biologic aging, yet little is known about how biomarkers of aging are affected by events during the peripartum period. Given that immune shifts are known to occur following surgery, we explored the relation between mode of delivery and postpartum maternal leukocyte telomere length (LTL), a marker of biologic aging. STUDY DESIGN: Postpartum maternal blood samples were obtained from a prospective cohort of term, singleton livebirths without hypertensive disorders or peripartum infections between 2012 and 2018. The primary outcome was postpartum LTLs from one blood sample drawn between postpartum week 1 and up to 6 months postpartum, measured from thawed frozen peripheral blood mononuclear cells using quantitative PCR in basepairs (bp). Multivariable linear regression models compared LTLs between vaginal versus cesarean births, adjusting for age, body mass index, and nulliparity as potential confounders. Analyses were conducted in two mutually exclusive groups: those with LTL measured postpartum week 1 and those measured up to 6 months postpartum. Secondarily, we compared multiomics by mode of delivery using machine-learning methods to evaluate whether other biologic changes occurred following cesarean. These included transcriptomics, metabolomics, microbiomics, immunomics, and proteomics (serum and plasma). RESULTS: Of 67 included people, 50 (74.6 %) had vaginal and 17 (25.4 %) had cesarean births. LTLs were significantly shorter after cesarean in postpartum week 1 (5755.2 bp cesarean versus 6267.8 bp vaginal, p = 0.01) as well as in the later draws (5586.6 versus 5945.6 bp, p = 0.04). After adjusting for confounders, these differences persisted in both week 1 (adjusted beta -496.1, 95 % confidence interval [CI] -891.1, -101.1, p = 0.01) and beyond (adjusted beta -396.8; 95 % CI -727.2, -66.4. p = 0.02). Among the 15 participants who also had complete postpartum multiomics data available, there were predictive signatures of vaginal versus cesarean births in transcriptomics (cell-free [cf]RNA), metabolomics, microbiomics, and proteomics that did not persist after false discovery correction. CONCLUSION: Maternal LTLs in postpartum week 1 were nearly 500 bp shorter following cesarean. This difference persisted several weeks postpartum, even though other markers of inflammation had normalized. Mode of delivery should be considered in any analyses of postpartum LTLs and further investigation into this phenomenon is warranted.

Sociodemographic Trends and Perinatal Outcomes in Fathers 50 Years and Older.

Importance: The age of fathers at childbirth is rising, with an increasing number of births attributed to older fathers. While the impact of advanced paternal age has been documented, sociodemographic data about fathers aged 50 years and older remain scarce. Objectives: To explore sociodemographic and temporal trends among the oldest US fathers (age ≥50 years) and their associations with perinatal outcomes. Design, Setting, and Participants: This retrospective cross-sectional study included data from all US births from 2011 to 2022 using the National Vital Statistics System. Data were analyzed from August 2023 and May 2024. Exposures: Reported paternal age at childbirth. Main Outcomes and Measures: Outcomes of interest were sociodemographic factors, temporal trends in older fatherhood, and perinatal outcomes, including preterm birth, low birth weight, gestational diabetes, gestational hypertension, assisted reproductive technology (ART), rates of maternal primiparity, and the infant sex ratio. Results: From 2011 to 2022, the US recorded 46 195 453 births, with an overall mean (SD) paternal age of 31.5 (6.8) years and 484 507 (1.1%) involving fathers aged 50 years or older, 47 785 (0.1%) aged 60 years or older, and 3777 (0.008%) aged 70 years or older. Births to fathers aged 50 years or older increased from 1.1% in 2011 to 1.3% in 2022 (P for trend < .001). Fathers aged 50 years or older were more diverse, with variations in educational achievement and race and ethnicity. Marital status and maternal racial and ethnic and educational backgrounds also varied by paternal age and race. Despite controlling for maternal age and other sociodemographic and perinatal factors, every 10-year increase in paternal age was consistently associated with greater use of ART (eg, age 50-59 years: adjusted odds ratio [aOR], 2.23; 95% CI, 2.19-2.27), higher likelihood of first maternal birth (eg, age 50-59 years: aOR, 1.16; 95% CI, 1.15-1.17), and increased risks of preterm birth (eg, age 50-59 years: aOR, 1.16; 95% CI, 1.15-1.18) and low birth weight (eg, age 50-59 years: aOR, 1.14; 95% CI, 1.13-1.15) compared with fathers aged 30 to 39 years. No significant changes in the infant sex ratio were observed, except among fathers aged 70 years or older (aOR, 0.92; 95% CI, 0.86-0.99) and 75 years or older (aOR, 0.84; 95% CI, 0.73-0.97), who showed a decreased likelihood of having male offspring. Conclusions and Relevance: In this cross-sectional study of all US births from 2011 to 2022, the percentage attributed to older fathers, while small, increased. Notable variations in paternal and maternal race and education were identified. Older fatherhood was associated with increased ART use, first-time maternal births, adverse perinatal outcomes, and altered sex ratio. Further research of this population is crucial for improving patient counseling and family planning.

Genome-wide study of gene-by-sex interactions identifies risks for cleft palate.

Structural birth defects affect 3-4% of all live births and, depending on the type, tend to manifest in a sex-biased manner. Orofacial clefts (OFCs) are the most common craniofacial structural birth defects and are often divided into cleft lip with or without cleft palate (CL/P) and cleft palate only (CP). Previous studies have found sex-specific risks for CL/P, but these risks have yet to be evaluated in CP. CL/P is more common in males and CP is more frequently observed in females, so we hypothesized there would also be sex-specific differences for CP. Using a trio-based cohort, we performed sex-stratified genome-wide association studies (GWAS) based on proband sex followed by a genome-wide gene-by-sex (GxS) interaction testing. There were 13 loci significant for GxS interactions, with the top finding in LTBP1 (RR=3.37 [2.04 - 5.56], p=1.93x10 -6 ). LTBP1 plays a role in regulating TGF-B bioavailability, and knockdown in both mice and zebrafish lead to craniofacial anomalies. Further, there is evidence for differential expression of LTBP1 between males and females in both mice and humans. Therefore, we tested the association between the imputed genetically regulated gene expression of genes with significant GxS interactions and the CP phenotype. We found significant association for LTBP1 in cell cultured fibroblasts in female probands (p=0.0013) but not in males. Taken altogether, we show there are sex-specific risks for CP that are otherwise undetectable in a combined sex cohort, and LTBP1 is a candidate risk gene, particularly in females.

Integrative analysis of noncoding mutations identifies the druggable genome in preterm birth.

Preterm birth affects ~10% of pregnancies in the US. Despite familial associations, identifying at-risk genetic loci has been challenging. We built deep learning and graphical models to score mutational effects at base resolution via integrating the pregnant myometrial epigenome and large-scale patient genomes with spontaneous preterm birth (sPTB) from European and African American cohorts. We uncovered previously unidentified sPTB genes that are involved in myometrial muscle relaxation and inflammatory responses and that are regulated by the progesterone receptor near labor onset. We studied genomic variants in these genes in our recruited pregnant women administered progestin prophylaxis. We observed that mutation burden in these genes was predictive of responses to progestin treatment for preterm birth. To advance therapeutic development, we screened ~4000 compounds, identified candidate molecules that affect our identified genes, and experimentally validated their therapeutic effects on regulating labor. Together, our integrative approach revealed the druggable genome in preterm birth and provided a generalizable framework for studying complex diseases.

Exome sequencing identifies novel genes underlying primary congenital glaucoma in the National Birth Defects Prevention Study.

BACKGROUND: Primary congenital glaucoma (PCG) affects approximately 1 in 10,000 live born infants in the United States (U.S.). PCG has a autosomal recessive inheritance pattern, and variable expressivity and reduced penetrance have been reported. Likely causal variants in the most commonly mutated gene, CYP1B1, are less prevalent in the U.S., suggesting that alternative genes may contribute to the condition. This study utilized exome sequencing to investigate the genetic architecture of PCG in the U.S. and to identify novel genes and variants. METHODS: We studied 37 family trios where infants had PCG and were part of the National Birth Defects Prevention Study (births 1997-2011), a U.S. multicenter study of birth defects. Samples underwent exome sequencing and sequence reads were aligned to the human reference sample (NCBI build 37/hg19). Variant filtration was conducted under de novo and Mendelian inheritance models using GEMINI. RESULTS: Among candidate variants, CYP1B1 was most represented (five trios, 13.5%). Twelve probands (32%) had potentially pathogenic variants in other genes not previously linked to PCG but important in eye development and/or to underlie Mendelian conditions with potential phenotypic overlap (e.g., CRYBB2, RXRA, GLI2). CONCLUSION: Variation in the genes identified in this population-based study may help to further explain the genetics of PCG.

Gestational Dating by Urine Metabolic Profile at High Resolution Weekly Sampling Timepoints: Discovery and Validation.

Background: Pregnancy triggers longitudinal metabolic alterations in women to allow precisely-programmed fetal growth. Comprehensive characterization of such a "metabolic clock" of pregnancy may provide a molecular reference in relation to studies of adverse pregnancy outcomes. However, a high-resolution temporal profile of metabolites along a healthy pregnancy remains to be defined. Methods: Two independent, normal pregnancy cohorts with high-density weekly urine sampling (discovery: 478 samples from 19 subjects at California; validation: 171 samples from 10 subjects at Alabama) were studied. Urine samples were profiled by liquid chromatography-mass spectrometry (LC-MS) for untargeted metabolomics, which was applied for gestational age dating and prediction of time to delivery. Results: 5,473 urinary metabolic features were identified. Partial least-squares discriminant analysis on features with robust signals (n = 1,716) revealed that the samples were distributed on the basis of the first two principal components according to their gestational age. Pathways of bile secretion, steroid hormone biosynthesis, pantohenate, and CoA biosynthesis, benzoate degradation, and phenylpropanoid biosynthesis were significantly regulated, which was collectively applied to discover and validate a predictive model that accurately captures the chronology of pregnancy. With six urine metabolites (acetylcholine, estriol-3-glucuronide, dehydroepiandrosterone sulfate, α-lactose, hydroxyexanoy-carnitine, and l-carnitine), models were constructed based on gradient-boosting decision trees to date gestational age in high accordance with ultrasound results, and to accurately predict time to delivery. Conclusion: Our study characterizes the weekly baseline profile of the human pregnancy metabolome, which provides a high-resolution molecular reference for future studies of adverse pregnancy outcomes.