Hyagriv N Simhan

University of Pittsburgh, Pittsburgh, Pennsylvania, United States

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Publications (210)963.88 Total impact


  • No preview · Article · Jan 2015 · American Journal of Obstetrics and Gynecology

  • No preview · Article · Jan 2015 · American Journal of Obstetrics and Gynecology

  • No preview · Article · Jan 2015 · American Journal of Obstetrics and Gynecology
  • Lisa M Bodnar · Robert W Platt · Hyagriv N Simhan
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    ABSTRACT: To estimate the association between maternal 25-hydroxyvitamin D concentrations and risk of preterm birth subtypes. We performed a case-cohort study using data and banked samples from patients at a teaching hospital in Pittsburgh, Pennsylvania. Eligible participants were women with a prenatal aneuploidy screening serum sample at or before 20 weeks of gestation who subsequently delivered a singleton, liveborn neonate. Of the 12,861 eligible women, we selected 2,327 at random as well as all remaining preterm birth cases for a total of 1,126 cases. Serum 25-hydroxyvitamin D was measured using liquid chromatography-tandem mass spectrometry. Multivariable log-binomial regression models were used to estimate associations between maternal vitamin D status and preterm birth at 37 weeks of gestation (separately by spontaneous or indicated) and preterm birth at less than 34 weeks of gestation. The incidence of preterm birth at less than 37 weeks of gestation was 8.6% overall and 11.3%, 8.6%, and 7.3% among mothers with serum 25-hydroxyvitamin D less than 50, 50-74.9, and 75 nmol/L or greater, respectively (P<.01). After adjustment for maternal race and ethnicity, prepregnancy body mass index, season, smoking, and other confounders, the risk of preterm birth at less than 37 weeks of gestation significantly decreased as 25-hydroxyvitamin D increased to approximately 90 nmol/L and then plateaued (test of nonlinearity P<.01). Results were similar when limiting to cases that were medically indicated or occurred spontaneously and cases occurring at less than 34 weeks of gestation. Our data support a protective association maternal vitamin D sufficiency and preterm birth that combined with extant epidemiologic data may provide justification for a randomized clinical trial of maternal vitamin D replacement or supplementation to prevent preterm birth. LEVEL OF EVIDENCE:: II.
    No preview · Article · Jan 2015 · Obstetrics and Gynecology
  • Jennifer A Hutcheon · Lisa M Bodnar · Hyagriv N Simhan
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    ABSTRACT: To explore whether state restrictions on Medicaid funding for pregnancy termination of anomalous fetuses could be contributing to the black-white disparity in infant death resulting from congenital anomalies. Data on deaths resulting from anomalies were obtained from U.S. vital statistics records (1983-2004) and the Nationwide Inpatient Sample (2003-2007). We conducted an ecological study using Poisson and logistic regression to explore the association between state Medicaid funding for pregnancy terminations of anomalous fetuses and infant death resulting from anomalies by calendar time, race, and individual Medicaid status. Since 1983, a gap in anomaly-related infant death has developed between states without compared with those with Medicaid funding for pregnancy termination (rate ratio in 2004 1.21, 95% confidence interval [CI] 1.18-1.24; crude risks: 146.8 compared with 121.7/100,000). Blacks were significantly more likely than whites to be on Medicaid (60.2% compared with 29.2%) and to live in a state without Medicaid funding for pregnancy termination (65.8% compared with 59.6%). The increased risk of anomaly-related death associated with lack of state Medicaid funding for pregnancy termination was most pronounced among black women on Medicaid (relative risk 1.94, 95% CI 1.52-2.36; crude risks: 245.5 compared with 129.3/100,000). States without Medicaid funding for pregnancy termination of anomalous fetuses have higher rates of infant death resulting from anomalies than those with funding, and this difference is most pronounced among black women on Medicaid. Restrictions on Medicaid funding for termination of anomalous fetuses potentially could be contributing to the black-white disparity in anomaly-related infant death. : II.
    No preview · Article · Jan 2015 · Obstetrics and Gynecology
  • Raj Shree · Hyagriv N Simhan
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    ABSTRACT: Objective Both history of spontaneous preterm birth (sPTB) and shorter interpregnancy intervals (IPIs) increase the risk of recurrent sPTB. Mechanisms underlying the association between IPI and recurrent sPTB are unknown. We have previously demonstrated that higher concentrations of cervical anti-inflammatory cytokines are a risk factor for sPTB and upper genital tract inflammation. Here, we examine the association between IPI and cervical anti-inflammatory cytokines among women with previous sPTB. Patients and Methods A prospective cohort of 73 women with previous sPTB and cervical interleukins (IL-4, IL-10, and IL-13) measured at < 16 weeks. Using the published principal factor analysis, the anti-inflammatory (ANTI) score was calculated. From our previous work, higher ANTI scores increase the subsequent risk of sPTB. IPI was the time from the previous birth to the conception of current pregnancy. Confounders included education level, marital status, gonorrhea, chlamydia, body mass index, race, and cigarette smoking. IPI and ANTI score were analyzed using univariable and multivariable analyses. Results There was a significant negative linear relation between IPI and ANTI score (β = -0.075, p = 0.017). This persisted after adjustment for confounders (p = 0.02). As IPI decreases by 1 month, the ANTI-score-associated risk of sPTB increases approximately by 4%. Conclusion Among women with previous sPTB, there was a significant negative linear relation between IPI and ANTI score. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.
    No preview · Article · Dec 2014 · American Journal of Perinatology
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    ABSTRACT: To test the feasibility of conducting a pragmatic randomized controlled trial (RCT) comparing the International Association of Diabetes in Pregnancy Study Groups (IADPSG) versus Carpenter-Coustan diagnostic criteria for gestational diabetes (GDM), and to examine patient and provider views on GDM screening. A single-blinded pragmatic pilot RCT. Participants with a singleton pregnancy between 24 and 28 weeks gestation received a 50 g oral glucose challenge test and if the value was <200 mg/dL were randomized to either the 2 h 75 g OGTT using the IADPSG criteria or the 3 h 100 g OGTT using the Carpenter-Coustan criteria. Primary outcome was the feasibility of randomization and screening. Secondary outcomes included patient and provider views (or preferences) on GDM testing. Sixty-eight women were recruited, 48 (71 %) enrolled and 47 (69 %) were randomized. Participants in both study arms identified the main challenges to GDM testing to be: drinking the glucola, fasting prior to testing, waiting to have blood drawn, and multiple venipuntures. Women in both study arms would prefer the 2 h 75 g OGTT or whichever test is recommended by their doctor in a future pregnancy. Physicians and nurse midwives endorsed screening and were comfortable with being blinded to the GDM testing strategy and results values. Both pregnant women and providers value GDM screening, and pregnant women can be recruited to a blinded, randomized GDM screening trial with minimal attrition and missing data.
    No preview · Article · Nov 2014 · Maternal and Child Health Journal
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    ABSTRACT: Placenta accreta spectrum is one of the most morbid conditions obstetricians will encounter. The incidence has dramatically increased in the last twenty years. The major contributing factor to this is believed to be the increase in the rate of cesarean delivery. Despite the increased incidence of placenta accreta, most obstetricians have personally managed only a small number of women with placenta accreta. The condition poses dramatic risk for massive hemorrhage and associated complication such as consumption coagulopathy, multisystem organ failure and death. In addition, there is an increased risk for surgical complications such as injury to bladder, ureters and bowel and the need for re-operation. Most women require blood transfusion, often in large quantities, and many require admission to an intensive care unit. As a result of indicated, often emergent preterm delivery, many babies require admission to a neonatal care intensive care unit. Outcomes are improved when delivery is accomplished in centers with multi-disciplinary expertise and experience in the care of placenta accreta. Such expertise may include maternal-fetal medicine, gynecologic surgery, gynecologic oncology, vascular, trauma and urologic surgery, transfusion medicine, intensivists, neonatalogists, interventional radiologists, anesthesiologists, specialized nursing staff, and ancillary personnel. This article highlights the desired features for a center of excellence in placenta accreta, and which patients should be referred for evaluation and / or delivery in such centers.
    No preview · Article · Nov 2014 · American Journal of Obstetrics and Gynecology
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    ABSTRACT: Context: Telomere biology plays a fundamental role in genomic integrity, cellular regeneration, physiology, aging, disease risk and mortality. The initial setting of telomere length (TL) in early life has important implications for telomere maintenance and related disorders throughout the lifespan. However, little is known about the predictors of this initial setting. Objective: Given the established role of estrogen on adult TL and the role of estriol (E3) in the context of fetal development, the goal of this study was to test the hypothesis that higher maternal E3 concentration during early pregnancy is associated with longer infant telomere length. Design, Participants and Setting: Study participants comprised a cohort of N=100 infants followed prospectively from intrauterine life and birth through early childhood from a population-based, representative sample of pregnant mothers recruited in early pregnancy at university-based obstetric clinics in Southern California. Maternal unconjugated plasma (E3) concentrations were assessed in plasma in early gestation (around week 15). Infant TL was assessed in buccal cells at approximately 15 months age. Results: After accounting for the effects of potential confounding maternal and infant variables, there was a significant, independent effect of maternal E3 concentration on infant TL (unstandardized β = 0.297, p=0.001; 95% Cl: 0.121 - 0.473). Specifically, a 1 multiple-of-the-median (MoM) increase in maternal E3 concentration during early pregnancy was associated with a 14.42% increase in infant TL. Conclusions: This study supports the concept of developmental plasticity of the telomere biology system and highlights specifically the role of a potentially modifiable intrauterine factor for further mechanistic and clinical investigation.
    Full-text · Article · Oct 2014 · Journal of Clinical Endocrinology & Metabolism

  • No preview · Article · Oct 2014 · Journal of Women's Health
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    ABSTRACT: Objective To examine the association between maternal 25-hydroxyvitamin D (25(OH)D) and adverse labor and delivery outcomes. Study design We measured serum 25(OH)D at ≤26 weeks gestation in a random subsample of vertex, singleton pregnancies in women who labored (n=2798) from the 12 site Collaborative Perinatal Project (1959–66). We used labor and delivery data to classify cases of adverse outcomes. Results Twenty-four percent of women were vitamin D deficient (25(OH)D <30 nmol/L) and 4.5%, 3.3%, 1.9%, and 7.5% of women had prolonged stage 1 labor, prolonged stage 2 labor, primary cesarean delivery, or indicated instrumental delivery, respectively. After adjustment for prepregnancy BMI, race, and study site, 25(OH)D concentrations were not associated with risk of prolonged stage 1 or 2, cesarean delivery, or instrumental delivery. Conclusion Maternal vitamin D status at ≤26 weeks was not associated with risk of prolonged labor or operative delivery in an era with a low cesarean rate.
    Full-text · Article · Aug 2014 · Journal of perinatology: official journal of the California Perinatal Association
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    ABSTRACT: Background and objective: Environmental or lifestyle exposures in utero may influence the development of childhood asthma. In this meta-analysis, we aimed to assess whether maternal obesity in pregnancy (MOP) or increased maternal gestational weight gain (GWG) increased the risk of asthma in offspring. Methods: We included all observational studies published until October 2013 in PubMed, Embase, CINAHL, Scopus, The Cochrane Database, and Ovid. Random effects models with inverse variance weights were used to calculate pooled risk estimates. Results: Fourteen studies were included (N = 108 321 mother-child pairs). Twelve studies reported maternal obesity, and 5 reported GWG. Age of children was 14 months to 16 years. MOP was associated with higher odds of asthma or wheeze ever (OR = 1.31; 95% confidence interval [CI], 1.16-1.49) or current (OR = 1.21; 95% CI, 1.07-1.37); each 1-kg/m(2) increase in maternal BMI was associated with a 2% to 3% increase in the odds of childhood asthma. High GWG was associated with higher odds of asthma or wheeze ever (OR = 1.16; 95% CI, 1.001-1.34). Maternal underweight and low GWG were not associated with childhood asthma or wheeze. Meta-regression showed a negative association of borderline significance for maternal asthma history (P = .07). The significant heterogeneity among existing studies indicates a need for standardized approaches to future studies on the topic. Conclusions: MOP and high GWG are associated with an elevated risk of childhood asthma; this finding may be particularly significant for mothers without asthma history. Prospective randomized trials of maternal weight management are needed.
    Full-text · Article · Jul 2014 · Pediatrics
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    H. N. Simhan

    Preview · Article · Jul 2014 · BJOG An International Journal of Obstetrics & Gynaecology
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    Christina M Scifres · Janet M Catov · Hyagriv N Simhan
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    ABSTRACT: Objective We evaluated the impact of maternal overweight/obesity and excessive weight gain on maternal serum lipids in the first and second trimester of pregnancy. Design and Methods Prospective data were collected for 225 women. Maternal serum lipids and fatty acids were measured at <13 weeks and between 24–28 weeks. Analyses were stratified by normal weight versus overweight/obese status and excessive vs. non-excessive weight gain. Results Overweight/obese women had higher baseline cholesterol (161.3±29.6 vs 149.4±26.8 mg/dL, p<0.01), LDL (80.0±19.9 vs 72.9 ±18.8 mg/dL, p<0.01) and triglycerides ( 81.7±47.2 vs 69.7±40.3 mg/dL, p=0.05) when compared to normal weight women, while HDL (43.6 ±10.4 47.6±11.5 mg/dL, p<0.01) was lower. However, cholesterol and LDL increased at a higher weekly rate in normal weight women, resulting in higher total cholesterol in normal weight women (184.1±28.1 vs. 176.0 ±32.1 mg/dL, p=0.05) at 24–28 weeks. Excessive weight gain did not affect the rate of change in lipid profiles in either group. Overweight/obese women had higher levels of arachidonic acid at both time points. Conclusions Overweight/obese women have significantly more atherogenic lipid profiles than normal weight women during the period of early pregnancy, delineating one physiologic pathway that could explain differences in pregnancy outcomes between normal weight and overweight/obese women.
    Preview · Article · Mar 2014 · Obesity

  • No preview · Article · Jan 2014 · American Journal of Obstetrics and Gynecology

  • No preview · Article · Jan 2014 · American Journal of Obstetrics and Gynecology
  • Rosemary Froehlich · Hyagriv Simhan · Jacob Larkin

    No preview · Article · Jan 2014 · American Journal of Obstetrics and Gynecology
  • Jennifer Hutcheon · Lisa Bodnar · Hyagriv Simhan

    No preview · Article · Jan 2014 · American Journal of Obstetrics and Gynecology
  • Alison D Gernand · Hyagriv N Simhan · Steve Caritis · Lisa M Bodnar
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    ABSTRACT: To examine the association between second-trimester maternal serum 25-hydroxyvitamin D concentrations and risk of small for gestational age (SGA) in singleton live births. We assayed serum samples at 12-26 weeks of gestation for 25-hydroxyvitamin D in a sample of participants in a multicenter clinical trial of low-dose aspirin for the prevention of preeclampsia in high-risk women (n=792). Multivariable log-binomial regression models were used to assess the association between 25-hydroxyvitamin D and risk of SGA (birth weight less than the 10 percentile for gestational age) after adjustment for confounders including maternal prepregnancy obesity, race, treatment allocation, and risk group. Thirteen percent of neonates were SGA at birth. Mean (standard deviation) 25-hydroxyvitamin D concentrations were lower in women who delivered SGA (57.9 [29.9] nmol/L) compared with non-SGA neonates (64.8 [29.3] nmol/L, P=.028). In adjusted models, 25-hydroxyvitamin D concentrations of 50-74 nmol/L and 75 nmol/L or greater compared with less than 30 nmol/L were associated with 43% (95% confidence interval [CI] 0.33-0.99) and 54% (95% CI 0.24-0.87) reductions in risk of SGA, respectively. Race and maternal obesity each modified this association. White women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 68% reduction in SGA risk (adjusted risk ratio 0.32, 95% CI 0.17-0.63) and nonobese women with 25-hydroxyvitamin D 50 nmol/L or greater compared with less than 50 nmol/L had a 50% reduction in SGA risk (adjusted risk ratio 0.50, 95% CI 0.31-0.82). There was no association between 25-hydroxyvitamin D and risk of SGA in black or obese mothers. Maternal vitamin D status in the second trimester is associated with risk of SGA among all women and in the subgroups of white and nonobese women. : II.
    No preview · Article · Jan 2014 · Obstetrics and Gynecology
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    ABSTRACT: We sought to determine the association between maternal vitamin D status at ≤26 weeks' gestation and the risk of preeclampsia by clinical subtype. We conducted a case-cohort study among women enrolled at 12 US sites from 1959 to 1966 in the Collaborative Perinatal Project. In serum collected at ≤26 weeks' gestation (median 20.9 weeks) from 717 women who later developed preeclampsia (560 mild and 157 severe cases) and from 2986 mothers without preeclampsia, we measured serum 25-hydroxyvitamin D, over 40 years later, using liquid chromatography-tandem mass spectrometry. Half of women in the subcohort had 25-hydroxyvitamin D (25(OH)D) >50 nmol/L. Maternal 25(OH)D 50 to 74.9 nmol/L was associated with a reduction in the absolute and relative risk of preeclampsia and mild preeclampsia compared with 25(OH)D <30 nmol/L in the crude analysis but not after adjustment for confounders, including race, prepregnancy body mass index, and parity. For severe preeclampsia, 25(OH)D ≥50 nmol/L was associated with a reduction in three cases per 1000 pregnancies (adjusted risk difference = -0.003 [95% confidence interval = -0.005 to 0.0002]) and a 40% reduction in risk (0.65 [0.43 to 0.98]) compared with 25(OH)D <50 nmol/L. Conclusions were unchanged (1) after restricting to women with 25(OH)D measured before 22 weeks' gestation or (2) with formal sensitivity analyses for unmeasured confounding. Maternal vitamin D deficiency may be a risk factor for severe preeclampsia but not for its mild subtypes. Contemporary cohorts with large numbers of severe preeclampsia cases would be needed to confirm or refute these findings.
    No preview · Article · Jan 2014 · Epidemiology (Cambridge, Mass.)

Publication Stats

3k Citations
963.88 Total Impact Points

Institutions

  • 2003-2016
    • University of Pittsburgh
      • • Department of Obstetrics, Gynecology and Reproductive Sciences
      • • Division of General Obstetrics and Gynecology
      • • Department of Medicine
      Pittsburgh, Pennsylvania, United States
  • 2015
    • University of Pennsylvania
      Filadelfia, Pennsylvania, United States
    • McGill University
      Montréal, Quebec, Canada
  • 2002-2015
    • Magee-Womens Hospital
      • Department of Obstetrics
      Pittsburgh, Pennsylvania, United States
  • 2012
    • University of California, Irvine
      Irvine, California, United States
  • 2010
    • George Washington University
      Washington, Washington, D.C., United States
    • Eunice Kennedy Shriver National Institute of Child Health and Human Development
      Maryland, United States
  • 2008
    • University of Maryland, Baltimore
      Baltimore, Maryland, United States
  • 2007-2008
    • Columbia University
      New York, New York, United States
  • 2005
    • Duke University Medical Center
      Durham, North Carolina, United States