Bio

Clinical Focus


  • Clinical Obstetrics
  • Obstetrics and Gynecology
  • Maternal-Fetal Medicine
  • Prenatal Diagnosis

Academic Appointments


Administrative Appointments


  • Medical Director, Labor & Delivery, Lucile Packard Children's Hospital (2013 - Present)
  • Obstetrics QA Committee, Stanford University School of Medicine (2010 - 2013)
  • District IX, Section II Vice-Chair, ACOG (2011 - 2013)
  • QA Committee, District IX, ACOG (2011 - 2013)
  • Informatics Committee, SMFM (2010 - 2013)
  • Education Committee, SMFM (2011 - 2013)
  • CREOG Committee, ACOG (2011 - 2013)
  • Obstetrics Practice Committee, ACOG (2009 - 2011)
  • District IX, Junior Fellow Chair, ACOG (2008 - 2009)
  • Associate Member Representative, SMFM (2008 - 2009)

Honors & Awards


  • APGO Teaching Award, Department of Obstetrics & Gynecology, Stanford University (2012)
  • Resident Teaching Award, Department of Obstetrics & Gynecology, Stanford University (2011)
  • Outstanding Clinical Fellow, Department of Obstetrics & Gynecology, Stanford University (2008)

Professional Education


  • Residency:Mount Sinai Medical Center (2006) NY
  • Board Certification: Maternal and Fetal Medicine, American Board of Obstetrics and Gynecology (2011)
  • Board Certification: Obstetrics and Gynecology, American Board of Obstetrics and Gynecology (2008)
  • Fellowship, Stanford University, Maternal-Fetal Medicine (2009)
  • Internship:Mount Sinai Medical Center (2003) NY
  • Medical Education:Sackler School of Medicine (2002) Israel

Research & Scholarship

Current Research and Scholarly Interests


prenatal diagnosis, genetics, clinical obstetrics

Teaching

2013-14 Courses


Publications

Journal Articles


  • Oral misoprostol versus vaginal dinoprostone for labor induction in nulliparous women at term. Journal of perinatology Faucett, A. M., Daniels, K., Lee, H. C., El-Sayed, Y. Y., Blumenfeld, Y. J. 2014; 34 (2): 95-99

    Abstract

    Objective:To compare the efficacy of oral misoprostol to vaginal dinoprostone for labor induction in nulliparous women.Study design:Admissions for labor induction from January 2008 to December 2010 were reviewed. Patients receiving oral misoprostol were compared with those receiving vaginal dinoprostone. The primary outcome was time from induction agent administration to vaginal delivery. Secondary outcomes included vaginal delivery within 24 h, mode of delivery and maternal and fetal outcomes.Result:A total of 680 women were included: 483 (71%) received vaginal dinoprostone and 197 (29%) received oral misoprostol. Women who received oral misoprostol had a shorter interval to vaginal delivery (27.2 vs 21.9 h, P<0.0001) and were more likely to deliver vaginally in <24 h (47% vs 64%, P=0.001). There was no increase in the rate of cesarean delivery or adverse maternal or neonatal outcomes.Conclusion:Labor induction with oral misoprostol resulted in shorter time to vaginal delivery without increased adverse outcomes in nulliparous women.

    View details for DOI 10.1038/jp.2013.133

    View details for PubMedID 24157494

  • Isolated umbilical vein varix with a poor outcome despite close fetal surveillance. Journal of ultrasound in medicine Brookfield, K. F., Osmundson, S. S., Chetty, S., Chueh, J., Blumenfeld, Y. J., Barth, R. A., El-Sayed, Y. Y. 2013; 32 (9): 1680-1682

    View details for DOI 10.7863/ultra.32.9.1680

    View details for PubMedID 23980233

  • Maternal-fetal medicine fellowship 3- and 4-dimensional ultrasound experience: room for improvement. Journal of ultrasound in medicine Ness, A., Blumenfeld, Y. J., Platt, L. D. 2013; 32 (6): 949-953

    Abstract

    The purpose of this study was to assess maternal-fetal medicine (MFM) fellowship 3- and 4-dimensional (3D/4D) ultrasound experience and training.A 53-item prenatal diagnosis survey was emailed to 458 associate members of the Society for Maternal-Fetal Medicine. Associate members include both MFM fellows and recent graduates who are not yet board certified in MFM.A total of 148 associate members completed the survey (32% response rate); 92% were at least in their second year of a fellowship, and 48.1% had completed a fellowship. About half (50.8%) were capable of performing 3D/4D ultrasound examinations ("performers"), whereas 49.2% were not ("nonperformers"). Among performers, about 80% were capable of only basic image acquisition. Overall, 39.5% of respondents received no official 3D/4D ultrasound training, and 55.5% stated that fewer than 1 in 5 of their MFM faculty routinely performed 3D/4D ultrasound examinations. Compared with performers, nonperformers had less formal 3D/4D ultrasound training (53% versus 26%; P = .018) and fewer MFM faculty who performed 3D/4D ultrasound examinations (43% versus 68%; P = .005), and fewer nonperformers were taught by ultrasound mentors (25% versus 47.8%; P = .011).Most fellows are not trained in 3D/4D ultrasound. Greater emphasis on ultrasound mentorship and formalized ultrasound training by MFM faculty during fellowships is needed.

    View details for DOI 10.7863/ultra.32.6.949

    View details for PubMedID 23716515

  • Maternal-fetal medicine fellowship obstetrical ultrasound experience: results from a fellowship survey PRENATAL DIAGNOSIS Blumenfeld, Y. J., Ness, A., Platt, L. D. 2013; 33 (2): 158-161

    Abstract

    To assess maternal-fetal medicine (MFM) fellowship obstetrical ultrasound training, scope of practice and research.A 52-item prenatal diagnosis survey was e-mailed to 458 associate members of the Society for Maternal-Fetal Medicine on two separate occasions. Associate members include both MFM fellows and recent graduates who are not yet board certified in MFM.A total of 148 associate members completed the survey (32% response rate), 92% of whom were at least in their second year of fellowship. A total of 58% of fellows spend at least 20% of their fellowship time performing prenatal ultrasounds, and most begin their ultrasound training in their first year. Most fellows describe being comfortable performing routine fetal anatomy surveys, growth ultrasounds and umbilical artery Doppler measurements, but only 48% are nuchal translucency (NT) certified, most through Nuchal Translucency Quality Review. A total of 7% of fellows do not receive structured training in 2D ultrasound, 39% receive no structured training in 3D/4D ultrasound, and 28% receive no structured training in fetal echocardiography. Only 38% can identify an ultrasound mentor during fellowship.Most fellows are trained in ultrasound during their first year of fellowship and feel comfortable performing routine exams. However, ultrasound mentorship, structured training and research in prenatal ultrasound are limited in some programs.

    View details for DOI 10.1002/pd.4029

    View details for Web of Science ID 000314493500010

    View details for PubMedID 23229275

  • Conservatively Managed Fetal Goiter: An Alternative to in utero Therapy. Fetal diagnosis and therapy Blumenfeld, Y. J., Davis, A., Milan, K., Chueh, J., Hudgins, L., Barth, R. A., Hintz, S. R. 2013; 34 (3): 184-187

    Abstract

    Fetal goiter may arise from a variety of etiologies including iodine deficiency, overtreatment of maternal Graves' disease, inappropriate maternal thyroid replacement and, rarely, congenital hypothyroidism. Fetal goiter is often associated with a retroflexed neck and polyhydramnios, raising concerns regarding airway obstruction in such cases. Prior reports have advocated for cordocentesis and intra-amniotic thyroid hormone therapy in order to confirm the diagnosis of fetal thyroid dysfunction, reduce the size of the fetal goiter, reduce polyhydramnios, aid with the assistance of maternal thyroid hormone therapy and reduce fetal malpresentation. We report two cases of conservatively managed fetal goiter, one resulting in a vaginal delivery, and no evidence of postnatal respiratory distress despite the presence of polyhydramnios and a retroflexed neck on prenatal ultrasound. © 2013 S. Karger AG, Basel.

    View details for DOI 10.1159/000353387

    View details for PubMedID 23920148

  • Infants with Prenatally Diagnosed Anomalies Special Approaches to Preparation and Resuscitation CLINICS IN PERINATOLOGY Colby, C. E., Carey, W. A., Blumenfeld, Y. J., Hintz, S. R. 2012; 39 (4): 871-887

    Abstract

    When a fetal anomaly is suspected, a multidisciplinary approach to diagnosis, counseling, pregnancy management, surveillance, delivery planning, and neonatal care is critical to creating a comprehensive management plan. This article provides a basic framework for integrating prenatal diagnostic and maternal-fetal care considerations, delivery planning, special resuscitation needs, and immediate and later neonatal care and evaluation into developing a thoughtful management plan for infants with prenatally diagnosed complex anomalies including congenital heart disease, intrathoracic masses, fetal airway obstruction, neural tube defects, abdominal wall defects, and skeletal dysplasia.

    View details for DOI 10.1016/j.clp.2012.09.012

    View details for Web of Science ID 000312623900011

    View details for PubMedID 23164184

  • Utilization of available prenatal screening and diagnosis: effects of the California screen program JOURNAL OF PERINATOLOGY Blumenfeld, Y. J., Taylor, J., Lee, H. C., Hudgins, L., Sung, J. F., El-Sayed, Y. Y. 2012; 32 (12): 907-912

    Abstract

    In 2009, the California Genetic Disease Branch introduced an aneuploidy screening program allowing Medi-Cal (state insured) patients access to state-sponsored first-trimester screening. The objective of this study was to assess the effect of greater access to prenatal screening on available resources at a single center.Data of prenatal screening and diagnostic procedures performed 4 months before the introduction of the program were compared with those of 12 months following the introduction.Between December 2008 and March 2010, 7689 women underwent first trimester screening, 1286 underwent amniocentesis and 398 underwent chorionic villus sampling. When a comparison was made between the 4 months before and the 12 months after the program's introduction, a greater number of nuchal translucency (NT) examinations was seen to have been performed (384 per month vs 513 per month, P=0.001). Prenatal diagnostic procedures did not increase, but a greater proportion was performed for positive screen results.Introduction of the California screening program was associated with increased NT procedures and fewer invasive procedures for advanced maternal age.

    View details for DOI 10.1038/jp.2012.8

    View details for Web of Science ID 000311831700002

    View details for PubMedID 22402484

  • Non-invasive prenatal measurement of the fetal genome NATURE Fan, H. C., Gu, W., Wang, J., Blumenfeld, Y. J., El-Sayed, Y. Y., Quake, S. R. 2012; 487 (7407): 320-?

    Abstract

    The vast majority of prenatal genetic testing requires invasive sampling. However, this poses a risk to the fetus, so one must make a decision that weighs the desire for genetic information against the risk of an adverse outcome due to hazards of the testing process. These issues are not required to be coupled, and it would be desirable to discover genetic information about the fetus without incurring a health risk. Here we demonstrate that it is possible to non-invasively sequence the entire prenatal genome. Our results show that molecular counting of parental haplotypes in maternal plasma by shotgun sequencing of maternal plasma DNA allows the inherited fetal genome to be deciphered non-invasively. We also applied the counting principle directly to each allele in the fetal exome by performing exome capture on maternal plasma DNA before shotgun sequencing. This approach enables non-invasive exome screening of clinically relevant and deleterious alleles that were paternally inherited or had arisen as de novo germline mutations, and complements the haplotype counting approach to provide a comprehensive view of the fetal genome. Non-invasive determination of the fetal genome may ultimately facilitate the diagnosis of all inherited and de novo genetic disease.

    View details for DOI 10.1038/nature11251

    View details for Web of Science ID 000306506500033

    View details for PubMedID 22763444

  • Trends in Cesarean Delivery for Twin Births in the United States: 1995-2008 Reply OBSTETRICS AND GYNECOLOGY Lee, H. C., Gould, J. B., Boscardin, W. J., El-Sayed, Y. Y., Blumenfeld, Y. J. 2012; 119 (3): 658-659
  • Erratum: Non-invasive prenatal measurement of the fetal genome. Nature Fan, H. C., Gu, W., Wang, J., Blumenfeld, Y. J., El-Sayed, Y. Y., Quake, S. R. 2012

    View details for PubMedID 22878723

  • Noninvasive prenatal diagnosis: pregnant women's interest and expected uptake PRENATAL DIAGNOSIS Tischler, R., Hudgins, L., Blumenfeld, Y. J., Greely, H. T., Ormond, K. E. 2011; 31 (13): 1292-1299

    Abstract

    To investigate pregnant women's level of future interest in noninvasive prenatal diagnosis (NIPD) and what factors might affect expected uptake of this testing.Written questionnaires were administered to women in their third trimester.One hundred fourteen women returned the questionnaire (80.9% response rate). Of these, 71.9% reported interest in NIPD, 22.7% were ambivalent, and 5.4% were uninterested. Safety of the fetus was the single most important factor in 75% of women's decisions. Factors associated with increased interest in NIPD included: older age (p?=?0.036), higher education (p?=?0.013), Caucasian or Asian ethnicity (p?=?0.011), and higher likelihood to terminate an affected pregnancy (p?=?0.002). Nearly 20% of women reported that they would do whatever their doctor recommended regarding NIPD, and 94.4% of women wished to meet with a genetic counselor at some point to discuss NIPD.The majority of pregnant women report hypothetical interest in NIPD, primarily because of increased safety for the fetus, although a significant minority are uninterested or ambivalent. Discussions with healthcare providers regarding NIPD, and their recommendations, are likely to be an important factor in women's decisions about this testing. As such, adequate discussion of the implications of prenatal diagnostic testing will be critical.

    View details for DOI 10.1002/pd.2888

    View details for Web of Science ID 000298566900013

    View details for PubMedID 22028097

  • Trends in Cesarean Delivery for Twin Births in the United States 1995-2008 OBSTETRICS AND GYNECOLOGY Lee, H. C., Gould, J. B., Boscardin, W. J., El-Sayed, Y. Y., Blumenfeld, Y. J. 2011; 118 (5): 1095-1101

    Abstract

    To estimate trends and risk factors for cesarean delivery for twins in the United States.This was a cross-sectional study in which we calculated cesarean delivery rates for twins from 1995 to 2008 using National Center for Health Statistics data. We compared cesarean delivery rates by year and for vertex compared with breech presentation. The order of presentation for a given twin pair could not be determined from the available records and therefore analysis was based on individual discrete twin data. Multivariable logistic regression was used to estimate independent risk factors, including year of birth and maternal factors, for cesarean delivery.Cesarean delivery rates for twin births increased steadily from 53.4% to 75.0% in 2008. Rates rose for the breech twin category (81.5%-92.1%) and the vertex twin category (45.1%-68.2%). The relative increase in the cesarean delivery rate for preterm and term neonates was similar. After risk adjustment, there was an average increase noted in cesarean delivery of 5% each year during the study period (risk ratio 1.05, 95% confidence interval 1.04-1.05).Cesarean delivery rates for twin births increased dramatically from 1995 to 2008. This increase is significantly higher than that which could be explained by an increase in cesarean delivery for breech presentation of either the presenting or second twin.

    View details for DOI 10.1097/AOG.0b013e3182318651

    View details for Web of Science ID 000296292600018

    View details for PubMedID 22015878

  • Sextuplet heterotopic pregnancy presenting as ovarian hyperstimulation syndrome and hemoperitoneum FERTILITY AND STERILITY Fisher, S. L., Massie, J. A., Blumenfeld, Y. J., Lathi, R. B. 2011; 95 (7)

    Abstract

    To describe a case of bilateral ruptured heterotopic pregnancies presenting as persistent ovarian hyperstimulation syndrome in a quadruplet pregnancy.Case report.University hospital and clinic.An infertile patient who conceived using gonadotropin therapy.Culdocentesis with resultant aspiration of sanguinous fluid prompted laparoscopic exploration and bilateral salpingectomies.Not applicable.Gross hemoperitoneum and ruptured bilateral heterotopic sextuplet pregnancy.Patients who conceive after gonadotropin therapy should be closely monitored during treatment and in early pregnancy to recognize and minimize morbidity and complications. After superovulation, the presence of an intrauterine pregnancy, either single or multiple, does not rule out the possibility of ectopic pregnancy, and this should always be considered as a possibility in the setting of acute anemia.

    View details for DOI 10.1016/j.fertnstert.2011.01.172

    View details for Web of Science ID 000290791000088

    View details for PubMedID 21406303

  • Prenatal Diagnosis of Cross-Fused Renal Ectopia: Does Color Doppler and 3-Dimensional Sonography Help? JOURNAL OF ULTRASOUND IN MEDICINE Chang, P. L., Mrazek-Pugh, B., Blumenfeld, Y. J. 2011; 30 (4): 578-580

    View details for Web of Science ID 000291126800019

    View details for PubMedID 21460160

  • MR imaging in cases of antenatal suspected appendicitis - a meta-analysis JOURNAL OF MATERNAL-FETAL & NEONATAL MEDICINE Blumenfeld, Y. J., Wong, A. E., Jafari, A., Barth, R. A., El-Sayed, Y. Y. 2011; 24 (3): 485-488

    Abstract

    Appendicitis is the most common surgical emergency in pregnancy. Acute appendicitis is often difficult to diagnose clinically, and concerns regarding antenatal CT imaging limit its use resulting in high false negative rates at laparotomy. MRI has recently been reported as a reasonable alternative to CT imaging in cases of suspected appendicitis. Our objective was to perform a meta-analysis of recently published data regarding the utility of MR imaging in cases of antenatal suspected acute appendicitis.We searched the PubMed database using keywords 'MRI', 'appendicitis', and 'pregnancy'. Five case series describing the role of MRI in cases of antenatal appendicitis were included. The sensitivity, specificity, positive, and negative predictive values were calculated.Two hundred twenty-nine patients were included in the study. In the first analysis in which non-diagnostic scans were excluded, the sensitivity, specificity, positive and negative predictive values of MRI for diagnosing appendicitis were 95.0%, 99.9%, 90.4%, and 99.5%, respectively. In the second analysis, which included non-diagnostic scans, the sensitivity, specificity, positive and negative predictive values were 90.5%, 98.6%, 86.3%, and 99.0%, respectivelyMR imaging may be useful in cases of suspected antenatal appendicitis. Data are still limited and larger prospective studies are necessary to confirm this finding.

    View details for DOI 10.3109/14767058.2010.506227

    View details for Web of Science ID 000286993000020

    View details for PubMedID 20695758

  • Antenatal Steroid Administration for Premature Neonates in California OBSTETRICS AND GYNECOLOGY Lee, H. C., Lyndon, A., Blumenfeld, Y. J., Dudley, R. A., Gould, J. B. 2011; 117 (3): 603-609

    Abstract

    To estimate risk factors for premature neonates not receiving antenatal steroids in a population-based cohort and to determine whether the gains of a quality-improvement collaborative project on antenatal steroid administration were sustained long-term.Clinical data for premature neonates born in 2005–2007 were obtained from the California Perinatal Quality Care Collaborative, which collects data on more than 90% of neonatal admissions in California. Eligible neonates had a birth weight of less than 1,500 g or gestational age less than 34 weeks and were born at a Collaborative hospital. These data were linked to administrative data from California Vital Statistics. Sociodemographic and medical risk factors for not receiving antenatal steroids were determined. We also examined the effect of birth hospital participation in a previous quality-improvement collaborative project. A random effects logistic regression model was used to determine independent risk factors.Of 15,343 eligible neonates, 23.1% did not receive antenatal steroids in 2005–2007. Hispanic mothers (25.6%), mothers younger than age 20 (27.6%), and those without prenatal care (52.2%) were less likely to receive antenatal steroids. Mothers giving birth vaginally (26.8%) and mothers with a diagnosis of fetal distress (26.5%) were also less likely to receive antenatal steroids. Rupture of membranes before delivery and multiple gestations were associated with higher likelihood of antenatal steroid administration. Hospitals that participated in a quality-improvement collaborative in 1999– 2000 had higher rates of antenatal steroid administration (85% compared with 69%, P<.001).A number of eligible mothers do not receive antenatal steroids. Quality-improvement initiatives to improve antenatal steroid administration could target specific high-risk groups.

    View details for DOI 10.1097/AOG.0b013e31820c3c9b

    View details for Web of Science ID 000287649400013

    View details for PubMedID 21446208

  • Maternal-fetal and neonatal pharmacogenomics: a review of current literature JOURNAL OF PERINATOLOGY Blumenfeld, Y. J., Reynolds-May, M. F., Altman, R. B., El-Sayed, Y. Y. 2010; 30 (9): 571-579

    Abstract

    Pharmacogenomics, the study of specific genetic variations and their effect on drug response, will likely give rise to many applications in maternal-fetal and neonatal medicine; yet, an understanding of these applications in the field of obstetrics and gynecology and neonatal pediatrics is not widespread. This review describes the underpinnings of the field of pharmacogenomics and summarizes the current pharmacogenomic inquiries in relation to maternal-fetal medicine-including studies on various fetal and neonatal genetic cytochrome P450 (CYP) enzyme variants and their role in drug toxicities (for example, codeine metabolism, sepsis and selective serotonin reuptake inhibitor (SSRI) toxicity). Potential future directions, including alternative drug classification, improvements in drug efficacy and non-invasive pharmacogenomic testing, will also be explored.

    View details for DOI 10.1038/jp.2009.183

    View details for Web of Science ID 000281388500002

    View details for PubMedID 19924131

  • Analysis of the Size Distributions of Fetal and Maternal Cell-Free DNA by Paired-End Sequencing CLINICAL CHEMISTRY Fan, H. C., Blumenfeld, Y. J., Chitkara, U., Hudgins, L., Quake, S. R. 2010; 56 (8): 1279-1286

    Abstract

    Noninvasive prenatal diagnosis with cell-free DNA in maternal plasma is challenging because only a small portion of the DNA sample is derived from the fetus. A few previous studies provided size-range estimates of maternal and fetal DNA, but direct measurement of the size distributions is difficult because of the small quantity of cell-free DNA.We used high-throughput paired-end sequencing to directly measure the size distributions of maternal and fetal DNA in cell-free maternal plasma collected from 3 typical diploid and 4 aneuploid male pregnancies. As a control, restriction fragments of lambda DNA were also sequenced.Cell-free DNA had a dominant peak at approximately 162 bp and a minor peak at approximately 340 bp. Chromosome Y sequences were rarely longer than 250 bp but were present in sizes of <150 bp at a larger proportion compared with the rest of the sequences. Selective analysis of the shortest fragments generally increased the fetal DNA fraction but did not necessarily increase the sensitivity of aneuploidy detection, owing to the reduction in the number of DNA molecules being counted. Restriction fragments of lambda DNA with sizes between 60 bp and 120 bp were preferentially sequenced, indicating that the shotgun sequencing work flow introduced a bias toward shorter fragments.Our results confirm that fetal DNA is shorter than maternal DNA. The enrichment of fetal DNA by size selection, however, may not provide a dramatic increase in sensitivity for assays that rely on length measurement in situ because of a trade-off between the fetal DNA fraction and the number of molecules being counted.

    View details for DOI 10.1373/clinchem.2010.144188

    View details for Web of Science ID 000280501400016

    View details for PubMedID 20558635

  • Ultrasound estimation of fetal weight in small for gestational age pregnancies JOURNAL OF MATERNAL-FETAL & NEONATAL MEDICINE Blumenfeld, Y. J., Lee, H. C., Pullen, K. M., Wong, A. E., Pettit, K., Taslimi, M. M. 2010; 23 (8): 790-793

    Abstract

    Approximately half of small for gestational age (SGA) cases are due to maternal or fetal pathology, and may result in significant neonatal morbidity and mortality. The estimated fetal weight (EFW) measurement is the cornerstone of ultrasonographic findings when diagnosing and managing SGA pregnancies. Our objective was to determine the ultrasound accuracy of EFW in SGA pregnancies.A retrospective chart review was performed of all pregnancies complicated by SGA from a single institution (Stanford University) over a 2-year-period (2004-2006). SGA was defined as EFW < or = 10%. 98 neonates whose last ultrasound for EFW occurred within 7 days of delivery were included in the study. The absolute differences between the EFW and birthweight (BW) were analyzed, and the absolute percent errors were calculated as (EFW - BW)/BW x 100. The mean absolute differences and mean absolute percent errors were analyzed across all gestational ages (GA) and EFWs using one-way analysis of variance.The mean absolute percent error for the entire cohort was 8.7% (+/-6.3%). There was no statistically significant difference in the mean absolute percent error across all GAs (<32 weeks, 32-36 weeks, >36 weeks), and EFWs (<1500 g, 1500-2000 g, >2000 g).Ultrasound measurement of EFW in SGA pregnancies is consistent across all GAs and EFW measurements.

    View details for DOI 10.3109/14767050903387052

    View details for Web of Science ID 000280592200006

    View details for PubMedID 19968588

  • Single- versus double-layer hysterotomy closure at primary caesarean delivery and bladder adhesions BJOG-AN INTERNATIONAL JOURNAL OF OBSTETRICS AND GYNAECOLOGY Blumenfeld, Y. J., Caughey, A. B., El-Sayed, Y. Y., Daniels, K., Lyell, D. J. 2010; 117 (6): 690-694

    Abstract

    To determine the association between single-layer (one running suture) and double-layer (second layer or imbricating suture) hysterotomy closure at primary caesarean delivery and subsequent adhesion formation.A secondary analysis from a prospective cohort study of women undergoing first repeat caesarean section.Department of Obstetrics and Gynecology, Stanford University, Stanford, CA, USA.One hundred and twenty-seven pregnant women undergoing first repeat caesarean section.Patient records were reviewed to identify whether primary caesarean hysterotomies were closed with a single or double layer. Data were analysed by Fisher's exact tests and multivariable logistic regression.Prevalence rate of pelvic and abdominal adhesions.Of the 127 women, primary hysterotomy closure was single layer in 56 and double layer in 71. Single-layer hysterotomy closure was associated with bladder adhesions at the time of repeat caesarean (24% versus 7%, P = 0.01). Single-layer closure was associated in this study with a seven-fold increase in the odds of developing bladder adhesions (odds ratio, 6.96; 95% confidence interval, 1.72-28.1), regardless of other surgical techniques, previous labour, infection and age over 35 years. There was no association between single-layer closure and other pelvic or abdominal adhesions.Primary single-layer hysterotomy closure may be associated with more frequent bladder adhesions during repeat caesarean deliveries. The severity and clinical implications of these adhesions should be assessed in large prospective trials.

    View details for DOI 10.1111/j.1471-0528.2010.02529.x

    View details for Web of Science ID 000276509100007

    View details for PubMedID 20236104

  • The Effects of Respiratory Failure on Delivery in Pregnant Patients With H1N1 2009 Influenza OBSTETRICS AND GYNECOLOGY Jafari, A., Langen, E. S., Aziz, N., Blumenfeld, Y. J., Mihm, F., Druzin, M. L. 2010; 115 (5): 1033-1035

    Abstract

    The majority of hospitalizations for H1N1 complications have been in people with high-risk comorbidities, including pregnancy. Here we describe the obstetric and critical care treatment of three patients with confirmed H1N1 influenza virus infection complicated by acute respiratory failure.We describe the clinical and therapeutic courses of three patients with confirmed H1N1 2009 influenza virus infection complicating singleton, twin, and triplet gestations, each of which were complicated by respiratory failure.These three cases illustrate that a high index of suspicion, prompt treatment, timing and mode of delivery considerations, and interdisciplinary treatment are integral to the care of pregnant patients with H1N1 influenza infections complicated by acute respiratory failure.

    View details for DOI 10.1097/AOG.0b013e3181da85fc

    View details for Web of Science ID 000277185800022

    View details for PubMedID 20410779

  • Chorionic villus sampling: technique and training CURRENT OPINION IN OBSTETRICS & GYNECOLOGY Blumenfeld, Y. J., Chueh, J. 2010; 22 (2): 146-151

    Abstract

    Over the past decade, first trimester screening has become the gold standard prenatal screening modality in the developed world. This shift toward earlier screening would not be possible without the availability of early diagnosis, namely, chorionic villus sampling (CVS). The purpose of this review is to highlight recent updates related to CVS technique, potential complications, and training.Recent data highlight the importance of operator experience in reducing CVS-related complications and argues for the 'centralization' of CVS in experienced centers. On the other hand, despite over 30 years of clinical practice, there is still no consensus regarding optimal CVS technique and some variation exists between CVS providers. Moreover, there is a deficiency in adequate infrastructure geared toward the training and certification of future CVS providers.CVS is the gold standard method of first trimester prenatal diagnosis. Recent data suggest that CVS loss rates are lower than what was previously reported and are lowest in centers that perform a large number of procedures. The 'centralization' of this specialized procedure also offers the perfect opportunity for the safe, ongoing training of future CVS providers.

    View details for DOI 10.1097/GCO.0b013e3283372365

    View details for Web of Science ID 000276562900010

    View details for PubMedID 20154617

  • Microfluidic digital PCR enables rapid prenatal diagnosis of fetal aneuploidy AMERICAN JOURNAL OF OBSTETRICS AND GYNECOLOGY Fan, H. C., Blumenfeld, Y. J., El-Sayed, Y. Y., Chueh, J., Quake, S. R. 2009; 200 (5)

    Abstract

    The purpose of this study was to demonstrate that digital polymerase chain reaction (PCR) enables rapid, allele independent molecular detection of fetal aneuploidy.Twenty-four amniocentesis and 16 chorionic villus samples were used for microfluidic digital PCR analysis. Three thousand and sixty PCR reactions were performed for each of the target chromosomes (X, Y, 13, 18, and 21), and the number of single molecule amplifications was compared to a reference. The difference between target and reference chromosome counts was used to determine the ploidy of each of the target chromosomes.Digital PCR accurately identified all cases of fetal trisomy (3 cases of trisomy 21, 3 cases of trisomy 18, and 2 cases of triosmy 13) in the 40 specimens analyzed. The remaining specimens were determined to have normal ploidy for the chromosomes tested.Microfluidic digital PCR allows detection of fetal chromosomal aneuploidy utilizing uncultured amniocytes and chorionic villus tissue in less than 6 hours.

    View details for DOI 10.1016/j.ajog.2009.03.002

    View details for Web of Science ID 000265253800029

    View details for PubMedID 19375573

  • Prematurity prevention: the role of acute tocolysis CURRENT OPINION IN OBSTETRICS & GYNECOLOGY Blumenfeld, Y. J., Lyell, D. J. 2009; 21 (2): 136-141

    Abstract

    The preterm birth rate in the United States remains at an all-time high and continues to rise. Acute tocolysis has potential to delay preterm birth for 48 h, the critical period of antenatal steroid administration, or to arrest an episode of preterm labor, thus delaying birth and improving neonatal outcomes. It is therefore paramount that medical providers remain up-to-date regarding the usefulness, indications and contraindications, and side-effects and adverse effects of all tocolytics.Magnesium sulfate remains the most common tocolyic agent in the United States. Recent evidence comparing oral nifedipine with magnesium sulfate suggests equal efficacy with fewer maternal side-effects, thus supporting this oral medication as first-line treatment. This review will summarize the most common acute tocolytic drugs, their methods of action, and clinical data regarding their utility.All tocolytic medications have side-effects, some of them potentially life-threatening. Decisions regarding whether to use a tocolytic and which tocolytic to use require the diagnosis of preterm labor, knowledge of the patient's gestational age, medical conditions, and cost. Once tocolysis is initiated, attention must be paid to the patient's response, side-effects, and adverse events. Larger studies are needed which incorporate, in addition to efficacy, data on safety and side-effect profiles and cost.

    View details for DOI 10.1097/GCO.0b013e3283292455

    View details for Web of Science ID 000265320800006

    View details for PubMedID 19996866

  • Noninvasive diagnosis of fetal aneuploidy by shotgun sequencing DNA from maternal blood PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA Fan, H. C., Blumenfeld, Y. J., Chitkara, U., Hudgins, L., Quake, S. R. 2008; 105 (42): 16266-16271

    Abstract

    We directly sequenced cell-free DNA with high-throughput shotgun sequencing technology from plasma of pregnant women, obtaining, on average, 5 million sequence tags per patient sample. This enabled us to measure the over- and underrepresentation of chromosomes from an aneuploid fetus. The sequencing approach is polymorphism-independent and therefore universally applicable for the noninvasive detection of fetal aneuploidy. Using this method, we successfully identified all nine cases of trisomy 21 (Down syndrome), two cases of trisomy 18 (Edward syndrome), and one case of trisomy 13 (Patau syndrome) in a cohort of 18 normal and aneuploid pregnancies; trisomy was detected at gestational ages as early as the 14th week. Direct sequencing also allowed us to study the characteristics of cell-free plasma DNA, and we found evidence that this DNA is enriched for sequences from nucleosomes.

    View details for DOI 10.1073/pnas.0808319105

    View details for Web of Science ID 000260597400037

    View details for PubMedID 18838674

  • Single- versus double-layer uterine incision closure and uterine rupture JOURNAL OF MATERNAL-FETAL & NEONATAL MEDICINE Gyamfi, C., Juhasz, G., Gyamfi, P., Blumenfeld, Y., Stone, J. L. 2006; 19 (10): 639-643

    Abstract

    To evaluate whether closure of the uterine incision with one or two layers changes uterine rupture or vaginal birth after cesarean section (VBAC) success rates.Subjects with one previous cesarean section by documented transverse uterine incision that attempted VBAC were identified. Exclusion criteria included lack of documentation of the type of closure of the previous uterine incision, multiple gestation, more than one previous cesarean section, and previous scar other than low transverse. Uterine rupture and VBAC success rates were compared between those with single-layer and double-layer uterine closure. Time interval between deliveries, birth weight, body mass index (BMI), and history of previous VBAC were evaluated as possible confounders.Of 948 subjects identified, 913 had double-layer closure and 35 had single-layer closure. The uterine rupture rate was significantly higher in the single-layer closure group (8.6% vs. 1.3%, p = 0.015). This finding persisted when controlling for previous VBAC, induction, birth weight >4000 g, delivery interval >19 months, and BMI >29 (OR 8.01, 95% CI 1.96-32.79). There was no difference in VBAC success rate (74.3% vs. 77%, p = 0.685).Single-layer uterine closure may be more likely to result in uterine rupture.

    View details for DOI 10.1080/14767050600849383

    View details for Web of Science ID 000242992000007

    View details for PubMedID 17118738

  • Fetal urinoma as a sign of a dysplastic kidney PEDIATRIC NEPHROLOGY Miller, M., Korzets, Z., Blumenfeld, Y., Pomeranz, M., Aviram, R., Rathaus, V., Pomeranz, A. 2003; 18 (1): 65-67

    Abstract

    We describe a female neonate in whom a urinoma was first diagnosed at 20 weeks of gestation without any evidence of underlying urinary tract obstruction. The urinoma became apparent following the performance of a "bloody tap" amniocentesis. Sequential ultrasonography, both fetal and up to 3 months after birth, showed eventual resorption of the urinoma in parallel with the development of a shrunken, non-functioning kidney. Except for the onset of high-renin hypertension, which spontaneously remitted at 1 year of age, the baby's postnatal course was uneventful. Renal function was normal. The presence of a fetal urinoma as a sign of a dysplastic kidney is discussed.

    View details for DOI 10.1007/s00467-002-0862-x

    View details for Web of Science ID 000180591500014

    View details for PubMedID 12488994

Conference Proceedings


  • Rectus muscle and visceral peritoneum closure at cesarean delivery and intraabdominal adhesions Lyell, D. J., Caughey, A. B., Hu, E., Blumenfeld, Y., El-Sayed, Y. Y., Daniels, K. MOSBY-ELSEVIER. 2012

    Abstract

    The purpose of this study was to evaluate the effect of the rectus muscle and visceral peritoneum closure at cesarean delivery on adhesions.We performed a secondary analysis of a prospective cohort study of women who underwent first repeat cesarean delivery. Surgeons scored the severity and location of adhesions. Records were abstracted to assess previous surgical techniques.The original cohort included 173 patients. Rectus muscle closure was associated with fewer combined filmy and dense adhesions overall (27.5% vs 46%; P = .04) and fewer dense adhesions overall (17.5% vs 46%; P = .001; adjusted odds ratio, [aOR], 0.24; 95% confidence interval [CI], 0.09-0.65), particularly from fascia to omentum (aOR, 0.08; 95% CI, 0.007-0.82). Visceral peritoneum closure was associated with increased dense fascia-to-omentum adhesions (aOR, 15.78; 95% CI, 1.81-137.24).Closure of the rectus muscles at cesarean delivery may reduce adhesions, and visceral peritoneum closure may increase them. Surgical techniques at cesarean delivery should be assessed independently, because they may have opposite effects on adhesion formation.

    View details for DOI 10.1016/j.ajog.2012.02.033

    View details for Web of Science ID 000304442900029

    View details for PubMedID 22463952

  • Do adhesions at repeat cesarean delay delivery of the newborn? Greenberg, M. B., Daniels, K., Blumenfeld, Y. J., Caughey, A. B., Lyell, D. J. MOSBY-ELSEVIER. 2011

    Abstract

    We sought to assess whether the presence and severity of adhesions at first repeat cesarean delivery are associated with delayed delivery of the newborn.We conducted secondary analysis of a prospective cohort of women undergoing first repeat cesarean. Severity and location of adhesions were reported by surgeons immediately postoperatively. We compared adhesion density scores with delivery data.Of 145 women analyzed, 92 (63.5%) had adhesions and 53 (36.5%) did not. Mean incision to delivery time in women with adhesion scores >3 was 19.8 minutes, compared to 15.6 minutes with scores ? 3 (P = .04). More women with adhesion scores >3 remained undelivered at 30 minutes after incision compared to scores ? 3 (17.9% vs 5.1%; odds ratio, 7.6; 95% confidence interval, 1.6-34.5), after controlling for potential confounders.Among women undergoing first repeat cesarean, severity of adhesions may delay delivery of the newborn. Study of techniques to reduce adhesions may be warranted to prevent delayed delivery at repeat cesarean.

    View details for DOI 10.1016/j.ajog.2011.06.088

    View details for Web of Science ID 000296084600050

    View details for PubMedID 21864825

  • The Effect of Preterm Premature Rupture of Membranes on Neonatal Mortality Rates Blumenfeld, Y. J., Lee, H. C., Gould, J. B., Langen, E. S., Jafari, A., El-Sayed, Y. Y. LIPPINCOTT WILLIAMS & WILKINS. 2010: 1381-1386

    Abstract

    To estimate the effect of preterm premature rupture of membranes (PROM) on neonatal mortality.A cross-sectional study using a state perinatal database (California Perinatal Quality Care Collaborative) was performed. Prenatal data, including ruptured membranes, corticosteroid administration, maternal age, maternal race, maternal hypertension, mode of delivery, and prenatal care, were recorded. Mortality rates were compared for neonates born between 24 and 34 weeks of gestation without preterm PROM to those with recent (less than 18 hours before delivery) and prolonged (more than 18 hours before delivery) preterm PROM. Neonatal sepsis rates were also examined.Neonates born between 24 0/7 and 34 0/7 weeks of gestation from 127 California neonatal intensive care units between 2005 and 2007 were included (N=17,501). When analyzed by 2-week gestational age groups, there were no differences in mortality rates between those born with and without membrane rupture before delivery. The presence of prolonged preterm PROM was associated with decreased mortality at 24 to 26 weeks of gestation (18% compared with 31% for recent preterm PROM; odds ratio [OR] 1.79; confidence interval [CI] 1.25-2.56) but increased mortality at 28 to 30 weeks of gestation (4% compared with 3% for recent preterm PROM; OR 0.44; CI 0.22, 0.88) when adjusted for possible confounding factors. Sepsis rates did not differ between those with recent or prolonged preterm PROM at any gestational age.The presence of membrane rupture before delivery was not associated with increased neonatal mortality in any gestational age group. The effects of a prolonged latency period were not consistent across gestational ages.

    View details for DOI 10.1097/AOG.0b013e3181fe3d28

    View details for Web of Science ID 000284491000021

    View details for PubMedID 21099606

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