Juan Vargas
University of California, San Francisco
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Publication
Featured researches published by Juan Vargas.
British Journal of Obstetrics and Gynaecology | 2006
A. C. E. Angeja; A. E. Washington; Juan Vargas; Ricardo Gomez; I. Rojas; Aaron B. Caughey
Objective Caesarean section rates in Chile are reported to be as high as 60% in some populations. The purpose of this study was to determine pregnant Chilean women’s preferences towards mode of delivery.
Obstetrics & Gynecology | 2010
Shani Delaney; Brian L Shaffer; Yvonne W. Cheng; Juan Vargas; Teresa N. Sparks; Kathleen Paul; Aaron B. Caughey
OBJECTIVE: To compare 30-mL and 60-mL Foley balloon inflation for labor induction and the effect on length of labor and mode of delivery. METHODS: Women with term, vertex, singleton pregnancies (n=192) and a Bishop score less than 5 were assigned randomly to receive a transcervical Foley balloon inflated to either 30 mL or 60 mL. Exclusion criteria were painful, regular contractions on admission, ruptured membranes, low-lying placenta, or prior hysterotomy. Randomization was stratified by parity, and health care providers were blinded to Foley balloon size. Primary outcome was delivery within 24 hours of Foley balloon placement. Secondary outcomes included delivery within 12 hours, time from Foley balloon placement to expulsion, cervical dilation after Foley balloon expulsion, maximum oxytocin dose, method of delivery, chorioamnionitis, meconium, cervical laceration, abruption, 5-minute Apgar score, and umbilical cord gases. RESULTS: A higher proportion of women randomly assigned to the 60-mL Foley balloon achieved delivery within 12 hours of placement compared with the 30-mL Foley balloon group (26% compared with 14%, P=.04). This difference was more pronounced among nulliparous women. There was no difference in median time interval to delivery or proportion of women who achieved delivery within 24 hours. Median cervical dilation after Foley balloon expulsion was higher in the 60-mL Foley balloon group (4 cm compared with 3 cm, P<.01). There were no differences in the frequencies of cesarean delivery, maternal morbidity, or neonatal outcomes. CONCLUSION: Labor induction using Foley balloons inflated to 60 mL was more likely to achieve delivery within 12 hours compared with 30-mL inflation. There were no differences in delivery within 24 hours, cesarean delivery, labor complications, or neonatal outcomes. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00451308. LEVEL OF EVIDENCE: I
PLOS ONE | 2012
Michelle Rook; Juan Vargas; Aaron B. Caughey; Peter Bacchetti; Philip J. Rosenthal; Laura N. Bull
Background Intrahepatic cholestasis of pregnancy (ICP) has important fetal implications. There is increased risk for poor fetal outcomes, including preterm delivery, meconium staining of amniotic fluid, respiratory distress, fetal distress and demise. Methods One hundred and one women diagnosed with ICP between January 2005 and March 2009 at San Francisco General Hospital were included in this study. Single predictor logistic regression models were used to assess the associations of maternal clinical and biochemical predictors with fetal complications. Clinical predictors analyzed included age, race/ethnicity, gravidity, parity, history of liver or biliary disease, history of ICP in previous pregnancies, and induction. Biochemical predictors analyzed included serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, total bilirubin, direct bilirubin, albumin, total protein, and total bile acids (TBA). Results The prevalence of ICP was 1.9%. Most were Latina (90%). Labor was induced in the majority (87%) and most were delivered by normal spontaneous vaginal delivery (84%). Fetal complications occurred in 33% of the deliveries, with respiratory distress accounting for the majority of complications. There were no statistically significant clinical or biochemical predictors associated with an increased risk of fetal complications. Elevated TBA had little association with fetal complications until reaching greater than 100 µmoL/L, with 3 out of 5 having reported complications. ICP in previous pregnancies was associated with decreased risk of fetal complications (OR 0.21, p = 0.046). There were no cases of late term fetal demise. Conclusions Maternal clinical and laboratory features, including elevated TBA, did not appear to be substantial predictors of fetal complications in ICP.
Journal of Maternal-fetal & Neonatal Medicine | 2011
Brian L Shaffer; Yvonne W. Cheng; Juan Vargas; Aaron B. Caughey
Objective. To examine mode of delivery and perinatal outcomes in women with occiput posterior (OP) or transverse (OT) position in the second stage of labour with a trial of manual rotation compared to expectant management. Methods. A retrospective cohort study was designed to examine mode of delivery and perinatal morbidity in women who underwent a trial of manual rotation (n = 731) compared to expectant management (n = 2527) during the second stage of labour with the fetus in OP/OT position. Chi-square test was used to compare categorical outcomes and multivariable logistic regression models were used to control for potential confounders. Results. Compared to expectant management, women with manual rotation were less likely to have: caesarean delivery (CD) [adjusted odds ratio (aOR) 0.12; 95% confidence interval (CI) 0.09–0.16], severe perineal laceration [aOR 0.64; (0.47–0.88)], postpartum haemorrhage [aOR 0.75; (0.62–0.98)], and chorioamnionitis [aOR 0.68; (0.50–0.92)]. The number of rotations attempted to avert one CD was 4. In contrast, women who had a trial of rotation had an increased risk of cervical laceration [aOR 2.46; (1.1–5.4)]. Conclusions. Compared with expectant management, a trial of manual rotation with persistent fetal OP/OT position is associated with a reduction in CD and adverse maternal outcomes.
Obstetrics & Gynecology | 2008
Jody Steinauer; Justin T. Diedrich; Mark W. Wilson; Philip D. Darney; Juan Vargas; Eleanor A. Drey
OBJECTIVE: To summarize the efficacy of postabortion uterine artery embolization in cases of refractory hemorrhage. METHODS: Forty-two women were identified who had postabortion uterine artery embolization at San Francisco General Hospital between January 2000 and August 2007. Seven underwent embolization for hemorrhage caused by abnormal placentation. RESULTS: Embolization was successful in 90% (38 of 42) of cases. All failures (n=4) were in patients who had confirmed abnormal placentation. However, three of seven women (43%) with probable accreta diagnosed by ultrasonography were treated successfully with uterine artery embolization. Two patients experienced complications of uterine artery embolization. These complications—one contrast reaction and one femoral artery embolus—were treated without further sequelae. CONCLUSION: Uterine artery embolization is an alternative to hysterectomy in patients with postabortion hemorrhage refractory to conservative measures, especially when hemorrhage is caused by uterine atony or cervical laceration. LEVEL OF EVIDENCE: III
Early Human Development | 2002
Alan Leviton; Lewis B. Holmes; Elizabeth N. Allred; Juan Vargas
In this methodological paper, we explore a number of issues that pose problems for those who seek the antecedents of congenital microcephaly. We pay particular attention to three concerns: Who is a case? How should cases be classified? To whom should cases be compared?
American Journal of Obstetrics and Gynecology | 2013
Jin-Yi Kuk; Jung-Ju An; H.-S. Cha; Suk-Joo Choi; Juan Vargas; Soo-young Oh; Cheong-Rae Roh; Jong-Hwa Kim
OBJECTIVE The objective of the study was to investigate the effect of a single course of antenatal corticosteroid (ACS) therapy on the incidence of respiratory distress syndrome (RDS) in preterm twins according to the time interval between ACS administration and delivery. STUDY DESIGN We performed a retrospective cohort study of twins born between 24 and 34 weeks of gestation from November 1995 to May 2011. Subjects were grouped on the basis of the time interval between the first ACS dose and delivery: the ACS-to-delivery interval of less than 2 days (n = 166), 2-7 days (n = 114), and more than 7 days (n = 66). Pregnancy and neonatal outcomes of each group were compared with a control group of twins who were not exposed to ACS (n = 122). Multiple logistic regression analysis was used to examine the association between the ACS-to-delivery interval and the incidence of RDS after adjusting for potential confounding variables. RESULTS Compared with the ACS nonexposure group, the incidence of RDS in the group with an ACS-to-delivery interval of less than 2 days was not significantly different (adjusted odds ratio [aOR], 1.089; 95% confidence interval [CI], 0.524-2.262; P = .819). RDS occurred significantly less frequently when the ACS-to-delivery interval was between 2 and 7 days (aOR, 0.419; 95% CI, 0.181-0.968; P = .042). However, there was no significant reduction in the incidence of RDS when the ACS-to-delivery interval exceeded 7 days (aOR, 2.205; 95% CI, 0.773-6.292; P = .139). CONCLUSION In twin pregnancies, a single course of ACS treatment was associated with a decreased rate of RDS only when the ACS-to-delivery interval was between 2 and 7 days.
Clinical Obstetrics and Gynecology | 2009
Juan Vargas; Justin T. Diedrich
Second-trimester abortions are most commonly performed in the United States via dilation and evacuation; however, there are instances in which the use of systemic abortifacients is necessary. Lack of trained staff to perform late abortion procedures, fetal anomalies, and patient preference are important considerations when selecting the method of termination. Second-trimester abortions with misoprostol-only protocols require higher doses, side effects are more common, and the time to complete the abortion is longer in comparison to mifepristone-misoprostol combinations. Feticidal agents are recommended to avoid transient fetal survival. This chapter will review medical induction methods between gestational ages of 14 and 24 weeks that are commonly used in the United States.
American Journal of Obstetrics and Gynecology | 1999
Juan Vargas; S. Harvey Mudd; Susan E. Waisbren; Harvey L. Levy
gamma-Cystathionase deficiency (cystathioninemia-cystathioninuria) is a disorder of the transsulfuration pathway characterized by the accumulation of cystathionine in blood and urine. There are probably no clinical consequences. However, maternal gamma-cystathionase deficiency has not been reported. We studied 2 pregnancies and the offspring of these pregnancies in a woman with the pyridoxine-nonresponsive form of the disorder. The outcomes were favorable, suggesting that maternal gamma-cystathionase deficiency may not be deleterious to the pregnant woman or the fetus.
Journal of Perinatology | 2016
B E O'Donnell; Adam K. Lewkowitz; Juan Vargas; Marya G. Zlatnik
Objective:The objective of this study is to evaluate the informative content of two free, pregnancy-specific smartphone applications and their accuracy and adherence to prenatal care guidelines.Study Design:This is a qualitative analysis of the information delivered through two free, pregnancy-specific smartphone applications (apps): Text4Baby (T4B) and Baby Center’s ‘My Pregnancy Today’ (BC). All information from conception through 2 weeks postpartum were transcribed and coded independently by two physician researchers. Content was analyzed and assigned thematic codes. The proportion of content each app delivered per theme was then calculated and the χ2-test was used to compare thematic frequency between apps.Results:A total of 609 pieces of daily content were transcribed; 698 message themes were coded and analyzed. Most information delivered by T4B was about fetal development (23.8%) or prenatal care (16.6%); most content from BC was about normal pregnancy symptoms (20.1%) or maternal well-being (21.1%); the differences between apps for each of these themes were statistically significant (P<0.05). A total of four messages contained incomplete or ambiguous content; neither app delivered overtly incorrect medical information. T4B and BC had a similar proportion of information that was in-line with the American College of Obstetrics and Gynecology Guidelines for Prenatal Care. Neither app delivered any messages about contraception.Conclusion:T4B and BC are free, pregnancy-specific apps with different focuses. Neither app delivers comprehensive prenatal information, as evidenced by the absence of information about postpartum contraception. More information is needed to determine the role of such apps in prenatal care.