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Obstetrics & Gynecology | 2007

Antioxidant Therapy to Prevent Preeclampsia A Randomized Controlled Trial

Joseph A. Spinnato; Salvio Freire; João Luiz Pinto e Silva; Marilza Vieira Cunha Rudge; Sérgio Martins-Costa; Matthew A. Koch; Norman Goco; Cleide de Barros Santos; José Guilherme Cecatti; Roberto Antonio de Araújo Costa; José Geraldo Lopes Ramos; Nancy Moss; Baha M. Sibai

OBJECTIVE: To study whether antioxidant supplementation will reduce the incidence of preeclampsia among patients at increased risk. METHODS: A randomized, placebo-controlled, double-blind clinical trial was conducted at four Brazilian sites. Women between 12 0/7 weeks and 19 6/7 weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomly assigned to daily treatment with both vitamin C (1,000 mg) and vitamin E (400 International Units) or placebo. Analyses were adjusted for clinical site and risk group (prior preeclampsia, chronic hypertension, or both). A sample size of 734 would provide 80% power to detect a 40% reduction in the risk of preeclampsia, assuming a placebo group rate of 21% and &agr;=.05. The &agr; level for the final analysis, adjusted for interim looks, was 0.0458. RESULTS: Outcome data for 707 of 739 randomly assigned patients revealed no significant reduction in the rate of preeclampsia (study drug, 13.8% [49 of 355] compared with placebo, 15.6% [55 of 352], adjusted risk ratio 0.87 [95.42% confidence interval 0.61–1.25]). There were no differences in mean gestational age at delivery or rates of perinatal mortality, abruptio placentae, preterm delivery, and small for gestational age or low birth weight infants. Among patients without chronic hypertension, there was a slightly higher rate of severe preeclampsia in the study group (study drug, 6.5% [11 of 170] compared with placebo, 2.4% [4 of 168], exact P=.11, odds ratio 2.78, 95% confidence interval 0.79–12.62). CONCLUSION: This trial failed to demonstrate a benefit of antioxidant supplementation in reducing the rate of preeclampsia among patients with chronic hypertension and/or prior preeclampsia. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.ClinicalTrials.gov, NCT00097110 LEVEL OF EVIDENCE: I


Nutrition and Cancer | 2004

Clinical characteristics and pharmacokinetics of purified soy isoflavones: Multiple-dose administration to men with prostate neoplasia

Leslie M. Fischer; Chrysa Mahoney; A. Robert Jeffcoat; Matthew A. Koch; Brian F. Thomas; John L. Valentine; Thomas Stinchcombe; Jarol Boan; James A. Crowell; Steven H. Zeisel

A phase I clinical trial was conducted to determine the safety, pharmacokinetic parameters, and efficacy of orally administered isoflavones (genistein and daidzein, potential cancer chemotherapeutic agents) over a 3-mo period in men with prostate neoplasia. Twenty men, ages 40 and above, with stage B, C, or D adenocarcinoma of the prostate were treated with a multiple-dose regimen of a soy isoflavone formulation (delivering approximately 300 or 600 mg/day genistein and half this much daidzein) for 84 days. The delivered dose of isoflavones was more than 10-fold higher than that typically taken by prostate cancer patients. In men with prostate cancer, relatively minor side effects of chronic isoflavone treatment were observed including some estrogenic effects (breast changes, increased frequency of hot flashes). Serum dehydroepiandrosterone was decreased by 31.7% (P = 0.0004) at the end of treatment. Except for those subjects whose prostate-specific antigen (PSA) values were below 0.4 ng/ml, subjects had a history of increasing PSA levels prior to the trial. This increase continued during the trial both while on soy isoflavones and after treatment was discontinued. On average the rate of rise accelerated after soy isoflavones were discontinued, but that difference did not attain statistical significance. Genistein and daidzein were rapidly cleared from plasma and excreted in urine. Pharmacokinetic data for chronic dose administration were similar to single-dose administration for the isoflavones investigated except that we observed slightly longer circulation time for daidzein.


Obstetrics & Gynecology | 1996

A randomized controlled trial of smoking cessation intervention in pregnancy in an academic clinic

Katherine E Hartmann; John M. Thorp; Laurie Pahel-Short; Matthew A. Koch

To evaluate the effectiveness of a physician-based intervention to promote smoking cessation during pregnancy, we conducted this randomized controlled trial in the resident-staffed prenatal clinics at the University of North Carolina Womens Hospital . Two hundred fifty prenatal patients who smoked were enrolled at their first visit and randomly assigned to the intervention or the usual-care group. Resident physicians provided self-help materials to intervention subjects and used a script to set goals with them at each prenatal visit. Subjects who set quit dates were contacted by volunteer cessation counselors. To verify smoking status, subjects provided a self-report and breath carbon monoxide (CO) sample at each visit. Controls were similarly assessed at enrollment and at three additional predetermined intervals. Twenty percent of intervention subjects and 10% of controls reported cessation, which was verified by CO level (P = .052). Fifty-one percent of subjects reduced their consumption by half or more, compared with 30% of controls (P = .002). The intervention is effective in promoting smoking cessation and reduction. In addition, this technique is inexpensive, readily accepted by staff, and efficient.


Obstetrics & Gynecology | 2010

A new system for determining the causes of stillbirth.

Donald J. Dudley; Robert L. Goldenberg; Deborah L. Conway; Robert M. Silver; George R. Saade; Michael W. Varner; Halit Pinar; Donald R. Coustan; Radek Bukowski; Barbara J. Stoll; Matthew A. Koch; Corette B. Parker; Uma M. Reddy

OBJECTIVE: To describe the methods for assigning the cause of death for stillbirths enrolled in the Stillbirth Collaborative Research Network (SCRN). METHODS: A complete evaluation, including postmortem examination, placental pathology, medical record abstraction, and maternal interview was available on 512 stillbirths among 500 women. These 512 stillbirths were evaluated for cause of death using the definitions outlined in this report. Using the best available evidence, SCRN investigators developed a new methodology to assign the cause of death of stillbirths using clinical, postmortem, and placental pathology data. This new tool, designated the Initial Causes of Fetal Death, incorporates known causes of death and assigns them as possible or probable based on strict diagnostic criteria, derived from published references and pathophysiologic sequences that lead to stillbirth. RESULTS: Six broad categories of causes of death are accounted for, including maternal medical conditions; obstetric complications; maternal or fetal hematologic conditions; fetal genetic, structural, and karyotypic abnormalities; placental infection, fetal infection, or both; and placental pathologic findings. Isolated histologic chorioamnionitis and small for gestational age were not considered causes of death. CONCLUSION: A new system, Initial Causes of Fetal Death, to assign cause of death in stillbirths was developed by the SCRN investigators for use in this study but has broader applicability. Initial Causes of Fetal Death is a standardized method to assign probable and possible causes of death of stillbirths based on information routinely collected during prenatal care and the clinical evaluation of fetal death.


Obstetrics & Gynecology | 2014

Placental findings in singleton stillbirths

Halit Pinar; Robert L. Goldenberg; Matthew A. Koch; Josefine Heim-Hall; Hal K. Hawkins; Bahig M. Shehata; Carlos R. Abramowsky; Corette B. Parker; Donald J. Dudley; Robert M. Silver; Barbara J. Stoll; Marshall Carpenter; George R. Saade; Janet Moore; Deborah L. Conway; Michael W. Varner; Carol J. Hogue; Donald R. Coustan; Elena Sbrana; Vanessa Thorsten; Marian Willinger; Uma M. Reddy

OBJECTIVE: To compare placental lesions for stillbirth cases and live birth controls in a population-based study. METHODS: Pathologic examinations were performed on placentas from singleton pregnancies using a standard protocol. Data were analyzed overall and within gestational age groups at delivery. RESULTS: Placentas from 518 stillbirths and 1,200 live births were studied. Single umbilical artery was present in 7.7% of stillbirths and 1.7% of live births, velamentous cord insertion was present in 5% of stillbirths and 1.1% of live births, diffuse terminal villous immaturity was present in 10.3% of stillbirths and 2.3% of live births, inflammation (eg, acute chorioamnionitis of placental membranes) was present in 30.4% of stillbirths and 12% of live births, vascular degenerative changes in chorionic plate were present in 55.7% of stillbirths and 0.5% of live births, retroplacental hematoma was present in 23.8% of stillbirths and 4.2% of live births, intraparenchymal thrombi was present in 19.7% of stillbirths and 13.3% of live births, parenchymal infarction was present in 10.9% of stillbirths and 4.4% of live births, fibrin deposition was present in 9.2% of stillbirths and 1.5% of live births, fetal vascular thrombi was present in 23% of stillbirths and 7% of live births, avascular villi was present in 7.6% of stillbirths and 2.0% of live births, and hydrops was present in 6.4% of stillbirths and 1.0% of live births. Among stillbirths, inflammation and retroplacental hematoma were more common in placentas from early deliveries, whereas thrombotic lesions were more common in later gestation. Inflammatory lesions were especially common in early live births. CONCLUSIONS: Placental lesions were highly associated with stillbirth compared with live births. All lesions associated with stillbirth were found in live births but often with variations by gestational age at delivery. Knowledge of lesion prevalence within gestational age groups in both stillbirths and live birth controls contributes to an understanding of the association between placental abnormality and stillbirth. LEVEL OF EVIDENCE: II


Archive | 2010

Zidovudine in Asymptomatic Human Immunodeficiency Virus Infection

Paul A. Volberding; Stephen W. Lagakos; Matthew A. Koch; Carla Pettinelli; Maureen W. Myers; David K. Booth; Henry H. Balfour; Richard C. Reichman; John A. Bartlett; Martin S. Hirsch; Robert L. Murphy; W. David Hardy; Ruy Soeiro; Margaret A. Fischl; John G. Bartlett; Thomas C. Merigan; Newton E. Hyslop; Douglas D. Richman; Fred T. Valentine; Lawrence Corey

Zidovudine (AZT) is a potent inhibitor of the replication of the human immunodeficiency virus (HIV), and it has been shown to improve survival in advanced HIV disease. We conducted a randomized, double-blind trial in adults with asymptomatic HIV infection who had CD4+ cell counts of fewer than 500 per cubic millimeter on entry into the study. The subjects (92 percent male) were randomly assigned to one of three treatment groups: placebo (428 subjects); zidovudine, 500 mg per day (453); or zidovudine, 1500 mg per day (457). After a mean follow-up of 55 weeks (range, 19 to 107), 33 of the subjects assigned to placebo had the acquired immunodeficiency syndrome (AIDS), as compared with 11 of those assigned to receive 500 mg of zidovudine (P = 0.002; relative risk, 2.8; 95 percent confidence interval, 1.4 to 5.6) and 14 of those assigned to receive 1500 mg of zidovudine (P = 0.05; relative risk, 1.9; 95 percent confidence interval, 1.0 to 3.5). In the three treatment groups, the rates of progression (per 100 person-years) to either AIDS or advanced AIDS-related complex were 7.6, 3.6, and 4.3, respectively. As compared with those assigned to placebo, the subjects in the zidovudine groups had significant increases in the number of CD4+ cells and significant declines in p24 antigen levels. In the 1500-mg zidovudine group, severe hematologic toxicity (anemia or neutropenia) was more frequent than in the other groups (P less than 0.0001). In the 500-mg zidovudine group, nausea was the only toxicity that was significantly more frequent (in 3.3 percent) than in the placebo group (P = 0.001). We conclude that zidovudine is safe and effective in persons with asymptomatic HIV infection and fewer than 500 CD4+ cells per cubic millimeter. Additional study will be required to determine whether such treatment will ultimately improve survival for persons infected with HIV.


Obstetrics & Gynecology | 2014

Association between stillbirth and illicit drug use and smoking during pregnancy

Michael W. Varner; Robert M. Silver; Carol J. Hogue; Marian Willinger; Corette B. Parker; Vanessa Thorsten; Robert L. Goldenberg; George R. Saade; Donald J. Dudley; Donald R. Coustan; Barbara J. Stoll; Radek Bukowski; Matthew A. Koch; Deborah L. Conway; Halit Pinar; Uma M. Reddy

OBJECTIVE: To compare illicit drug and smoking use in pregnancies with and without stillbirth. METHODS: The Stillbirth Collaborative Research Network conducted a case–control study from March 2006 to September 2008, covering more than 90% of deliveries to residents of five a priori–defined geographically diverse regions. The study attempted to include all stillbirths and representative liveborn controls. Umbilical cord samples from cases and controls were collected and frozen for subsequent batch analysis. Maternal serum was collected at delivery and batch analyzed for cotinine. RESULTS: For 663 stillbirth deliveries, 418 (63%) had cord homogenate and 579 (87%) had maternal cotinine assays performed. For 1,932 live birth deliveries, 1,050 (54%) had cord homogenate toxicology and 1,545 (80%) had maternal cotinine assays performed. A positive cord homogenate test for any illicit drug was associated with stillbirth (odds ratio [OR] 1.94, 95% confidence interval [CI] 1.16–3.27). The most common individual drug was cannabis (OR 2.34 95% CI 1.13–4.81), although the effect was partially confounded by smoking. Both maternal self-reported smoking history and maternal serum cotinine levels were associated in a dose–response relationship with stillbirth. Positive serum cotinine less than 3 ng/mL and no reported history of smoking (proxy for passive smoke exposure) also were associated with stillbirth (OR 2.06, 95% CI 1.24–3.41). CONCLUSION: Cannabis use, smoking, illicit drug use, and apparent exposure to second-hand smoke, separately or in combination, during pregnancy were associated with an increased risk of stillbirth. Because cannabis use may be increasing with increased legalization, the relevance of these findings may increase as well. LEVEL OF EVIDENCE: II


American Journal of Obstetrics and Gynecology | 2008

Serum inhibin A and angiogenic factor levels in pregnancies with previous preeclampsia and/or chronic hypertension: are they useful markers for prediction of subsequent preeclampsia?

Baha M. Sibai; Matthew A. Koch; Salvio Freire; João Luiz Pinto e Silva; Marilza Vieira Cunha Rudge; Sérgio Martins-Costa; Janet Bartz; Cleide de Barros Santos; José Guilherme Cecatti; Roberto Antonio de Araújo Costa; José Geraldo Lopes Ramos; Joseph A. Spinnato

OBJECTIVE Our objective was to determine whether measurement of placenta growth factor (PLGF), inhibin A, or soluble fms-like tyrosine kinase-1 (sFlt-1) at 2 times during pregnancy would usefully predict subsequent preeclampsia (PE) in women at high risk. STUDY DESIGN We analyzed serum obtained at enrollment (12(0/7) to 19(6/7) weeks) and follow-up (24-28 weeks) from 704 patients with previous PE and/or chronic hypertension (CHTN) enrolled in a randomized trial for the prevention of PE. Logistic regression analysis assessed the association of log-transformed markers with subsequent PE; receiver operating characteristic analysis assessed predictive value. RESULTS One hundred four developed preeclampsia: 27 at 37 weeks or longer and 77 at less than 37 weeks (9 at less than 27 weeks). None of the markers was associated with PE at 37 weeks or longer. Significant associations were observed between PE at less than 37 weeks and reduced PLGF levels at baseline (P = .022) and follow-up (P < .0001) and elevated inhibin A (P < .0001) and sFlt-1 (P = .0002) levels at follow-up; at 75% specificity, sensitivities ranged from 38% to 52%. Using changes in markers from baseline to follow-up, sensitivities were 52-55%. Associations were observed between baseline markers and PE less than 27 weeks (P < or = .0004 for all); sensitivities were 67-89%, but positive predictive values (PPVs) were only 3.4-4.5%. CONCLUSION Inhibin A and circulating angiogenic factors levels obtained at 12(0/7) to 19(6/7) weeks have significant associations with onset of PE at less than 27 weeks, as do levels obtained at 24-28 weeks with onset of PE at less than 37 weeks. However, because the corresponding sensitivities and/or PPVs were low, these markers might not be clinically useful to predict PE in women with previous PE and/or CHTN.


American Journal of Obstetrics and Gynecology | 2008

Antioxidant Supplementation and Premature Rupture of the Membranes: A Planned Secondary Analysis

Joseph A. Spinnato; Salvio Freire; João Luiz Pinto e Silva; Marilza Vieira Cunha Rudge; Sérgio Martins-Costa; Matthew A. Koch; Norman Goco; Cleide de Barros Santos; José Guilherme Cecatti; Roberto Antonio de Araújo Costa; José Geraldo Lopes Ramos; Nancy Moss; Baha M. Sibai

OBJECTIVE The purpose of this study was to determine if antioxidant supplementation during pregnancy reduces the incidence of premature rupture of the membranes (PROM). STUDY DESIGN A placebo-controlled, double-blind trial was conducted. PROM and preterm PROM (PPROM) were planned secondary outcomes of the trial. Women between 12(0/7) and 19(6/7) weeks of gestation and diagnosed to have chronic hypertension or a prior history of preeclampsia were randomized to daily treatment with both vitamin C (1000 mg) and E (400 IU) or placebo. RESULTS Outcome data for PROM were available for 697 of 739 patients. The rates of PROM (37/349 [10.6%] vs 19/348 [5.5%]; adjusted risk ratio [RR] 1.89 [95.42% CI, 1.11-3.23]; P = .015), and PPROM (16/349 [4.6%] vs 6/348 [1.7%]; RR 2.68 [1.07-6.71]; P = .025) were increased in the antioxidant group. CONCLUSION Contrary to expectations, vitamins C and E supplementation in this dose combination may be associated with an increased risk of PROM and PPROM.


Malaria Journal | 2011

Population pharmacokinetics of artesunate and dihydroartemisinin in pregnant and non-pregnant women with malaria

Carrie A. Morris; Marie Onyamboko; Edmund V. Capparelli; Matthew A. Koch; Joseph Atibu; Vicky Lokomba; Macaya Douoguih; Jennifer Hemingway-Foday; David Wesche; Robert W. Ryder; Carl Bose; Linda L. Wright; Antoinette Tshefu; Steven R. Meshnick; Lawrence Fleckenstein

BackgroundThe World Health Organization endorses the use of artemisinin-based combination therapy for treatment of acute uncomplicated falciparum malaria in the second and third trimesters of pregnancy. However, the effects of pregnancy on the pharmacokinetics of artemisinin derivatives, such as artesunate (AS), are poorly understood. In this analysis, the population pharmacokinetics of oral AS, and its active metabolite dihydroartemisinin (DHA), were studied in pregnant and non-pregnant women at the Kingasani Maternity Clinic in the DRC.MethodsData were obtained from 26 pregnant women in the second (22 - 26 weeks) or the third (32 - 36 weeks) trimester of pregnancy and from 25 non-pregnant female controls. All subjects received 200 mg AS. Plasma AS and DHA were measured using a validated LC-MS method. Estimates for pharmacokinetic and variability parameters were obtained through nonlinear mixed effects modelling.ResultsA simultaneous parent-metabolite model was developed consisting of mixed zero-order, lagged first-order absorption of AS, a one-compartment model for AS, and a one-compartment model for DHA. Complete conversion of AS to DHA was assumed. The model displayed satisfactory goodness-of-fit, stability, and predictive ability. Apparent clearance (CL/F) and volume of distribution (V/F) estimates, with 95% bootstrap confidence intervals, were as follows: 195 L (139-285 L) for AS V/F, 895 L/h (788-1045 L/h) for AS CL/F, 91.4 L (78.5-109 L) for DHA V/F, and 64.0 L/h (55.1-75.2 L/h) for DHA CL/F. The effect of pregnancy on DHA CL/F was determined to be significant, with a pregnancy-associated increase in DHA CL/F of 42.3% (19.7 - 72.3%).ConclusionsIn this analysis, pharmacokinetic modelling suggests that pregnant women have accelerated DHA clearance compared to non-pregnant women receiving orally administered AS. These findings, in conjunction with a previous non-compartmental analysis of the modelled data, provide further evidence that higher AS doses would be required to maintain similar DHA levels in pregnant women as achieved in non-pregnant controls.

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Marian Willinger

National Institutes of Health

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Barbara J. Stoll

University of Texas Health Science Center at Houston

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Donald J. Dudley

University of Texas Health Science Center at San Antonio

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