Reference ranges for Doppler indices of umbilical and fetal middle cerebral arteries and cerebroplacental ratio: systematic review.

OBJECTIVE: To assess studies reporting reference ranges for umbilical artery (UA) and fetal middle cerebral artery (MCA) Doppler indices and cerebroplacental ratio (CPR), using a set of predefined methodological quality criteria for study design, statistical analysis and reporting methods. METHODS: This was a systematic review of observational studies in which the primary aim was to create reference ranges for UA and MCA Doppler indices and CPR in fetuses of singleton gestations. A search for relevant articles was performed in MEDLINE, EMBASE, CINAHL, Web of Science (from inception to 31 December 2016) and references of the retrieved articles. Two authors independently selected studies, assessed the risk of bias and extracted the data. Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was assigned to each study. Linear multiple regression analysis assessing the association between quality scores and study characteristics was performed. RESULTS: Thirty-eight studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'ultrasound quality control measures', in which only two studies demonstrated a comprehensive quality-control strategy; 'number of measurements taken for each Doppler variable', which was apparent in only three studies; 'sonographer experience', in which no study on CPR reported clearly the experience or training of the sonographers, while only three studies on UA Doppler and four on MCA Doppler did; and 'blinding of measurements', in which only one study, on UA Doppler, reported that sonographers were blinded to the measurement recorded during the examination. Sample size estimations were present in only seven studies. No predictors of quality were found on multiple regression analysis. Reference ranges varied significantly with important clinical implications for what is considered normal or abnormal, even when restricting the analysis to the highest scoring studies. CONCLUSIONS: There is considerable methodological heterogeneity in studies reporting reference ranges for UA and MCA Doppler indices and CPR, and the resulting references have important implications for clinical practice. There is a need for the standardization of methodologies for Doppler velocimetry and for the development of reference standards, which can be correctly interpreted and applied in clinical practice. We propose a set of recommendations for this purpose. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Intervalos de referencia para los índices Doppler de la arterias umbilical y cerebral media del feto y la relación cerebroplacentaria: una revisión sistemática OBJETIVO: Evaluar los estudios que informan sobre intervalos de referencia para los índices Doppler y la relación cerebroplacentaria (RCP) de la arteria umbilical (AU) y la arteria cerebral media (ACM) del feto, mediante un conjunto de criterios de calidad metodológica predefinidos para el diseño del estudio, el análisis estadístico y los métodos de notificación. MÉTODOS: Esta fue una revisión sistemática de estudios observacionales en los que el objetivo principal fue crear intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP de fetos de gestaciones con feto único. Se realizó una búsqueda de artículos relevantes en MEDLINE, EMBASE, CINAHL, Web of Science (desde el inicio hasta el 31 de diciembre de 2016) y en las referencias de los artículos recuperados. Dos autores, de forma independiente, seleccionaron los estudios, evaluaron el riesgo de sesgo y extrajeron los datos. Los estudios se calificaron según un conjunto predefinido de criterios metodológicos acordados de forma independiente y se asignó una puntuación de calidad global a cada estudio. Se realizó un análisis de regresión múltiple lineal para evaluar la asociación entre las puntuaciones de calidad y las características del estudio. RESULTADOS: Un total de 38 estudios cumplieron los criterios de inclusión. El mayor potencial de sesgo se observó en los siguientes casos: 'medidas de control de calidad del ultrasonido', donde sólo dos estudios demostraron una estrategia integral de control de calidad; 'número de mediciones tomadas para cada variable Doppler', que solo fue aparente en tres estudios; 'experiencia del ecografista', puesto que ningún estudio sobre la RCP informó claramente sobre la experiencia o la formación de los ecografistas, y tan solo lo hicieron tres estudios sobre el Doppler de la AU y cuatro sobre el Doppler de la ACM; y 'mediciones a ciegas', donde tan sólo un estudio sobre el Doppler de la AU comunicó que los ecografistas no tuvieron acceso a la medición registrada durante el estudio. Las estimaciones del tamaño de la muestra sólo se comunicaron en siete estudios. No se encontraron predictores de calidad en el análisis de regresión múltiple. Los intervalos de referencia variaron significativamente con implicaciones clínicas importantes para lo que se considera normal o anómalo, incluso cuando se restringió el análisis a los estudios con mayor puntuación. CONCLUSIONES: Existe una heterogeneidad metodológica considerable en los estudios que informan sobre los intervalos de referencia para los índices Doppler de la AU y la ACM y la RCP, y las referencias resultantes tienen implicaciones importantes para la práctica clínica. Es necesario estandarizar las metodologías de la velocimetría Doppler y desarrollar estándares de referencia que puedan ser interpretados y aplicados correctamente en la práctica clínica. Se propone una serie de recomendaciones para este fin.

Predictive accuracy of cerebroplacental ratio for adverse perinatal and neurodevelopmental outcomes in suspected fetal growth restriction: systematic review and meta-analysis.

OBJECTIVE: The cerebroplacental ratio (CPR) has been proposed for the routine surveillance of pregnancies with suspected fetal growth restriction (FGR), but the predictive performance of this test is unclear. The aim of this study was to determine the accuracy of CPR for predicting adverse perinatal and neurodevelopmental outcomes in suspected FGR. METHODS: PubMed, EMBASE, CINAHL and Lilacs were searched from inception to 31 July 2017 for cohort or cross-sectional studies reporting on the accuracy of CPR for predicting adverse perinatal and/or neurodevelopmental outcomes in singleton pregnancies with FGR suspected antenatally based on sonographic parameters. Summary receiver-operating characteristics (ROC) curves, pooled sensitivities and specificities, and summary likelihood ratios (LRs) were generated. RESULTS: Twenty-two studies (including 4301 women) met the inclusion criteria. Summary ROC curves showed that the best predictive accuracy of CPR was for perinatal death and the worst was for neonatal acidosis, with areas under the summary ROC curves of 0.83 and 0.57, respectively. The predictive accuracy of CPR was moderate to high for perinatal death (pooled sensitivity and specificity of 93% and 76%, respectively, and summary positive and negative LRs of 3.9 and 0.09, respectively) and low for composite of adverse perinatal outcomes, Cesarean section for non-reassuring fetal status, 5-min Apgar score < 7, admission to the neonatal intensive care unit, neonatal acidosis and neonatal morbidity, with summary positive and negative LRs ranging from 1.1 to 2.5 and 0.3 to 0.9, respectively. An abnormal CPR result had moderate accuracy for predicting small-for-gestational age at birth (summary positive LR of 7.4). CPR had a higher predictive accuracy in pregnancies with suspected early-onset FGR. No study provided data for assessing the predictive accuracy of CPR for adverse neurodevelopmental outcome. CONCLUSION: CPR appears to be useful in predicting perinatal death in pregnancies with suspected FGR. Nevertheless, before incorporating CPR into the routine clinical management of suspected FGR, randomized controlled trials should assess whether the use of CPR reduces perinatal death or other adverse perinatal outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Vaginal progesterone decreases preterm birth and neonatal morbidity and mortality in women with a twin gestation and a short cervix: an updated meta-analysis of individual patient data.

OBJECTIVE: To assess the efficacy of vaginal progesterone for the prevention of preterm birth and neonatal morbidity and mortality in asymptomatic women with a twin gestation and a sonographic short cervix (cervical length ≤ 25 mm) in the mid-trimester. METHODS: This was an updated systematic review and meta-analysis of individual patient data (IPD) from randomized controlled trials comparing vaginal progesterone with placebo/no treatment in women with a twin gestation and a mid-trimester sonographic cervical length ≤ 25 mm. MEDLINE, EMBASE, POPLINE, CINAHL and LILACS (all from inception to 31 December 2016), the Cochrane Central Register of Controlled Trials, Research Registers of ongoing trials, Google Scholar, conference proceedings and reference lists of identified studies were searched. The primary outcome measure was preterm birth < 33 weeks' gestation. Two reviewers independently selected studies, assessed the risk of bias and extracted the data. Pooled relative risks (RRs) with 95% confidence intervals (CI) were calculated. RESULTS: IPD were available for 303 women (159 assigned to vaginal progesterone and 144 assigned to placebo/no treatment) and their 606 fetuses/infants from six randomized controlled trials. One study, which included women with a cervical length between 20 and 25 mm, provided 74% of the total sample size of the IPD meta-analysis. Vaginal progesterone, compared with placebo/no treatment, was associated with a statistically significant reduction in the risk of preterm birth < 33 weeks' gestation (31.4% vs 43.1%; RR, 0.69 (95% CI, 0.51-0.93); moderate-quality evidence). Moreover, vaginal progesterone administration was associated with a significant decrease in the risk of preterm birth < 35, < 34, < 32 and < 30 weeks' gestation (RRs ranging from 0.47 to 0.83), neonatal death (RR, 0.53 (95% CI, 0.35-0.81)), respiratory distress syndrome (RR, 0.70 (95% CI, 0.56-0.89)), composite neonatal morbidity and mortality (RR, 0.61 (95% CI, 0.34-0.98)), use of mechanical ventilation (RR, 0.54 (95% CI, 0.36-0.81)) and birth weight < 1500 g (RR, 0.53 (95% CI, 0.35-0.80)) (all moderate-quality evidence). There were no significant differences in neurodevelopmental outcomes at 4-5 years of age between the vaginal progesterone and placebo groups. CONCLUSION: Administration of vaginal progesterone to asymptomatic women with a twin gestation and a sonographic short cervix in the mid-trimester reduces the risk of preterm birth occurring at < 30 to < 35 gestational weeks, neonatal mortality and some measures of neonatal morbidity, without any demonstrable deleterious effects on childhood neurodevelopment. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Vaginal progesterone decreases preterm birth ≤ 34 weeks of gestation in women with a singleton pregnancy and a short cervix: an updated meta-analysis including data from the OPPTIMUM study.

OBJECTIVE: To evaluate the efficacy of vaginal progesterone administration for preventing preterm birth and perinatal morbidity and mortality in asymptomatic women with a singleton gestation and a mid-trimester sonographic cervical length (CL) ≤ 25 mm. METHODS: This was an updated systematic review and meta-analysis of randomized controlled trials comparing the use of vaginal progesterone to placebo/no treatment in women with a singleton gestation and a mid-trimester sonographic CL ≤ 25 mm. Electronic databases, from their inception to May 2016, bibliographies and conference proceedings were searched. The primary outcome measure was preterm birth ≤ 34 weeks of gestation or fetal death. Two reviewers independently selected studies, assessed the risk of bias and extracted the data. Pooled relative risks (RRs) with 95% confidence intervals (CI) were calculated. RESULTS: Five trials involving 974 women were included. A meta-analysis, including data from the OPPTIMUM study, showed that vaginal progesterone significantly decreased the risk of preterm birth ≤ 34 weeks of gestation or fetal death compared to placebo (18.1% vs 27.5%; RR, 0.66 (95% CI, 0.52-0.83); P = 0.0005; five studies; 974 women). Meta-analyses of data from four trials (723 women) showed that vaginal progesterone administration was associated with a statistically significant reduction in the risk of preterm birth occurring at < 28 to < 36 gestational weeks (RRs from 0.51 to 0.79), respiratory distress syndrome (RR, 0.47 (95% CI, 0.27-0.81)), composite neonatal morbidity and mortality (RR, 0.59 (95% CI, 0.38-0.91)), birth weight < 1500 g (RR, 0.52 (95% CI, 0.34-0.81)) and admission to the neonatal intensive care unit (RR, 0.67 (95% CI, 0.50-0.91)). There were no significant differences in neurodevelopmental outcomes at 2 years of age between the vaginal progesterone and placebo groups. CONCLUSION: This updated systematic review and meta-analysis reaffirms that vaginal progesterone reduces the risk of preterm birth and neonatal morbidity and mortality in women with a singleton gestation and a mid-trimester CL ≤ 25 mm, without any deleterious effects on neurodevelopmental outcome. Clinicians should continue to perform universal transvaginal CL screening at 18-24 weeks of gestation in women with a singleton gestation and to offer vaginal progesterone to those with a CL ≤ 25 mm. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

First- and second-trimester tests to predict stillbirth in unselected pregnant women: a systematic review and meta-analysis.

BACKGROUND: Several biophysical and biochemical tests have been proposed to predict stillbirth but their predictive ability remains unclear. OBJECTIVE: To assess the accuracy of tests performed during the first and/or second trimester of pregnancy to predict stillbirth in unselected women with singleton, structurally and chromosomally normal fetuses through use of formal methods for systematic reviews and meta-analytic techniques. SEARCH STRATEGY: Electronic databases, bibliographies and conference proceedings. SELECTION CRITERIA: Observational studies that evaluated the predictive accuracy for stillbirth of tests performed during the first two trimesters of pregnancy. DATA COLLECTION AND ANALYSIS: Two reviewers selected studies, assessed risk of bias and extracted data. Summary receiver operating characteristic curves, pooled sensitivities, specificities and likelihood ratios (LRs) were generated. Data were synthesised separately for stillbirth as a sole category and for specific stillbirth categories. MAIN RESULTS: Seventy-one studies, evaluating 16 single and five combined tests, met the inclusion criteria. A uterine artery pulsatility index >90th centile during the second trimester and low levels of pregnancy-associated plasma protein A (PAPP-A) during the first trimester had a moderate to high predictive accuracy for stillbirth related to placental abruption, small-for-gestational-age or pre-eclampsia (positive and negative LRs from 6.3 to 14.1, and from 0.1 to 0.4, respectively). All biophysical and biochemical tests assessed had a low predictive accuracy for stillbirth as a sole category. CONCLUSIONS: Currently, there is no clinically useful first-trimester or second-trimester test to predict stillbirth as a sole category. Uterine artery pulsatility index and maternal serum PAPP-A levels appeared to be good predictors of stillbirth related to placental dysfunction disorders.

Pregnancy dating by fetal crown-rump length: a systematic review of charts.

BACKGROUND: Fetal crown-rump length (CRL) measurement by ultrasound in the first trimester is the standard method for pregnancy dating; however, a multitude of CRL equations to estimate gestational age (GA) are reported in the literature. OBJECTIVE: To evaluate the methodological quality used in studies reporting CRL equations to estimate GA using a set of predefined criteria. SEARCH STRATEGY: Searches of MEDLINE, EMBASE, and CINAHL databases, from 1948 to 31 January 2011, and secondary reference sources, were performed. SELECTION CRITERIA: Observational ultrasound studies, where the primary aim was to create equations for GA estimation using a CRL measurement. DATA COLLECTION AND ANALYSIS: Included studies were scored against predefined independently agreed methodological criteria: an overall quality score was calculated for each study. MAIN RESULTS: The searches yielded 1142 citations. Two reviewers screened the papers and independently assessed the full-text versions of 29 eligible studies. The highest potential for bias was noted in inclusion and exclusion criteria, and in maternal demographic characteristics. No studies had systematic ultrasound quality-control measures. The four studies with the highest scores (lowest risk of bias) satisfied 18 or more of the 29 criteria; these showed lower variation in GA estimation than the remaining, lower-scoring studies. This was particularly evident at the extremes of GA. AUTHOR'S CONCLUSIONS: Considerable methodological heterogeneity and limitations exist in studies reporting CRL equations for estimating GA, and these result in a wide range of estimated GAs for any given CRL; however, when studies with the highest methodological quality are used, this range is reduced.

Novel biomarkers for predicting intrauterine growth restriction: a systematic review and meta-analysis.

BACKGROUND: Several biomarkers for predicting intrauterine growth restriction (IUGR) have been proposed in recent years. However, the predictive performance of these biomarkers has not been systematically evaluated. OBJECTIVE: To determine the predictive accuracy of novel biomarkers for IUGR in women with singleton gestations. SEARCH STRATEGY: Electronic databases, reference list checking and conference proceedings. SELECTION CRITERIA: Observational studies that evaluated the accuracy of novel biomarkers proposed for predicting IUGR. DATA COLLECTION AND ANALYSIS: Data were extracted on characteristics, quality and predictive accuracy from each study to construct 2×2 tables. Summary receiver operating characteristic curves, sensitivities, specificities and likelihood ratios (LRs) were generated. MAIN RESULTS: A total of 53 studies, including 39,974 women and evaluating 37 novel biomarkers, fulfilled the inclusion criteria. Overall, the predictive accuracy of angiogenic factors for IUGR was minimal (median pooled positive and negative LRs of 1.7, range 1.0-19.8; and 0.8, range 0.0-1.0, respectively). Two small case-control studies reported high predictive values for placental growth factor and angiopoietin-2 only when IUGR was defined as birthweight centile with clinical or pathological evidence of fetal growth restriction. Biomarkers related to endothelial function/oxidative stress, placental protein/hormone, and others such as serum levels of vitamin D, urinary albumin:creatinine ratio, thyroid function tests and metabolomic profile had low predictive accuracy. CONCLUSIONS: None of the novel biomarkers evaluated in this review are sufficiently accurate to recommend their use as predictors of IUGR in routine clinical practice. However, the use of biomarkers in combination with biophysical parameters and maternal characteristics could be more useful and merits further research.

Systematic review of methodology used in ultrasound studies aimed at creating charts of fetal size.

BACKGROUND: Reliable ultrasound charts are necessary for the prenatal assessment of fetal size, yet there is a wide variation of methodologies for the creation of such charts. OBJECTIVE: To evaluate the methodological quality of studies of fetal biometry using a set of predefined quality criteria of study design, statistical analysis and reporting methods. SEARCH STRATEGY: Electronic searches in MEDLINE, EMBASE and CINAHL, and references of retrieved articles. SELECTION CRITERIA: Observational studies whose primary aim was to create ultrasound size charts for bi-parietal diameter, head circumference, abdominal circumference and femur length in fetuses from singleton pregnancies. DATA COLLECTION AND ANALYSIS: Studies were scored against a predefined set of independently agreed methodological criteria and an overall quality score was given to each study. Multiple regression analysis between quality scores and study characteristics was performed. MAIN RESULTS: Eighty-three studies met the inclusion criteria. The highest potential for bias was noted in the following fields: 'Inclusion/exclusion criteria', as none of the studies defined a rigorous set of antenatal or fetal conditions which should be excluded from analysis; 'Ultrasound quality control measures', as no study demonstrated a comprehensive quality assurance strategy; and 'Sample size calculation', which was apparent in six studies only. On multiple regression analysis, there was a positive correlation between quality scores and year of publication: quality has improved with time, yet considerable heterogeneity in study methodology is still observed today. CONCLUSIONS: There is considerable methodological heterogeneity in studies of fetal biometry. Standardisation of methodologies is necessary in order to make correct interpretations and comparisons between different charts. A checklist of recommended methodologies is proposed.

Novel biomarkers for the prediction of the spontaneous preterm birth phenotype: a systematic review and meta-analysis.

BACKGROUND: Being able to predict preterm birth is important, as it may allow a high-risk population to be selected for future interventional studies and help in understanding the pathways that lead to preterm birth. OBJECTIVE: To investigate the accuracy of novel biomarkers to predict spontaneous preterm birth in women with singleton pregnancies and no symptoms of preterm labour. SEARCH STRATEGY: Electronic searches in PubMed, Embase, Cinahl, Lilacs, and Medion, references of retrieved articles, and conference proceedings. No language restrictions were applied. SELECTION CRITERIA: Observational studies that evaluated the accuracy of biomarkers proposed in the last decade to predict spontaneous preterm birth in asymptomatic women. We excluded studies in which biomarkers were evaluated in women with preterm labour. DATA COLLECTION AND ANALYSIS: Two reviewers independently extracted data on study characteristics, quality, and accuracy. Data were arranged in 2 × 2 contingency tables and synthesised separately for spontaneous preterm birth before 32, 34, and 37 weeks of gestation. We used bivariate meta-analysis to estimate pooled sensitivities and specificities, and calculated likelihood ratios (LRs). MAIN RESULTS: A total of 72 studies, including 89,786 women and evaluating 30 novel biomarkers, met the inclusion criteria. Only three biomarkers (proteome profile and prolactin in cervicovaginal fluid, and matrix metalloproteinase-8 in amniotic fluid) had positive LRs > 10. However, each of these biomarkers was evaluated in only one small study. Four biomarkers had a moderate predictive accuracy (interleukin-6 and angiogenin, in amniotic fluid; human chorionic gonadotrophin and phosphorylated insulin-like growth factor binding protein-1, in cervicovaginal fluid). The remaining biomarkers had low predictive accuracies. CONCLUSIONS: None of the biomarkers evaluated in this review meet the criteria to be considered a clinically useful test to predict spontaneous preterm birth. Further large, prospective cohort studies are needed to evaluate promising biomarkers such as a proteome profile in cervicovaginal fluid.

Vaginal progesterone reduces the rate of preterm birth in women with a sonographic short cervix: a multicenter, randomized, double-blind, placebo-controlled trial.

OBJECTIVES: Women with a sonographic short cervix in the mid-trimester are at increased risk for preterm delivery. This study was undertaken to determine the efficacy and safety of using micronized vaginal progesterone gel to reduce the risk of preterm birth and associated neonatal complications in women with a sonographic short cervix. METHODS: This was a multicenter, randomized, double-blind, placebo-controlled trial that enrolled asymptomatic women with a singleton pregnancy and a sonographic short cervix (10-20 mm) at 19 + 0 to 23 + 6 weeks of gestation. Women were allocated randomly to receive vaginal progesterone gel or placebo daily starting from 20 to 23 + 6 weeks until 36 + 6 weeks, rupture of membranes or delivery, whichever occurred first. Randomization sequence was stratified by center and history of a previous preterm birth. The primary endpoint was preterm birth before 33 weeks of gestation. Analysis was by intention to treat. RESULTS: Of 465 women randomized, seven were lost to follow-up and 458 (vaginal progesterone gel, n=235; placebo, n=223) were included in the analysis. Women allocated to receive vaginal progesterone had a lower rate of preterm birth before 33 weeks than did those allocated to placebo (8.9% (n=21) vs 16.1% (n=36); relative risk (RR), 0.55; 95% CI, 0.33-0.92; P=0.02). The effect remained significant after adjustment for covariables (adjusted RR, 0.52; 95% CI, 0.31-0.91; P=0.02). Vaginal progesterone was also associated with a significant reduction in the rate of preterm birth before 28 weeks (5.1% vs 10.3%; RR, 0.50; 95% CI, 0.25-0.97; P=0.04) and 35 weeks (14.5% vs 23.3%; RR, 0.62; 95% CI, 0.42-0.92; P=0.02), respiratory distress syndrome (3.0% vs 7.6%; RR, 0.39; 95% CI, 0.17-0.92; P=0.03), any neonatal morbidity or mortality event (7.7% vs 13.5%; RR, 0.57; 95% CI, 0.33-0.99; P=0.04) and birth weight < 1500 g (6.4% (15/234) vs 13.6% (30/220); RR, 0.47; 95% CI, 0.26-0.85; P=0.01). There were no differences in the incidence of treatment-related adverse events between the groups. CONCLUSIONS: The administration of vaginal progesterone gel to women with a sonographic short cervix in the mid-trimester is associated with a 45% reduction in the rate of preterm birth before 33 weeks of gestation and with improved neonatal outcome.

Evidence-based intrapartum care in Cali, Colombia: a quantitative and qualitative study.

OBJECTIVES: To measure the rate of use of selected intrapartum obstetric practices and to explore the factors associated with their use. DESIGN: Prospective quantitative and qualitative study. SETTING: Fifteen public and private hospitals in Cali, Colombia. SAMPLE: Quantitative arm: 1,767 low-risk women delivering a single live baby; qualitative arm: 36 intrapartum care providers. METHODS: Quantitative analysis of women's clinical charts for measuring the rates of obstetric practices. Qualitative analysis of audiotaped semi-structured interviews with intrapartum care providers. MAIN OUTCOME MEASURES: Rates of use of ten intrapartum obstetric practices and associated factors and intrapartum care providers' views on evidence-based obstetric practice. RESULTS: Rates for the ineffective practices of enema use, perineal/pubic shaving, and routine intravenous infusion during labour were around 75%. Episiotomy rates for primiparae and multiparae were 70 and 22%, respectively. Rates for the beneficial practices of active management of the third stage of labour and allowing women's choice of position during the first stage of labour were around 45%. Companionship during labour, external cephalic version for breech presentation at term, and absorbable synthetic sutures for episiotomy showed rates of utilisation lower than 15%. Hospital characteristics, type of intrapartum care provider, and women's medical insurance status were associated with use of selected practices. Barriers and opportunities for implementing evidence-based practices in routine obstetric care were identified. CONCLUSIONS: Intrapartum care in Cali, Colombia, is not guided by the best available evidence. Effective change strategies should be undertaken to encourage the adoption of obstetric practices clearly demonstrated as effective and to discard those that are ineffective.

Effect of the interpregnancy interval after an abortion on maternal and perinatal health in Latin America.

OBJECTIVE: To investigate whether the length of the interval between an abortion and the next pregnancy is associated with increased risks of adverse maternal and perinatal outcomes in Latin America. METHOD: Retrospective cross-sectional study using information from 258,108 women delivering singleton infants and whose previous pregnancy resulted in abortion recorded in the Perinatal Information System database of the Latin American Centre for Perinatology and Human Development, Montevideo, Uruguay, between 1985 and 2002. Adjusted odds ratios were obtained through logistic regression analysis. RESULT: Compared with the post-abortion interpregnancy intervals of 18 to 23 months, intervals shorter than 6 months were significantly associated with increased risks of maternal anemia, premature rupture of membranes, low birth weight, very low birth weight, preterm delivery, and very preterm delivery. CONCLUSION: In Latin America, post-abortion interpregnancy intervals shorter than 6 months are independently associated with increased risks of adverse maternal and perinatal outcomes in the next pregnancy. DEFINITION: Post-abortion interpregnancy interval (PAII): the time elapsed between the day of the abortion and the first day of the last menstrual period for the index pregnancy.

Case-control study of risk factors for complicated eclampsia.

OBJECTIVE: To identify risk factors associated with complicated eclampsia. METHODS: Twenty-four patients with eclampsia complicated by intracerebral hemorrhage, pulmonary edema, renal, hepatic, or respiratory failure, disseminated intravascular coagulation, abruptio placentae, pulmonary aspiration, or hemolysis, elevated liver enzymes, low platelets syndrome were compared retrospectively with 101 uncomplicated eclamptic controls. Information on maternal demographic factors, medical and obstetric histories, and maternal and perinatal outcomes was retrieved and analyzed by univariate and multivariate analysis. RESULTS: By multiple logistic regression, the only risk factors associated with the development of complicated eclampsia were maternal age over 26 years (adjusted odds ratio [OR] 6.3, 95% confidence interval [CI] 2.17, 18.48), multiparity (adjusted OR 4.5, 95% CI 1.55, 13.60) and no prenatal care (adjusted OR 3.3, 95% CI 1.25, 9.60). CONCLUSION: Maternal age above 26 years, multiparity, and no prenatal care are the maternal risk factors identified for the development of complicated eclampsia.

Maternal morbidity and mortality associated with multiple gestations.

OBJECTIVE: To test the hypothesis that women with multiple gestations are at increased risk of adverse maternal outcomes. METHODS: We studied the association between multiple gestation and frequency of adverse maternal outcomes in 885,338 pregnancies recorded in the Perinatal Information System database of the Latin American Center for Perinatology and Human Development, Montevideo, Uruguay, between 1985 and 1997. Relative risks (RRs) were adjusted for 14 potential confounding factors through multiple logistic regression models. RESULTS: There were 15,484 multiple gestations. Among parous women, multiple gestation was associated with a twofold increase in risk of death compared with singleton gestations [adjusted RR 2.1; 95% confidence interval (CI) 1.1, 3.9]. Compared with singleton gestations, women with multiple gestations had adjusted RRs of 3.0 (95% CI, 2.9, 3.3) for eclampsia, 2.2 (95% CI, 1. 9, 2.5) for preeclampsia, and 2.0 (95% CI, 1.9, 2.0) for postpartum hemorrhage. Likewise, there was significant association between multiple gestation and increased incidence of preterm labor, anemia, urinary tract infection, puerperal endometritis, and cesarean delivery. The incidences of premature rupture of membranes, third-trimester bleeding, and gestational diabetes mellitus were not statistically different for singleton and multiple gestations. CONCLUSION: Multiple gestation increases the risk of significant maternal morbidity and mortality.

Evaluation of methods used in the prediction of hypertensive disorders of pregnancy.

Several methods used in the prediction of hypertensive disorders of pregnancy (HDP) were evaluated with statistical techniques. Only cohort studies were considered. The data reviewed show that platelet count, hematocrit, serum uric acid, and microalbuminuria are poor predictors of HDP. Mean arterial pressure predicts transient hypertension rather than preeclampsia. Fibronectin, urinary calcium excretion, roll-over test, and Doppler ultrasound showed contradictory and nonconclusive findings among the different authors. Isometric exercise test showed high predictive values but only two studies have been performed. Angiotensin II sensitivity was the test that showed the best predictive values but it is useless in clinical practice. In conclusion, currently, there is no test that fulfills all criteria established to be a good predictor of hypertensive disorders of pregnancy. The search for an adequate method for the screening of HDP with a high sensitivity, inexpensive, and easy to perform should still be a priority in future investigations.

Triple-marker test as screening for Down syndrome: a meta-analysis.

The effectiveness of triple-marker testing as screening for Down syndrome needs to be evaluated by means of formal meta-analytic techniques. We did a MEDLINE search to identify studies evaluating the detection of Down syndrome by use of the triple-marker test. Reference lists of articles were also checked. Papers published in either English, French, or German from 1966 to November 1996 were eligible for this review. Twenty cohort studies were identified. Results of sensitivities and false-positive rates from different subgroups of the study sample were compared by using summary receiver-operating characteristic curve analysis. Medians of sensitivities and false-positive rates were also estimated. A total of 194,326 patients were included. In women of all ages, the medians for sensitivities were 67, 71, and 73 percent when the cutoffs used were 1:190-200, 1:250-295, and 1:350-380, respectively. The median false-positive rates fluctuated between 4 and 8 percent. For women at or above 35 years old, the medians of sensitivity and false-positive rate were 89 and 25 percent, respectively, when the chosen cutoff was 1:190-200. In patients below 35 years old, the median sensitivity was 57 percent if the cutoff used was 1:250-295. Summary receiver-operating characteristic curves showed that 1:190 was the best cutoff for predicting Down syndrome. The triple-marker testing is an effective screening method of detecting Down syndrome pregnancies. It is less effective in younger than in older age groups and may be offered as an alternative to amniocentesis to pregnant women over 35.