The epidemiology of syphilis in pregnancy.

This study evaluated the magnitude, risk factors and outcomes of syphilis in pregnancy in a large cohort of women in four countries participating in the World Health Organization (WHO) antenatal care trial. All women attending the first prenatal care at each selected clinic were enrolled. Screening at the first antenatal visit was routinely performed with either rapid plasma reagin or Venereal Disease Research Laboratory and confirmed by fluorescent treponemal antibody absorption. All women also had the same syphilis tests after delivery. The initial prevalence, the incidence during pregnancy and the overall prevalence of syphilis at delivery were 0.9%, 0.4% and 1.3% respectively. Risk factors for syphilis during pregnancy were younger age for the incidence and older age and a history of stillbirth for the prevalence. Women with syphilis during pregnancy had significantly more adverse outcomes. We support the recommendation that in addition to the initial testing, a second routine test for syphilis ought to be established early in the third trimester even in low prevalence areas.

WHO antenatal care randomised trial for the evaluation of a new model of routine antenatal care.

BACKGROUND: We undertook a multicentre randomised controlled trial that compared the standard model of antenatal care with a new model that emphasises actions known to be effective in improving maternal or neonatal outcomes and has fewer clinic visits. METHODS: Clinics in Argentina, Cuba, Saudi Arabia, and Thailand were randomly allocated to provide either the new model (27 clinics) or the standard model currently in use (26 clinics). All women presenting for antenatal care at these clinics over an average of 18 months were enrolled. Women enrolled in clinics offering the new model were classified on the basis of history of obstetric and clinical conditions. Those who did not require further specific assessment or treatment were offered the basic component of the new model, and those deemed at higher risk received the usual care for their conditions; however, all were included in the new-model group for the analyses, which were by intention to treat. The primary outcomes were low birthweight (<2500 g), pre-eclampsia/eclampsia, severe postpartum anaemia (<90 g/L haemoglobin), and treated urinary-tract infection. There was an assessment of quality of care and an economic evaluation. FINDINGS: Women attending clinics assigned the new model (n=12568) had a median of five visits compared with eight within the standard model (n=11958). More women in the new model than in the standard model were referred to higher levels of care (13.4% vs 7.3%), but rates of hospital admission, diagnosis, and length of stay were similar. The groups had similar rates of low birthweight (new model 7.68% vs standard model 7.14%; stratified rate difference 0.96 [95% CI -0.01 to 1.92]), postpartum anaemia (7.59% vs 8.67%; 0.32), and urinary-tract infection (5.95% vs 7.41%; -0.42 [-1.65 to 0.80]). For pre-eclampsia/eclampsia the rate was slightly higher in the new model (1.69% vs 1.38%; 0.21 [-0.25 to 0.67]). Adjustment by several confounding variables did not modify this pattern. There were negligible differences between groups for several secondary outcomes. Women and providers in both groups were, in general, satisfied with the care received, although some women assigned the new model expressed concern about the timing of visits. There was no cost increase, and in some settings the new model decreased cost. INTERPRETATIONS: Provision of routine antenatal care by the new model seems not to affect maternal and perinatal outcomes. It could be implemented without major resistance from women and providers and may reduce cost.

WHO systematic review of randomised controlled trials of routine antenatal care.

BACKGROUND: There is a lack of strong evidence on the effectiveness of the content, frequency, and timing of visits in standard antenatal-care programmes. We undertook a systematic review of randomised trials assessing the effectiveness of different models of antenatal care. The main hypothesis was that a model with a lower number of antenatal visits, with or without goal-oriented components, would be as effective as the standard antenatal-care model in terms of clinical outcomes, perceived satisfaction, and costs. METHODS: The interventions compared were the provision of a lower number of antenatal visits (new model) and a standard antenatal-visits programme. The selected outcomes were pre-eclampsia, urinary-tract infection, postpartum anaemia, maternal mortality, low birthweight, and perinatal mortality. We also selected measures of women's satisfaction with care and cost-effectiveness. This review drew on the search strategy developed for the Cochrane Pregnancy and Childbirth Group of the Cochrane Collaboration. FINDINGS: Seven eligible randomised controlled trials were identified. 57418 women participated in these studies: 30799 in the new-model groups (29870 with outcome data) and 26619 in the standard-model groups (25821 with outcome data). There was no clinically differential effect of the reduced number of antenatal visits when the results were pooled for pre-eclampsia (typical odds ratio 0.91 [95% CI 0.66-1.26]), urinary-tract infection (0.93 [0.79-1.10]). postpartum anaemia (1.01), maternal mortality (0.91 [0.55-1.51]), or low birthweight (1.04 [0.93-1.17]). The rates of perinatal mortality were similar, although the rarity of the outcome did not allow formal statistical equivalence to be attained. Some dissatisfaction with care, particularly among women in more developed countries, was observed with the new model. The cost of the new model was equal to or less than that of the standard model. INTERPRETATION: A model with a reduced number of antenatal visits, with or without goal-oriented components, could be introduced into clinical practice without risk to mother or baby, but some degree of dissatisfaction by the mother could be expected. Lower costs can be achieved.

Methodological considerations on the design and analysis of an equivalence stratified cluster randomization trial.

The World Health Organization and collaborating institutions in four developing countries have conducted a multi-centre randomized controlled trial, in which clinics were allocated at random to two antenatal care (ANC) models. These were the standard 'Western' ANC model and a 'new' ANC model consisting of tests, clinical procedures and follow-up actions scientifically demonstrated to be effective in improving maternal and newborn outcomes. The two models were compared using the equivalence approach. This paper discusses the implications of the equivalence approach in the sample size calculation, analysis and interpretation of results of this cluster randomized trial. It reviews the ethical aspects regarding informed consent, concluding that the Zelen design has a place in cluster randomization trials. It describes the estimation of the intracluster correlation coefficient (ICC) in a stratified cluster randomized trial using two methods and reports estimates of the ICC obtained for many maternal, newborn and perinatal outcomes. Finally, it discusses analytical problems that arose: issues encountered using a composite index, heterogeneity of the intervention effect across sites, the choice of the method of analysis and the importance of efficacy analyses. The choice of the clustered Woolf estimator and the generalized estimating equations (GEE) as the methods of analysis applied is discussed.

The WHO antenatal care randomised controlled trial: rationale and study design.

The World Health Organisation and collaborating institutions in developing countries are conducting a multicentre randomised controlled trial to evaluate a new antenatal care (ANC) programme, consisting of tests, clinical procedures and follow-up actions scientifically demonstrated to be effective in improving maternal and newborn outcomes. These activities are distributed, for practical reasons, over four visits during the course of pregnancy and are aimed at achieving predetermined goals. The study is taking place in four countries, Argentina, Cuba, Saudi Arabia and Thailand. Recruitment of study subjects started on 1 May 1996. All 53 ANC clinical units had been enrolled by December 1996. Clinics in each country were randomly allocated (cluster randomisation) to provide either the new programme or the traditional programme currently in use. Approximately 24,000 women presenting for ANC at these clinics over an average period of 18 months will have been recruited. As women attending the control clinics receive the 'best standard treatment' as currently offered in these clinics, individual informed consent is requested only from women attending the intervention clinics. Authorities of the corresponding health districts and all participating clinics have provided written institutional informed consent before randomisation. The primary outcome of the trial in relation to maternal conditions is the rate of a morbidity indicator index, defined as the presence of at least one of the following conditions for which ANC is relevant: (a) pre-eclampsia or eclampsia during pregnancy or within 24 h of delivery; (b) postpartum anaemia (haemoglobin < 90 g/L); or (c) severe urinary tract infection/pyelonephritis, defined as an episode requiring antibiotic treatment and/or hospitalisation. The primary fetal outcome is the rate of low birthweight (< 2500 g). Adverse maternal and fetal outcomes are expected for approximately 10% of the control group. Several maternal and perinatal secondary outcomes are also considered. A comprehensive cost-effectiveness analysis and women's and providers' satisfaction evaluation are performed concurrently with the trial. Health-care programmes should be rigorously evaluated by randomised controlled trials, which are feasible in developing countries and should be conducted before introducing new treatments or health interventions.

PIP: The procedures and examinations included in currently practiced prenatal care have not been subjected to systematic, scientifically rigorous evaluation. The World Health Organization (WHO) Antenatal Care Randomized Controlled Trial is evaluating a new prenatal care regimen with demonstrated efficacy in improving maternal and newborn outcomes. Program activities include screening for health conditions that increase the risk of specific adverse pregnancy outcomes, therapeutic interventions known to affect these outcomes beneficially, and education of pregnant women regarding potential health emergencies and appropriate responses. The study's hypothesis is that the tests, clinical procedures, and follow-up actions associated with this approach, delivered over the course of four visits during pregnancy, are more effective than the traditional prenatal care package in terms of specific maternal and perinatal results without being more expensive. This paper addresses the rationale, design, and methodology of this trial. 53 prenatal care clinics in four well-defined geographic areas (Khon Kaen Province, Thailand; Havana, Cuba; Rosario, Argentina; and Jeddah, Saudi Arabia) have been randomized to the two arms of the study. By the end of 1997, 24,000 women presenting for prenatal care at these sites had been enrolled. The primary maternal outcome is the morbidity indicator index, defined as the presence of at least one of the following conditions: pre-eclampsia or eclampsia during pregnancy or within 24 hours of delivery, postpartum anemia, or severe urinary tract infection/pyelonephritis. The primary fetal outcome is the rate of low birth weight. A comprehensive cost-effectiveness analysis and provider satisfaction evaluation will be performed concurrently with the trial. Data collection will be completed in 1998.

Methodological considerations in the design of the WHO Antenatal Care Randomised Controlled Trial.

We discuss methodological issues arising in a recent evaluation trial of a new antenatal care programme, as sponsored by the Special Programme of Research, Development and Research Training in Human Reproduction, and WHO's Division of Reproductive Health (Technical Support). The randomisation unit for the trial is the antenatal care clinic, with 53 clinics located in four countries randomly allocated to provide either the new programme or the traditional programme currently in use. Approximately 24,000 women presenting for antenatal care over an average period of 18 months will have been recruited.

PIP: The World Health Organization (WHO) Antenatal Care Randomized Controlled Trial is evaluating the impact of a new program of prenatal care on the health of mothers and newborns. Study subjects will receive either the standard prenatal care program currently offered at participating sites or a new regimen comprised of scientifically evaluated, objective-oriented prenatal care services. A total of 24,000 pregnant women from 53 prenatal care clinics in Argentina, Cuba, Thailand, and Saudi Arabia have been enrolled and stratified on the basis of the number of pregnant women enrolled in each clinic during the year preceding the study, the type of clinic (free-standing or hospital), and the administrative health system to which they belong. This article discusses methodological issues related to the study's design, with emphasis on sample size considerations, planned approaches to the statistical analysis, and data quality control. The rationales for selecting clinics as the unit of randomization are to reduce the risk of treatment contamination, encourage participation, and facilitate administrative and logistic convenience in the implementation of the intervention. Randomization of intact clinics to different intervention groups with predefined strata reflects the fact that the aim of the trial is to show the equivalence, not necessarily the superiority, of the new prenatal care program with the existing program of standard care. The two major adverse outcomes, a high maternal morbidity index and low birth weight, are expected to be in the range of 10%. To ensure that a statistically nonsignificant effect can be interpreted meaningfully, the trial has been designed to have a 90% power for ruling out an absolute difference of at least 0.02 in the expected incidence of the primary end points. A confidence interval approach was selected for sample size estimation, as recommended for equivalence trials, to provide additional assurance that the sample size is adequate.

The practice of antenatal care: comparing four study sites in different parts of the world participating in the WHO Antenatal Care Randomised Controlled Trial.

In the preparation of a randomised controlled trial to evaluate a new programme of antenatal care (ANC) in different parts of the world, we conducted a baseline survey of the ANC procedures in all 53 clinics participating in the trial. There were two components of this survey: (1) description of clinic characteristics and services offered: the staff of each clinic was interviewed and direct observation was made by field supervisors, and (2) the actual use of services by pregnant women attending these clinics: we reviewed a random sample of 2913 clinical histories. The clinical units surveyed were offering most of the activities, screening, laboratory tests and interventions recommended as effective according to the Cochrane Pregnancy and Childbirth Database (PCD), although some of these were not available in some sites. On the other hand, some tests and interventions that are considered not effective according to these criteria are reportedly offered. There was a difference across sites in the availability and offer to low-risk women of vaginal examination, evaluation of pelvic size, dental examination, external version for breech presentation and formal risk score classification, and a notable difference in the type of principal provider of ANC. There was a large variation in the actual use of screening and laboratory tests and interventions that should be offered to all women according to Cochrane PCD criteria: some of these are simply not available in a site; others are available, but only a fraction of women attending the clinics are receiving them. The participating sites all purport to follow the traditional 'Western' schedule for ANC, but in three sites we found that a high percentage of women initiate their ANC after the first trimester, and therefore do not have either the recommended minimum number of visits during pregnancy or the minimum first trimester evaluation. It is concluded that the variability and heterogeneity of ANC services provided in the four study sites are disturbing to the profession and cast doubts on the rationale of routine ANC.

PIP: This paper reports the results of an antenatal care (ANC) baseline survey in four study sites in different parts of the world participating in the WHO ANC randomized controlled trial. The health care units surveyed are providing most of the activities, screening, laboratory tests and interventions recommended as effective based on the Cochrane Pregnancy and Childbirth Database (PCD), although some of these are not available in some clinics. Some tests and interventions that are considered ineffective according to the PCD criteria are reportedly offered. A variation is observed across sites in the availability and offer to low-risk women of vaginal exam, pelvic size assessment, dental exam, external version for breech presentation, and formal risk score classification. Moreover, there is a significant difference in the type of principal ANC provider and a great variation in the actual performance of screening and laboratory tests and interventions that should be provided to all women according to these criteria. This is partly due to the unavailability of these services in the site, or only a fraction of women attending the clinics are receiving them. The participating clinics all declared to follow the traditional Western schedule for ANC; however, three clinics are found to have a high percentage of women who begin their ANC after the first trimester of pregnancy. It is generalized that the variability and heterogeneity of ANC services offered in the four sites are annoying to the profession and cast doubts on the rationale behind routine ANC.

The Latin American trial of psychosocial support during pregnancy: effects on mother's wellbeing and satisfaction. Latin American Network For Perinatal and Reproductive Research (LANPER).

A randomized controlled trial including 2235 women at high risk of low birthweight was conducted in four Latin American institutions. The objective of this trial was to evaluate a psychosocial support intervention during pregnancy aimed at improving perinatal health and mothers' psychosocial conditions. The core of the intervention was four to six home visits where emotional support, counseling and strengthening of the woman's social network was provided. Outcomes were measured at 36 weeks of pregnancy, post-partum and 40 days after delivery. The intervention was not successful in either altering women's perception of social support and satisfaction with the reproductive experience, as well as maternal and newborn's health care. It is concluded that although high levels of psychosocial distress during pregnancy may play an independent role in determining adverse pregnancy outcomes, this adverse effect does not appear to be ameliorated by psychosocial interventions conducted only during pregnancy, particularly those of a magnitude that can be realistically implemented (in content and frequency) at public care services in most developing countries.

Impact of health education during pregnancy on behavior and utilization of health resources. Latin American Network for Perinatal and Reproductive Research.

OBJECTIVE: Our purpose was to assess whether an intervention in the education of the mother and the support person involves a change in health-related behavior and use of health facilities. STUDY DESIGN: A randomized, controlled trial was conducted in four cities of Latin America on pregnant women at risk. Half of them (n = 1115) received a home intervention of four to six visits dealing with psychosocial support and education about health-related habits, alarm signs, hospital facilities, antismoking and antialcohol programs, and a reinforcement of adequate health services utilization for the pregnant woman and a support person. The control group (n = 1120) received routine prenatal care. RESULTS: The distribution of risk factors and demographic, obstetric, and psychologic characteristics at baseline was similar in both groups. Women in the intervention group showed a statistically significant better knowledge of seven of the nine alarm signs considered and of two of the three labor-onset signs required. No differences between groups were observed in improvement on diet, cigarette and alcohol consumption, maternal physical strain, lactation at 40 days postpartum, and utilization of health facilities. CONCLUSIONS: An intervention of psychosocial support and health education during pregnancy failed to show any benefit on perinatal outcome, health-related behavior, or utilization of health facilities.

The Latin American Multicenter Trial on psychosocial support during pregnancy: methodology and baseline comparability. Latin American Network for Perinatal and Reproductive Research (LANPER).

This article presents the methodology and baseline findings of a large multicenter trial involving four countries from Latin America (Argentina, Brazil, Cuba, and Mexico). The study was a randomized, controlled, single-masked trial to investigate the impact of social support during pregnancy on perinatal outcomes. Pregnant women with gestational ages between 15 and 22 weeks were screened in health facilities in the four countries. Those presenting with one or more risk factors for having a low-birthweight baby were invited to join the trial. A total of 2235 women--between 500 and 600 in each country--were randomized into an intervention (n = 1110) or a control (n = 1125) group. Both groups were comparable in terms of nearly all baseline variables. The intervention group received a minimum of four visits at home by a trained health worker who provided direct emotional support, health education, and an attempt to enhance the woman's social support network. Over 90% of all women were evaluated at 36 weeks of pregnancy and soon after delivery, and 85% at the 40th day postpartum. The outcomes under study included intrauterine growth retardation, gestational age, perinatal and maternal morbidity and mortality, labor interventions, psychological distress and characteristics of the social support network, among others. This trial showed that it was possible to select, screen, randomize, visit, and evaluate a large number of women in four Latin American countries using a standardized methodology.

The Latin American trial of psychosocial support during pregnancy: a social intervention evaluated through an experimental design.

Perinatal health problems are a public health priority in Latin America. Among the identified risk factors, psychological and social conditions play a crucial role. However, care during pregnancy and delivery in the region is usually hospital-centered and does not address women's psychological and social conditions. The preeminence of research on perinatal health, along with the necessity for testing interventions that represent alternative models to improve women's health, gave the Latin American Network for Perinatal and Reproductive Research grounds to develop a multicenter randomized controlled trial to evaluate a program of social support and health education during pregnancy. The conceptual framework for this study was based on an ecological model of social support, i.e. a model in which social support and health education play a synergistic role and are meant to modify stressful situations and negative health-related behaviors. The target population consisted of women attending obstetric hospitals before the 22nd gestational week, at high psychological and social risk (n = 2236). The intervention consisted of four to six home visits, carried out by social workers, and had four main components: the reinforcement of pregnant women's social support network, emotional support, health education, and the improvement of health services utilization. The main foci of the intervention were determined after an ethnographic study was carried out to identify stress-producing situations and needs for support during pregnancy. Besides the home visits, the program also offered a hot-line, an office in the hospital, a specially designed poster and booklet, and a 'guided tour' of the health institution. Since this was a multicenter trial, the program's standardization was a crucial methodological aspect that was achieved through the training course for the home-visitors team. Biological and psychosocial outcomes were measured in both experimental and control groups at the 36th week of gestational age, post-partum and at the 40th day after delivery. The attributes of the multicenter population showed an important variability, reflecting differences in the countries or hospitals' population prevalent attributes. The results of the program's implementation were analyzed, demonstrating that home visitors adapted topics discussed during the interviews to the women's conditions and the stage of pregnancy during which the visit took place.(ABSTRACT TRUNCATED AT 400 WORDS)

A randomized trial of psychosocial support during high-risk pregnancies. The Latin American Network for Perinatal and Reproductive Research.

BACKGROUND: It is often suggested that psychological and social support and health education for women at high risk for delivering a low-birth-weight infant can improve the outcomes of pregnancy, but the evidence is inconclusive. We undertook this prospective trial to evaluate a program of home visits designed to provide psychosocial support during pregnancy. METHODS: At four centers in Latin America, 2235 women at higher-than-average risk for delivering a low-birth-weight infant were recruited before the 20th week of pregnancy. The women were randomly assigned either to an intervention group (n = 1115) that received four to six home visits from a nurse or social worker in addition to routine prenatal care or to a control group (n = 1120) that received only routine prenatal care (with a mean of eight prenatal visits). The principal measures of outcome were low birth weight (< 2500 g), preterm delivery (< 37 weeks of gestation), and specified categories of maternal and neonatal morbidity. RESULTS: The women who received the home visits as well as routine prenatal care had outcomes that differed little from those of the women who received only routine care. The risks of low birth weight (odds ratio for the intervention group as compared with the control group, 0.93; 95 percent confidence interval, 0.68 to 1.28), preterm delivery (odds ratio, 0.88; 95 percent confidence interval, 0.67 to 1.16), and intrauterine growth retardation (odds ratio, 1.08; 95 percent confidence interval, 0.83 to 1.40) were similar in the two groups. There was no evidence that the intervention had any significant effect on the type of delivery, the length of hospital stay, perinatal mortality, or neonatal morbidity in the first 40 days. There was no protective effect of the psychosocial-support program even among the mothers at highest risk. CONCLUSIONS: Interventions designed to provide psychosocial support and health education during high-risk pregnancies are unlikely to improve maternal health or to reduce the incidence of low birth weight among infants.