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.

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.

Monitoring data and safety in the WHO Antenatal Care Trial.

A committee to monitor data and safety in a large clinical trial should have members with expertise in biostatistics, epidemiology and the clinical field relevant to the trial. Its mandate should cover both logistics and the safety of study subjects, issues which to some extent overlap. While a steering committee and field staff members ideally should be blinded to the experimental and control arms of a randomised clinical trial, the data and safety monitoring committee (DSMC) should have full access to interim trial data to fulfil its role as watchdog. One initial question to be resolved concerns if and when to advise stopping a trial because of danger to study subjects, or on the other hand obvious benefits, in one trial arm. The DSMC of the WHO Antenatal Care Trial decided not to establish any definite stopping rules before implementation. After a scrutiny of the adopted procedures for data collection and handling, the DSMC received monthly reports of recruitment, and individual summary reports of three adverse events by site and trial arm: maternal deaths, fetal deaths and cases of eclampsia. At the time of writing (December 1997) recruitment to the trial is almost complete, but data collection will continue throughout most of 1998, until every index pregnancy has ended in birth or miscarriage. So far, the balance of untoward events between the intervention and control arms have not given cause for alarm.