Abstract: We included seven trials (more than 60,000 women): four in high-income countries with individual randomisation; three in low- and middle-income countries with cluster randomisation (clinics as the unit of randomisation). Most of the data included in the review came from the three large, well-designed cluster-randomised trials that took place in Argentina, Cuba, Saudi Arabia, Thailand and Zimbabwe. All results have been adjusted for the cluster design effect. All of the trials were at some risk of bias as blinding of women and staff was not feasible with this type of intervention. For primary outcomes, evidence was graded as being of moderate or low quality, with downgrading decisions due to risks of bias and imprecision of effects. The number of visits for standard care varied, with fewer visits in low- and middle- income country trials. In studies in high-income countries, women in the reduced visits groups, on average, attended between 8.2 and 12 times. In low- and middle- income country trials, many women in the reduced visits group attended on fewer than five occasions, although in these trials the content as well as the number of visits was changed, so as to be more 'goal-oriented'. Perinatal mortality was increased for those randomised to reduced visits rather than standard care, and this difference was borderline for statistical significance (risk ratio (RR) 1.14; 95% confidence interval (CI) 1.00 to 1.31; five trials, 56,431 babies; moderate-quality evidence). In the subgroup analysis, for high-income countries the number of deaths was small (32/5108), and there was no clear difference between the groups (RR 0.90; 95% CI 0.45 to 1.80, two trials); for low- and middle-income countries perinatal mortality was significantly higher in the reduced visits group (RR 1.15; 95% CI 1.01 to 1.32, three trials). There was no clear difference between groups for our other primary outcomes: maternal death (RR 1.13, 95%CI 0.50 to 2.57, three cluster-randomised trials, 51,504 women, low-quality evidence); hypertensive disorders of pregnancy (various definitions including pre-eclampsia) (RR 0.95, 95% CI 0.80 to 1.12, six studies, 54,108 women, low-quality evidence); preterm birth (RR 1.02, 95% CI 0.94 to 1.11; seven studies, 53,661 women, moderate-quality evidence); and small-for-gestational age (RR 0.99, 95% CI 0.91 to 1.09, four studies 43,045 babies, moderate-quality evidence). Reduced visits were associated with a reduction in admission to neonatal intensive care that was borderline for significance (RR 0.89; 95% CI 0.79 to 1.02, five studies, 43,048 babies, moderate quality evidence). There were no clear differences between the groups for the other secondary clinical outcomes. Women in all settings were less satisfied with the reduced visits schedule and perceived the gap between visits as too long. Reduced visits may be associated with lower costs. In settings with limited resources where the number of visits is already low, reduced visits programmes of antenatal care are associated with an increase in perinatal mortality compared to standard care, although admission to neonatal intensive care may be reduced. Women prefer the standard visits schedule. Where the standard number of visits is low, visits should not be reduced without close monitoring of fetal and neonatal outcome.

Plain-language summary: The review set out to compare studies where women receiving standard care were compared with women attending on a reduced number of occasions. We included seven randomised controlled trials involving more than 60,000 women. We assessed studies for risk of bias and graded the quality of the evidence. The trials were carried out in both high-income (four trials) and low- and middle-income countries (three trials). In high-income countries the number of visits was reduced to around eight. In lower-income countries many women in the reduced visits group attended for care on fewer than five occasions, although the content of visits was altered so as to focus on specific goals. In this review there was no strong evidence of differences between groups receiving a reduced number of antenatal visits compared with standard care on the number of preterm births or low birthweight babies (moderate-quality evidence). However, there was some evidence from these trials that in low- and middle-income countries perinatal mortality may be increased with reduced visits (low-quality evidence) although there may have been fewer admissions to neonatal intensive care but the evidence for this latter outcome was not strong. There was no clear difference between groups for our other primary outcomes including maternal death and hypertensive disorders of pregnancy (including pre-eclampsia). There was evidence that women in all settings were less satisfied with the reduced schedule of visits; for some women the gap between visits was perceived as too long. Reduced visits may be associated with lower costs.