ObjectiveTo comare safety and cost-effectiveness of domiciliary antenatal fetal monitoring (cardiotocography and obstetric surveillance) with in-hospital monitoring in high-risk pregnancies.MethodsFrom September 1992 to June 1994, 150 consecutive women with high-risk pregnancies, who would other wise be monitored in the hospital, entered a randomized controlled trial of in-hospital (n= 76) monitoring. The main outcome measures were neonatal safety (Prechtl neurologic optimality score, the proportion of non-optimals) and cost-effectiveness. To test a two-point defference in mean Prechtl scores (two-tailed α = .05, 1-β = .80), 150 women were needed. Safety and cost-effectiveness were analyzed according to intention to treat. Conditional on the safety outcomes, a cost-minimization analyses based on actual resource use was performed. Uncertainty of results was explored by sensitivity analyses.ResultsNeonatal outcomes were equal. No cost-shifting between the antenatal and psotpartum period occurred. Substituting domiciliary for in-hospital monitoring reduced mean (standard deviation) antenatal costs from $3558 ($2841) to $1521 ($1459) per woman (P< .01). If costs were varied by the addition of 50%, costs were still reduced. The magnitude of the reduction was sensitive to the costs of domiciliary monitoring.ConclusionDomiciliary monitaring is safe and reduces costs by one-half. The technique seems transferable to other settings but local circumstances may sometimes hamper its dissemination.