Study designs of evaluations included in the review
The inclusion criteria for study design were not stated. Cohort studies and case series were included.
Specific interventions included in the review
Studies of free-standing MLMUs were eligible for inclusion. Studies of units attached to hospitals with an obstetric unit and of free-standing units with an on-site obstetrician were excluded.
Participants included in the review
The participants were women admitted to a free-standing MLMU. In general, they were at low obstetric risk (i.e. there had been no maternal, placental or neonatal complication during the present or previous pregnancies). In the included studies, women with multiple pregnancy were ineligible for MLMU. In three of the eight included studies, women with a first pregnancy were ineligible for MLMU admission.
In the controlled studies, the control group comprised women meeting MLMU eligibility criteria who delivered in hospital or at home.
Outcomes assessed in the review
Studies that assessed maternal and neonatal clinical outcomes were eligible for inclusion. Some studies included in the review assessed maternal and neonatal mortality and morbidity. All assessed intermediate outcomes such as maternal and neonatal transfer from an MLMU to an obstetric or neonatal unit, the use of different types of analgesia, and the requirement for Caesarean or instrumental delivery.
How were decisions on the relevance of primary studies made?
The authors did not state how the papers were selected for the review, or how many reviewers performed the selection.