Unbooked mothers and their babies--what causes the poor outcomes?

To compare perinatal outcome between booked and unbooked mothers of similar gestational age using birth weight as a proxy for gestational age.

91 unbooked mothers were obtained from a pool of 2,054 mothers from the Chiawelo district in Soweto delivered consecutively at the local community clinic or at Baragwanath, the referral hospital. For each of these, a single booked control from the same pool was found, matched to within 50 g birth weight. Detailed information from case notes was used to compare the two groups and their perinatal outcomes.

Unbooked mothers tended to be at lower obstetric risk. None of the unbooked versus 10 of the booked mothers had a poor obstetric history (2 previous abortions or a previous perinatal death). There was a trend to more twin pregnancies (5 v. 1) and more previous caesarean sections (12 v. 8) in the booked mothers. Perinatal mortality rates were not significantly different (unbooked 258/1,000; booked 268/1,000). Perinatal morbidity, as assessed on the basis of need for neonatal admission and ventilation, was similar in the two groups.

Booked mothers were at higher risk, with worse obstetric histories, which probably influenced their decisions to book for antenatal care. Unbooked mothers seemed to be at lower risk, often presenting 'unbooked' because of preterm complications. Many of the latter would probably have booked had their pregnancies advanced uneventfully. As such, unbooked status should not be regarded as a high-risk, poor prognostic category. These mothers and their babies should therefore receive the same perinatal care as booked patients.