Risk assessment at the end of pregnancy is a poor predictor for complications at delivery

To evaluate the usefulness of prenatal risk assessment for prediction of need for obstetric interventions.

Area based retrospective study.

Västerås Central Hospital, Sweden, with all antenatal care units in the area.

All women delivered at the only delivery ward in the area, after attending antenatal care at the affiliated ANC-units in 1990 (n = 2008) and 1992 (n = 1874).

Obstetric interventions at delivery.

During the two years 81% and 83% of the study population delivered an infant in vertex presentation at term but 15% and 17% without risk factors or complications at the end of pregnancy had complications during delivery. The relative risk for interventions when risk factors were present was 2.2 and with spontaneous onset of labor 1.3/1.4. Low risk primiparae had unforeseen complications in 25% and multiparae in 10%. Relative risk for multiparae with risk factors and spontaneous labor was 2.2/1.8 and for primiparae 1.4/1.6.

Individual prediction of obstetric emergencies has low accuracy, which should be included in the information to women as well as in discussions with health pianners.