Labour outcome of low-risk multiparas of 40 years and older. A case-control study.

Between January 1, 1994 and December 31, 1997 a total of 76 low-risk multiparas of 40 years and older with spontaneous onset of labour were delivered and were compared with 152 younger (25-30 years-old) low-risk multiparas of similar parity in a case-control study. The labour and perinatal outcomes of the 2 groups were compared. The duration of the first stage of labour was longer (233 minutes versus 149 minutes, p<0.0005) in the older women. Significantly more labours of older multiparas were complicated by intrapartum fetal distress (6.6% versus 1.3%, p<0.05); received intramuscular analgesia (11.8% versus 2.6%, p<0.01); and had operative deliveries (17.1% versus 4.6%, p<0.01). The incidence of instrumental delivery (11.8% versus 3.9%, p<0.05) and Caesarean section (5.3% versus 0.7%, p<0.05) were higher among older multiparas. The incidences of Syntocinon augmentation of labour, prolonged second stage, episiotomy and third stage complications such as perineal tear, primary postpartum haemorrhage, and retained placenta were similar in both groups. Both groups had similar perinatal outcomes. These women should be treated as others with high-risk pregnancies with appropriate careful attention during labour such as continuous fetal heart rate monitoring. They should be counselled to be made aware of the increased risks during labour.