Past obstetric history and risk of perinatal death in Jamaica.

Singleton survivors born to multigravidae in the whole island of Jamaica in 2 months (September-October 1986) were compared with singleton perinatal deaths occurring to multigravidae throughout the island in the 12-month period September 1986 to August 1987. Past obstetric history was obtained from the mothers using a structured questionnaire. Deaths were categorised using the Wigglesworth classification. Logistic regression was used to compare current outcomes in women who had had at least one previous pregnancy. Antepartum fetal deaths with (1) outcome of last pregnancy; (2) previous Caesarean section; (3) previous stillbirth; and (4) increasing gravidity. In the presence of these factors maternal age ceased to be statistically significant. Deaths from immaturity were strongly associated with the past obstetric history, with increased risks for pregnancies to mothers with a history of previous miscarriage, perinatal death and premature live births. In general, however, the higher the gravidity the lower the risk. In the presence of these factors, maternal age showed no significant association. Intrapartum asphyxia was also associated with the outcome of the last pregnancy, history of prior stillbirth or neonatal death. First pregnancies were at significantly higher risk than second pregnancies (P < 0.05). For perinatal deaths as a whole, and in the presence of maternal age, the following were statistically significant independent factors: (1) the outcome of the immediately preceding pregnancy (high risks associated with prior miscarriage, stillbirth and premature live births); (2) previous Caesarean section (increased risk); (3) previous perinatal deaths; and (4) more than one prior early fetal loss. The results indicated that prior poor obstetric history bears similar risks of subsequent adverse outcome in the developing as in the developed world. There was no variation in risk, however, with interpregnancy interval or previous termination. Much of the variation in risk of perinatal death with maternal age among multigravidae appears largely to be secondary to past obstetric history.