Authors:
Hammond G, Langridge A, Leonard H, Hagan R, Jacoby P, de Klerk N, Pennell C, Stanley F
Authors notes:
BJOG: An International Journal of Obstetrics and Gynaecology. 2013;120(9):1051-1060
Keywords:
Antecedents, Labour onset, Medically indicated, Population attributable risk, Prelabour rupture of membranes, Preterm birth
Abstract:
To characterise changing risk factors of preterm birth in Western Australia between 1984 and 2006.
Marked increases in maternal age and primiparous births were observed. A four-fold increase in the rates of pre-existing medical complications over time was observed.
Rates of pregnancy complications remained stable.
Multinomial regression showed differences in antecedent profiles across labour onset types.
PAF estimates indicated that 50% of medically indicated preterm deliveries could be eliminated after removing six antecedents from the population; estimates for PROM and spontaneous preterm reduction were between 10 and 20%.
Variables pertaining to previous and current obstetric complications (previous preterm birth, previous caesarean section, pre-eclampsia and antepartum haemorrhage) were the most influential predictors of preterm birth and adverse labour onset (PROM and medically indicated).
Preterm antecedent profiles have changed markedly over the 23 years studied.
Some changes may be attributable to true change, others to advances in surveillance and detection.
Still others may signify change in clinical practice.