Effect of latency period after premature rupture of membranes on 2 years infant mortality (DOMINOS study)

Objective: To assess the impact of a short latency period after preterm premature rupture of the membranes (PPROM) on infant mortality. Study design: A prospective cohort study of women with PPROM between 24017 and 3361 7 weeks' in singleton gestation was performed in all maternity wards of the Rhone-Alpes Region. Neonatal and infant outcomes were compared according to the latency period (< 48 h and > 48 h). The primary outcome was the mortality rate and the secondary outcome was a composite variable of significant neurological disorders at 2 years of age. Outcomes was stratified according to gestational age at rupture. Univariate and multiple logistic regression analyses were used with SAS statistical software. Results: Out of 471 women recruited in the study at a mean gestational age of 30.5 +/- 0.2 weeks, 170 (37%) presented with a < 48-h latency period, and 301 (63%), a >= 48-h latency period. While prior to 30 weeks' gestation, the mortality rate was higher in neonates with a short latency period (16.3% versus 7.3%, p < 0.01) with pulmonary disease being the major cause of death, a short latency period was associated with a lower mortality rate after 30 weeks' gestation (0% versus 3.7%, p = 0.02). After adjusting for confounding factors, a < 48-h latency period remained an independent factor associated with infant mortality prior to 30 week's gestation (odds ratio 3.8, 95% confidence interval 1.3-11.7). Significant neurological disorders were not modified by the length of the latency period. Conclusion: For PPROM that occur before 30 weeks' gestation, a short latency period was associated with a higher infant mortality rate. Inversely, it was associated with a lower mortality rate after 30 weeks'. There is an urgent need for a thorough evaluation of expectant management of PPROM after 30 weeks' gestation. (c) 2006 Published by Elsevier Ireland Ltd.