Obstetric risk factors for periventricular leukomalacia among preterm infants.

OBJECTIVE

To evaluate the obstetric antecedents of cystic periventricular leukomalacia and transient echodense periventricular lesions among preterm infants.

DESIGN

A cohort study of preterm singleton infants born between 25 and 33 weeks gestation.

SETTING

Pavia, Italy.

POPULATION

Three hundred and forty-nine infants admitted to a Division of Neonatal Intensive Care who were screened for periventricular leukomalacia.

METHOD

The obstetric factors in infants with either cystic periventricular leukomalacia or transient echodense periventricular lesions were compared to those in infants with negative cranial ultrasonographic findings. Stepwise multiple logistic regression analysis was used to evaluate the association between risk factors and outcomes adjusting for confounders.

RESULTS

The prevalence of cystic periventricular leukomalacia and transient echodense lesions was 5.7% (20/349) and 14% (49/349), respectively. The main risk factors for cystic leukomalacia were first trimester haemorrhage (OR 4.49; 95% CI 1.63-12.39), maternal urinary tract infection on admission (OR 5.71; 95% CI 1.91-17.07), and neonatal acidosis (pH < 7.2) at birth (OR 5.97; 95% CI 1.93-18.52). Meconium-stained amniotic fluid (OR 3.95; 95% CI 1.42-10.98) and long term (> 72 hours) ritodrine tocolysis (OR 2.54; 95% CI 1.28-5.05) were associated with an increased risk of echodense lesions. The likelihood of overall leukomalacia (cystic plus echodense periventricular lesions) was increased among cases with meconium-stained amniotic fluid (OR 4.06; 95% CI 1.65-10.0), long-term ritodrine tocolysis (OR 2.56; 95% CI 1.38-4.72), maternal infection (OR 1.73; 95% CI 1.0-3.0), and acidosis at birth (OR 1.98; 95% CI 1.0-3.98).

CONCLUSIONS

This study confirms that maternal infection, acidosis at birth, and meconium-stained amniotic fluid increase the risk of periventricular leukomalacia in preterm infants. Long-term ritodrine use seems to increase the risk for transient echodense lesions.