Effect of sibship asthma on newborns with transient tachypnea of the newborn (TTN).

BACKGROUND: A number of studies have demonstrated that transient tachypnea of the newborn (TTN) is a risk factor for later asthma. The present study attempts to determine whether older sibling asthma is a risk factor for TTN.

METHODS: Medical records of 1318 newborns from neonatal intensive care and delivery units were studied. None of the subjects were first-born, and thus, all had older siblings. Clinical data of mothers and their children were obtained from medical records. Data items included date of birth, gestational age (GA) at birth, birth weight, gender, mode of delivery including Normal Spontaneous Delivery or caesarean section (CS) and whether pre-labour CS or not, reasons for CS, number of pregnancies, number of children, asthma of mothers and siblings, whether the newborn had TTN or not. Logistic regression analysis was used to assess the association between siblings' asthma and TTN.

RESULTS: Pre-labour CS, maternal asthma, GA, babies with large and small birth weight for GA, number of pregnancies and children (three and more) were found to be significantly associated with TTN. Siblings' asthma was found to be independently associated with a diagnosis of TTN.

CONCLUSIONS: Both pre-labour CS and mothers with asthma were common risk factors for the development of TTN. An association was present between TTN and siblings' asthma even in infants whose mothers did not have asthma.