Thyroid-stimulating hormone levels in the first days of life and perinatal factors associated with sub-optimal neuromotor outcome in pre-term infants.

Abstract

To identify perinatal factors associated with sub-optimal neuromotor outcome in infants without evident central nervous system lesions (intraventricular hemorrhage/ periventricular leukomalacia), with gestational age ≤30 (group I) and of 31-32 weeks (group II). A total of 102 premature infants admitted to the Neonatal Intensive Care Unit of Pisa, at 26-32 weeks of gestation, were studied. Data about perinatal factors and TSH values at 3-4 days of life were collected. The assessment of neuromotor development was performed at 18 months of corrected age, using the locomotor subscale of the Griffiths Scales of Mental Development. Risk factors supposed to be predictive of sub-optimal neuromotor outcome (odds ratio >1) were at ≤30 weeks: male sex, small for gestational age, patent duct arterious, respiratory distress syndrome, and at 31-32 weeks: Apgar at 5 min <7, respiratory distress syndrome, patent duct arterious and birth weight <1500 g. A strong correlation was also found between TSH screening values >4,3 mU/l and suboptimal neuromotor outcome in both groups. Several perinatal factors, acting on an immature and more vulnerable nervous system, such as the pre-term one, different for different gestational ages, are associated with a sub-optimal neuromotor outcome. Higher, but within the normal range, TSH values at screening seem to be a strong risk factor for neuromotor outcome in preterm infants without intraventricular hemorrhage or periventricular leukomalacia.