During the first week of life serum calcium, phosphorus, magnesium, immunoreactive thyrocalcitonin hormone, and parathyroid hormone concentrations were determined daily in 36 preterm and 29 small for gestational age, full term, healthy infants. Preterm babies with early neonatal hypocalcaemia had significantly higher concentrations of serum thyrocalcitonin hormone in the first four days of life...
