Assessment and care and major problems of the newborn practice

A boy born at 39 weeks by spontaneous vaginal birth is 60 hours old. He has a high-pitched cry, tremors when he is undressed, sneezes repeatedly and takes the breast poorly, latching and letting go. He has passed three loose stools since midnight. His temperature is 36.9 degrees, his capillary blood glucose is 3.7 mmol/L and his serum calcium is normal. Apgar scores were 9 and 9 and the cord arterial pH was 7.31. Membranes ruptured three hours before birth and his mother was afebrile throughout. Which one of the following items of history is most likely to explain his behaviour?