The patient is a 1-week-old boy born at 37+2 weeks' gestational age through spontaneous vaginal delivery. The pregnancy was complicated by maternal gestational diabetes mellitus and pre-eclampsia. The Apgar score was 9 at both 1 minute and 5 minutes after birth. Because of hypoglycemia at delivery that required IV dextrose, he was admitted to the local neonatal intensive care unit. His blood glucose levels quickly stabilized, dextrose administration was discontinued, and the patient began breast-feeding. On day 2 of life, the patient began having intermittent oxygen desaturation, with oxygen saturation as measured by pulse oximetry down to 70% while sleeping; he was transferred to a tertiary-care NICU for further management. Aside from the hypoxia, he was otherwise asymptomatic. He was breast-feeding without difficulty and had no vomiting or gastroesophageal reflux; no cyanosis, stridor, or snoring; and no seizure-like activity or hypertonicity.