Gastroesophageal reflux (GER) has been found to be the causative factors of apnea, stridor, feeding intolerance, poor weight gain, and sudden infants death syndrome (SIDS) in infants. GER is a well-described in infants and children, but only scant mention of the premature infants with GER can be found in the literature.

Esophageal pH was measured during 24 hour in 21 healthy preterm infants, using a silicone microelectrode with an external reference electrode connected to a portable recorder. The mean age of the patients was 29±8 days, mean gestational age was 30⁺⁵±2⁺⁰ weeks, mean birth weight was 1,468±329 g, mean postconceptional age was 34⁺⁶±1⁺⁴ weeks and mean weight was 1,750±329 g. We evaluated the following reflux parameters; number of acid reflux, number of long acid reflux, longest acid reflux minutes, and reflux index.

Pathologic GER was detected in 12 (57%) subjects and most interesting parameters are reflux index and number of episodes with a pH<4 during 24 hour (high correlation with postprandial reflux index). Reflux was not correlated to gestational age, birth weight, age, postconceptional age, weight, sex and medication of the theophylline.

Gastroesophageal reflux is common in preterm infants, but it is usually not apparent, even with severe reflux.