Mrs.Jenner brings her 2-month-old infant to the clinic because she is concerned that he is spitting up too much after he feeds.What criteria will the nurse use to determine if an infant's regurgitation should be further investigated?

A) How often the baby spits up
B) How much the baby spits up at a time
C) The infant's weight gain
D) The consistency of the regurgitated matter

The most important criteria for determining if an infant's regurgitation should be further investigated is their weight gain. If the infant's weight gain is adequate, then the spitting up is likely not a cause for concern. However, if the infant is not gaining weight appropriately, further investigation may be necessary. Factors such as frequency, amount, and consistency of the regurgitation may also be considered, but they are not as significant as weight gain.