Final answer:
The PNP should reassure the mother that the infant's weight trajectory is normal, with an expected initial weight loss followed by a gradual gain. Increased intervention is not needed yet, given the infant is nursing well and already starting to gain weight back.
Step-by-step explanation:
The primary care PNP should reassure the mother about normal weight loss in the newborn. As it is common for infants to lose about three to seven percent of their birth weight within the first week, this reduction from 3250 grams at birth to 2990 grams upon discharge, and then increasing to 3080 grams during the next visit, falls within normal expectations. Since the infant is nursing well, this indicates that the breastfeeding is likely successful, and with the noted weight gain after initial loss, there is no immediate indication for concern. Instead of suggesting formula supplementation or a pediatric consultation, monitoring the weight is the key component here. A healthy neonate should start gaining weight at a rate of up to 20 grams per day after the first week. In the absence of other symptoms or concerns, additional interventions such as increasing breastfeeding frequency or high-calorie formula are not warranted at this stage.