What would the nurse use as the basis for the teaching plan when caring for a pregnant teenager concerned about gaining too much weight during pregnancy?

A total gain of 25 to 30 pounds.

To ensure adequate fetal growth and development during the 40 weeks of a pregnancy, a total weight gain 25 to 30 pounds is recommended: 1.5 pounds in the first 10 weeks; 9 pounds by 30 weeks; and 27.5 pounds by 40 weeks. The pregnant woman should gain less weight in the first and second trimester than in the third. During the first trimester, the client should only gain 1.5 pounds in the first 10 weeks, not 1 pound per week. Aweight gain of pound per week would be 20 pounds for the total pregnancy, less than the recommended amount.