The measurement of energy expenditure in women pregnant with twins or triplets using indirect calorimetry

Abstract

The purpose of this study was to compare the resting energy needs of women who are pregnant with multiple fetuses with protocol recommended caloric intakes. Participant's resting energy needs were measured using indirect calorimetry. A 24 hour dietary recall, an upper arm circumference, a pre-pregnancy BMI, and a weight gain chart were done as well. These data were compared to the outcomes of the twin and triplet pregnancies of the participants. Participants were recruited from the practice of Dr. Bannie Tabor, MD. There were five women who participated in this study ranging in age from 29-36. Two were pregnant with twins and three with triplets. All were fertility driven pregnancies except one of the triplet pregnancies. Procedures included an initi al questionnaire giving number of fetuses, the due date, weeks of gestation, their prepregnancy weight, their current weight, height, whether this was a first pregnancy, their birthdate, activity level, any health issues, and any supplements. It also included a 24 hour dietary recal l. Each time a participant was seen for this study, this information was updated, upper arm measurement was done, a prenatal weight gai n chart was maintained, and REE was measured using a Metabolic Cart. Results of this study did not reflect any valid differences in REE between twin and triplet moms. It did show that the REE was substanti al ly lower in the third trimester than the second even when kcals were high. The real value to outcomes however, was seen in the tracking of their weight gain and caloric intake. Each participant's weight was tracked against ideal weight gain for twin or triplet pregnancies for optimum outcome. When there was a consistant weight gain and caloric intake c losely reflecting recommendations, the outcomes of the pregnancies were positive. When a participant had difficulty in gaining weight, the lengths of gestation and outcomes were far less successful. Currently, accepted protocol for a multiple fetus pregnancy is to track the fetuses through sonogram measurements as a determination for pregnancy development. with little emphasis on maternal weight gain or caloric intake. This study illustrated the need for a much larger and longer study to determine if growth of the pregnant woman herself should be followed more closely and become a valid protocol tool for assisting pregnancy outcomes, especially in multiple fetus pregnancies.