Welcome to period.com - Information on Pregnancy Ovulation Calendar

Following menarche, adiposity increases, particularly in the viscera and at subcutaneous sites on the trunk. Because the adipose tissue stored at these sites is an important determinant of insulin resistance, adolescents who conceive soon after menarche might start pregnancy with smaller adipose tissue stores and therefore be less insulin resistant than older women who are the same size. Maternal insulin resistance is one factor that affects the relationship between fetal and maternal weight gain. Therefore, a low percentage of maternal central body fat could impair fetal growth by creating a metabolic environment that favors maternal over fetal fat deposition.

Two techniques used to measure body fat distribution are computed tomography (CT) and magnetic resonance imaging (MRI). However, they use radiation and strong magnetic fields, which are prohibited during pregnancy. Ultrasound is safe during pregnancy, portable, and noninvasive, and has been shown to be highly correlated to CT-derived measures of visceral adiposity. To develop a reliable technique for studying the effect of fat distribution in the body on insulin resistance, some researchers from Denver, Colorado compared the value of skinfold caliper and ultrasound measurements on the distribution of subcutaneous adipose tissue and ultrasound measurements of visceral adiposity (US-VAT) for insulin resistance in pregnant adolescents.

In an adolescent maternity program 16 girls, aged 13 to 19 who enrolled before the 14th week of gestation were included in this study. There were two study visits: One at enrollment and a second visit early in the third trimester. The fasting insulin and glucose-to-insulin ration were used to quantify insulin resistance. The distribution of subcutaneous adipose tissue was measured first by using a skinfold caliber at three sites on the extremities (triceps, biceps, and thighs) and three on the trunk (subscapular, costal, and suprailiac) and ten by two experienced songoraphers.

The girls gained weight at a rate of 0.5 kg/week during gestation and the study period and gave birth at 38 weeks gestation. Fasting insulin levels and glucose-to-insulin ratios increased significantly during the study period. At the second study visit, fasting insulin level and glucose-to-insulin ratio was significantly correlated with the rate of weight gain. Thus, during this visit, insulin resistance was significantly related to total, visceral, and subcutaneous fat. The skinfold caliper measurement of subcutaneous fat at the subscapular site and the US measurement of subcutaneous fat at the costal site were the best predictors of insulin resistance. BMI was not associated to either model of adiposity.

Skinfold caliper determinations of the subscapular skinfold thickness and ultrasonic determinations of the costal skinfold thickness are better predictors of maternal insulin resistance than body mass index (BMI). Collectively, these data indicate that most of the adipose tissue retained during pregnancy is stored subcutaneously on the mink and that maternal visceral adiposity increases minimally during gestation.'

Catherine Stevens-Simon, Patti Thureen, Joan Barrett, and Elizabeth Stamm, Regional Body, Fat Distribution and Insulin Resistance During Adolescent Pregnancy JADA 102(4): 563-565 (April 2002) Correspondence: Catherine Stevens-Simon. MD, Department of Pediatrics--Division of Adolescent Medicine, University of Colorado Health Science Center--The Children's Hospital, 1056 E 19th St, Denver, CO 80218