Methods of adiposity measurement
| Adiposity measure | Measurement |
| Subcutaneous adipose tissue* | Midline transverse section of the maternal abdomen, approximately 1 cm above the umbilicus from outer border of the subcutaneous fat layer to the outer border of rectus abdominus at the level of linea alba |
| Visceral adipose tissue* | Midline transverse section of the maternal abdomen, approximately 1 cm above the umbilicus from the inner border of rectus abdominus at the level of linea alba to the anterior wall of the aorta |
| Preperitoneal subcutaneous adipose tissue* | Sagittal plane of xiphisternum from the lower border of the cutaneous layer to the upper border of the linea alba |
| Preperitoneal visceral adipose tissue* | Sagittal plane of xiphisternum from the lower border of linea alba to the upper border of the liver capsule |
| Waist circumference† | Narrowest point of the abdomen between the lower costal (10th rib) border and the top of the iliac crest, perpendicular to the long axis of the trunk, at the end of normal expiration and with the abdominal muscles relaxed, to the nearest 0.1 cm |
| Hip circumference† | Greatest posterior protuberance of the buttocks, perpendicular to the long axis of the trunk, with the gluteal muscles relaxed and the feet together, over light clothing and to the nearest 0.1 cm |
| Height† | To the nearest 0.1 cm with shoes removed and the participant’s head positioned in the Frankfort plane |
| Weight† | In light clothing to the nearest 100 g |
| Neck circumference | Immediately superior to the thyroid cartilage and perpendicularly to the long axis of the neck with the head in the Frankfort plane, to the nearest 0.1 cm |
| Mid upper arm circumference | Midpoint of the upper arm between the acromiale and radiale, perpendicular to the long axis of the arm, to the nearest 0.1 cm |
| Skinfold thickness‡ | Subscapular, triceps, biceps, iliac crest and supraspinale measured using Harpenden skinfold callipers, to the nearest 0.1 mm |
*Total adipose tissue will be calculated as a sum of subcutaneous and visceral adipose tissue.
†Waist-to-hip ratio, waist-to-height ratio, BMI, Body Adiposity Index, A Body Shape Index (ABSI), Hip Index, Weight-Adjusted Waist Index, Body Roundness Index, Total abdominal fat, Abdominal Volume Index, Conicity Index, estimated total body fat, Relative fat Mass, Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE) and body fat percentage will be calculated from these measurements.
‡Sum of skinfolds will be calculated using five skinfold measurements.