RESUMO
This investigation describes the pattern of changes in mid-upper arm circumference (MUAC), triceps, biceps and subscapular skinfold thicknesses during the course of pregnancy, and its relationship with maternal and newborn outcomes. A prospective cohort of 1066 pregnant women were selected in seven different urban regions in Argentina. Measurements of MUAC were carried out at 16, 28 and 36 gestational weeks. In a subsample of 488 women, triceps, biceps and subscapular skinfold thicknesses were measured. Mean total increase in subscapular, tricipital and bicipital skinfolds from 16 to 36 weeks of gestation were 4.5, 3.6 and 2.6 mm, respectively. MUAC showed a mean increase of 1.7 cm in the same period. Overweight or obese women at the start of pregnancy had lower increases in all measurements compared with women with normal or low body mass index. Maternal anthropometry was related to birthweight; women who gave birth to infants of less than 3000 g had lower average values in all measurements than those who had normal birthweight infants. LMS curves for MUAC and skinfolds by gestational age are presented, which can be used as a reference to assess maternal nutrition status during pregnancy. MUAC, tricipital and subscapular skinfold for gestational age curves are proposed for monitoring maternal nutritional status during pregnancy. MUAC cut-off points of 24.5, 25.5 and 26.5 cm for 16, 28 and 36 weeks of gestation, respectively, are also proposed as a proxy to detect low birthweight.