Postpartum Anthropometric and Body Composition

Anthropometric and BC measurements were performed for both mothers and infants at 3 months postpartum (3.1 ± 0.1 months; range: 2.9–3.5). Maternal weight was measured using Seca electronic scales (±0.1 kg; Seca, Chino, CA, USA). Height was self-reported by mothers or measured against a marked wall. Infant clothes were removed before measuring weight using electronic scales (Medela Inc.). Infant crown to heel length was measured in supine position with an infantometer (Seca, Chino, CA, USA). Infant head circumference was measured with non-stretch tape to the nearest 0.1 cm. Infant z-scores (WLZ), weight-for-age z-scores (WAZ), length-for-age z-scores (LAZ), BMIAZ and head circumference-for-age z-scores (HCAZ) were measured using the World Health Organization (WHO) Anthro software v3.2.2 [30 ].
Maternal and infant BC was measured with bioelectrical impedance spectroscopy using a battery-operated bioelectrical impedance analyser Impedimed SFB7 (ImpediMed, Brisbane, QLD, Australia) according to the protocols described previously by Gridneva et al. [31 (link)]. In addition to standard BC measurements (fat-free mass (FFM), FM, and %FM), the height-normalized BC indices of mothers and infants (FFMI, FMI) as well as FM to FFM ratio (FM/FFM) were calculated as described previously [6 (link)].