RESEARCH A randomized longitudina e c

Full list of author information is available at the end of the articleBackground Human pregnancy involves large physiological changes, including increases in plasma volume and extracellular fluids and production of amniotic fluid, growth of fetus, mammary glands, uterus and placenta, and deposition of fat mass (FM). Thus, both FM and fat-free mass (FFM) increase. Although a healthy gestational weight gain (GWG) is needed to meet the needs of the fetus and the neonate, excessive increases in maternal weight are det-rimental for both mother and child. According to a model in one study, GWG in well-nourished women is 13.8 kg, including 4.3 kg of fat deposition [1]. However, GWG shows large interindividual variation, and average GWG is lower at higher body mass index (BMI) [2,3]. Reaching optimal GWG is complex, taking into account the health of both mother and child. New GWG recom-mendations were proposed in 2009 [4], in which a weight gain of 11–16 kg was recommended for normal weigh