ResearchPad - population-study-article Default RSS Feed en-us © 2020 Newgen KnowledgeWorks <![CDATA[Maternal serum levels of perfluoroalkyl substances in early pregnancy and offspring birth weight]]> Perfluoroalkyl substances (PFASs) are widespread, bioaccumulating, and persistent and show placental transfer. Emerging research indicates associations between prenatal exposure and low birth weight. The aim of this study was to assess the associations between first trimester exposure to PFASs and birth weight (BW) in the Swedish Environmental, Longitudinal, Mother and child, Asthma and allergy (SELMA) study and examine whether associations differ between girls and boys.MethodsEight PFASs were analyzed in maternal serum (median: 10 weeks of pregnancy). Associations between prenatal PFAS exposure and birth outcomes with BW, BW for gestational age, and birth small for gestational age (SGA) were assessed in 1533 infants, adjusted for potential confounders and stratified by sex.ResultsIncreased maternal perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), and perfluoroundecanoic acid (PFUnDA) were associated with lower BW, lower BW for gestational age, and SGA birth. Associations were significant only in girls, where prenatal exposure in the upper quartile was associated with a 93–142-g lower BW when compared with that of the lowest quartile exposure. The associations were not mediated by effects on gestational age.ConclusionsWe found associations between prenatal exposure for five different PFASs and birth weight, with more pronounced associations in girls than in boys. ]]> <![CDATA[Higher fat mass and fat mass accretion during the first six months of life in exclusively breastfed infants]]>


Early nutrition influences infant growth and body composition, which may play a role in the infant’s metabolic programming. Breastfed infants appear to have higher fat mass than formula-fed infants, but most comparisons have been cross-sectional, and evidence is scarce. The aim of this study was to describe fat mass and fat mass accretion during the first six months of life and evaluate differences by type of feeding (OMS).


Prospective cohort of healthy pregnant women and their infants (Mexico City, 2009–2014). At 1 (T1), 3 (T2) and 6 (T3) months of age, fat mass (FM) (PEAPOD) and type of feeding (feeding questionnaire) were evaluated.


We included 109 healthy infants (mean ± SD age: 39 ± 1.1 weeks; birthweight: 2959 ± 294 g). Exclusive/predominant breastfed (EBF) infants had higher FM at T2 and T3 compared with non-EBF (%FM T3: 29.7 ± 5.9% vs 24.7 ± 5.6%, respectively) (p < 0.05). All infants increased their FM throughout time (p < 0.001). EBF infants showed a significant higher FM accretion (β: 3.61; 95% CI: 1.57–5.66, p < 0.01); the difference was maintained after controlling for confounding variables.


Exclusive/predominant breastfeeding promotes higher accretion of FM during the first six months of life which could have an important effect in the programming of health outcomes later in life.