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School of Public Health




Background: There is a peculiar phenomenon: two separate individuals (mother and foetus) have a mutually interactive dependency concerning their respective weight. Very thin mothers have a higher risk of small for gestational age (SGA) infants, and rarely give birth to a large for gestational age (LGA) infant. While morbidly obese women often give birth to LGA infants, and rarely to SGA. Normal birthweight (AGA) infants (>10th and investigate the interaction between maternal booking BMI, gestational weight gain (GWG) and neonatal birthweight centiles. Methods: 16.5 year-observational cohort study (2001e2017). The study population consisted of all consecutive singleton term (37 weeks onward) live births delivered at University’s maternity in Reunion island, French Overseas Department. Findings: Of the 59,717 singleton term live births, we could define the booking BMI and the GWG in 52,092 parturients (87.2%). We had 2 major findings (1) Only women with a normal BMI achieve an equilibrium in the SGA/LGA risk (both 10%). We propose to call this crossing point the Maternal Fetal Corpulence Symbiosis (MFCS). (2) This MFCS shifts with increasing GWG. We tested the MFCS by 5 kg/m2 incremental BMI categories. The result is a linear law: opGWG (kg) ¼ 1.2 ppBMI (Kg/m2 ) þ 42 2 kg Interpretation: IOM-2009 recommendations are adequate for normal and overweighted women but not for thin and obese women: a thin woman (17 kg/m2 ) should gain 21.6 2 kg (instead of 12.5e18). An obese 32 kg/m2 should gain 3.6 kg (instead of 5e9). Very obese 40 kg/m2 should lose 6 kg

Source Citation

Robillard P-Y, Dekker G, Boukerrou M, Le Moullec N, Hulsey TC. Relationship between pre-pregnancy maternal BMI and optimal weight gain in singleton pregnancies. Heliyon. 2018;4(5):e00615. doi:10.1016/j.heliyon.2018.e00615