Literature review for - Flourish Paediatrics

Notes on postpartum weight loss
Ip summarises the issue in the following way (Ip, Chung et al. 2007)
“ Despite the fact that the average weight retention associated with child bearing is modest,
estimated at approximately 1.51 kg (s.d.=5.95 kg) for some, there is some risk of major
weight gain with pregnancy. Ohlin and Rossner 1990 reported changes in body weight that
ranged from –12.3 to +26.5 kg from preconception to 1 year postpartum. In various studies,
the proportion of women retaining 5 kg or more after 6 months postpartum ranged from 14 to
20%. Studies of the impact of physiological and behavioral influences, such as dietary
intake, physical activity, and lactation on postpartum weight change reported mixed results.
Studies of postpartum weight changes in lactating and non-lactating women also were
equivocal within and across populations, with some showing that the length and intensity of
breastfeeding were associated with less weight retention after pregnancy, while other studies
reported that women who fed their infants formula lost more weight than women who nursed
their infants.
Commonly considered confounders in the relationship between return to pre-pregnancy
weight or post-partum weight change and breastfeeding were pre-pregnancy weight or BMI,
age, educational level, physical activity, parity, smoking status, dieting practice, and
ethnicity.”
They then concluded:
“Based on the results from three prospective cohort studies, we concluded that the overall
effect of breastfeeding on return-to-pre-pregnancy weight (weight change from prepregnancy
or first trimester to 1 to 2 year postpartum) was negligible (less than 1 kg). Results from four
prospective cohort studies showed that the effects of breastfeeding on postpartum weight loss
were unclear. All seven studies consistently suggested that many other factors have larger
effects on weight retention or postpartum weight loss than breastfeeding. Examples of which
included annual household income, baseline BMI, ethnicity, gestational weight gain, and
energy intake. Undoubtedly, all these factors need to be carefully considered in any future
investigation of the relationship between breastfeeding and postpartum weight changes.”
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