Predictors of longitudinal changes in body composition and BMI in Brazilian lactating women during the first 8·5

Adriana Divina de Souza Campos1, Gabriela Torres Silva1, Ana Lorena Lima Ferreira1,2

  • 1Nutritional Epidemiology Observatory, Josué de Castro Nutrition Institute, Rio de Janeiro Federal University, Rio de Janeiro, Brazil.

Pregnancy and lactation change women's body composition (BC), but few longitudinal studies have investigated postpartum BC trajectories. We aimed to investigate maternal and infant predictors of maternal body fat (BF), fat mass (FM), fat-free mass (FFM) and BMI trajectories during lactation. Longitudinal study with 234 Brazilian mother-infant dyads followed at 1·0-3·49, 3·5-5·99 and 6·0-8·5 months postpartum. Maternal BC was estimated using bioelectrical impedance at all follow-up points. Longitudinal mixed-effects models with interaction terms with time (weeks postpartum) were employed. FFM declined significantly over weeks postpartum (β = -0·02 kg; 95 % CI -0·03, -0·01). Pre-pregnancy overweight women experienced an increase in all body components (BF: β = 4·91 %, 95 % CI 3·79, 6·04; FM: β = 6·46 kg, 95 % CI 5·26, 7·67; FFM: β = 3·72 kg, 95 % CI 2·80, 4·65) and BMI (β = 4·51 kg/m2, 95 % CI 3·91, 5·12). Multiparous women showed BMI increases (β = 0·76 kg/m2, 95 % CI 0·11, 1·41), and those who delivered by caesarean had FFM (β = 1·87 kg, 95 % CI 0·67, 3·07) and BMI (β = 1·39 kg/m2, 95 % CI 0·61, 2·18) increases. Women who birthed girls had reductions in FM (β = -1·24 kg, 95 % CI -2·41, -0·07) and FFM (β = -0·93 kg, 95 % CI -1·84, -0·01). Interactions occurred between maternal age ≥ 30 years, higher family income, multiparity and infant sex for BC and BMI trajectories. Maternal age, pre-pregnancy BMI, parity, family income, mode of delivery and infant sex predict maternal BC and BMI trajectories.

Related Concept Videos

Longitudinal Research02:20

Longitudinal Research

Sometimes we want to see how people change over time, as in studies of human development and lifespan. When we test the same group of individuals repeatedly over an extended period of time, we are conducting longitudinal research. Longitudinal research is a research design in which data-gathering is administered repeatedly over an extended period of time. For example, we may survey a group of individuals about their dietary habits at age 20, retest them a decade later at age 30, and then again...
11.8K
Longitudinal Studies01:26

Longitudinal Studies

Longitudinal studies are also widely used in other medical and social science fields. For instance, in cardiovascular research, they can monitor patients' health over decades to identify risk factors for heart disease, such as high cholesterol or smoking, and evaluate the long-term effectiveness of preventive measures. Similarly, in mental health studies, researchers might follow individuals from adolescence into adulthood to understand the development and progression of conditions like...
101
Regression Toward the Mean01:52

Regression Toward the Mean

Regression toward the mean (“RTM”) is a phenomenon in which extremely high or low values—for example, and individual’s blood pressure at a particular moment—appear closer to a group’s average upon remeasuring. Although this statistical peculiarity is the result of random error and chance, it has been problematic across various medical, scientific, financial and psychological applications. In particular, RTM, if not taken into account, can interfere when...
6.3K
Anatomy of the Intestines01:23

Anatomy of the Intestines

Although digestion of proteins, carbohydrates, and lipids may begin in the stomach, it is completed in the intestine. The absorption of nutrients, water, and electrolytes from food and drink also occurs in the intestine. The intestines can be divided into two structurally distinct organs—the small and large intestines.
Small Intestines
The small intestine is an ~7 meter-long tube with an inner diameter of just 2.5 cm. Since most nutrients are absorbed here, the inner lining of the...
71.0K
Obesity01:24

Obesity

The Body Mass Index (BMI) is a numerical value derived from a person's weight and height, used to categorize individuals into weight ranges. It is calculated using the formula: weight in kilograms divided by height in meters squared. Obesity is a health condition characterized by excessive accumulation of adipose tissue that poses health risks, often diagnosed with a BMI ≥ 30. This excess fat storage occurs when surplus dietary calories are converted into triglycerides and stored in...
350