Department of Research & Evaluation News

PASADENA, Calif. – A new Kaiser Permanente study, published in Pediatric Obesity, found that pre-pregnancy obesity and excessive weight gain during pregnancy was associated with an increased risk of the child becoming overweight at age 2. The study also found breastfeeding for at least six months helped reduce the likelihood of a child being overweight at age 2.

In the past 30 years, obesity has more than doubled in children and quadrupled in adolescents, with more than one-third of children and adolescents found to be overweight or obese in 2012, according to the Centers for Disease Control and Prevention.

Childhood obesity is linked with adult obesity and long-term negative health outcomes, which is why it is important to explore which factors may contribute to excessive weight during early childhood, explained the study’s lead author, Anny H. Xiang, PhD, of the Kaiser Permanente Southern California Department of Research & Evaluation. Our study findings highlight the need for more public health efforts to reduce maternal obesity, appropriate gestational weight gain and to promote breastfeeding.

Although previous studies have identified a link between maternal obesity and/or excessive gestational weight gain and long-term obesity risk in children, the Kaiser Permanente study included women and children who received standard medical care and it examined the interplay among all four factors associated with childhood obesity: pre-pregnancy obesity, gestational weight gain, gestational diabetes and breastfeeding. 

The research team found:

·         A woman being obese (BMI of 30.0 or higher) prior to getting pregnant increased the odds of her child being overweight at age 2 by more than two-fold compared to women who had a normal pre-pregnancy weight (BMI between 18.5 and 25), after adjusting for weight gain during pregnancy, gestational diabetes and breastfeeding.

·         A woman being overweight (BMI between 25.0 and 29.9) prior to pregnancy was associated with 50 percent increased odds of her child being overweight at age 2.

·         Excessive weight gain during pregnancy was associated with 23 percent increased odds of a child being overweight at age 2 compared to women who had healthy weight gain during pregnancy after adjusting for pre-pregnancy weight, gestational diabetes and breastfeeding.

·         Breastfeeding for at least six months was associated with a 24 percent reduction for the odds of a child being overweight at age 2 regardless of a mother’s pre-pregnancy weight, gestational diabetes or excessive weight gain during pregnancy.

The study included 15,710 women who delivered babies at Kaiser Permanente medical facilities in Southern California in 2011. Excessive weight gain was defined according to Institute of Medicine guidelines, with normal-weight women gaining more than 35 pounds, overweight women gaining more than 25 pounds and obese women gaining more than 20 pounds during their pregnancy. Children were considered overweight at age 2 if their BMI was greater than the 85th percentile for their age and sex, based on growth charts from the Centers for Disease Control and Prevention.

The study was supported by Kaiser Permanente Southern California Community Benefit funds.

Other authors of the study include Zoe Bider-Canfield, MPH, Mayra P. Martinez, MPH, Xinhui Wang, PhD, Wei Yu, MS, with the Kaiser Permanente Southern California Department of Research & Evaluation; May P. Bautista, MSN, with Kaiser Permanente Consulting & Implementation; John Brookey, MD, with Kaiser Permanente Quality and Risk; and Kathleen A. Page, MD, and Thomas A. Buchanan, MD, with the Department of Medicine and Diabetes and Obesity Research Institute, Keck School of Medicine of the University of Southern California.

 About the Kaiser Permanente Southern California Department of Research & Evaluation

The Department of Research & Evaluation conducts high-quality, innovative research into disease etiology, prevention, treatment and care delivery. Investigators conduct epidemiologic research, health services research, biostatistics research, and behavioral research as well as clinical trials. Major areas of study include chronic disease, infectious disease, cancer, drug safety and effectiveness, and maternal and child health. Headquartered in Pasadena, California, the department focuses on translating research to practice quickly to benefit the health and lives of Kaiser Permanente Southern California members and the general public. Visit kp.org/research.

About Kaiser Permanente

Kaiser Permanente is committed to helping shape the future of health care. We are recognized as one of America’s leading health care providers and not-for-profit health plans. Founded in 1945, Kaiser Permanente has a mission to provide high-quality, affordable health care services and to improve the health of our members and the communities we serve. We currently serve more than 10 million members in eight states and the District of Columbia. Care for members and patients is focused on their total health and guided by their personal physicians, specialists and team of caregivers. Our expert and caring medical teams are empowered and supported by industry-leading technology advances and tools for health promotion, disease prevention, state-of-the-art care delivery and world-class chronic disease management. Kaiser Permanente is dedicated to care innovations, clinical research, health education and the support of community health. For more information, go to: kp.org/share.