In a study of more than 15,000 girls and their mothers — all Kaiser
Permanente members in Northern California — maternal overweight and
hyperglycemia were linked to the earlier onset of puberty in girls 6 to
11 years old. Early puberty has been linked to multiple adverse health
developments as girls grow up.
The study, “Associations between maternal obesity and pregnancy
hyperglycemia and timing of pubertal onset in adolescent girls: A
population-based study,” was published today in American Journal of Epidemiology. The girls in the study were from diverse cultures and ethnicities.
Lead author Ai Kubo, PhD, MPH, Kaiser Permanente research scientist
“We know that maternal weight can influence childhood weight. What we are learning is that the in utero
environment may also affect the timing of future pubertal development
in offspring, which makes sense since human brains are developed in utero and the brain releases hormones affecting puberty,” said lead author Ai Kubo, MPH, PhD, research scientist with the Kaiser Permanente Northern California Division of Research.
This research builds on previous Kaiser Permanente research that demonstrated earlier onset of puberty in American girls, as well as the possible role of environmental, perinatal
and other risk factors. Early puberty, including the early onset of
breast development or menarche (initiation of menstruation), increases
the risk of adverse health outcomes including obesity, type 2 diabetes,
polycystic ovarian syndrome, and cancer in adolescence and adulthood.
For girls, it has been linked to a higher risk of adverse emotional and
behavioral outcomes including depression, anxiety, earlier sexual
initiation and pregnancy.
In 2010, Kaiser Permanente pediatricians in Northern California began
routinely documenting Tanner stages, a standardized measure of pubertal
development, in electronic health records during routine pediatric
exams. This study is the largest to link the Tanner-stage measurements
of girls with the medical records of their mothers in order to assess
the role of pregnancy-related factors on pubertal timing.
Researchers found that maternal obesity (body mass index of 30 or
more) and overweight (body mass index between 25 and 30) in mothers was
associated with 40 percent and 20 percent greater chance of earlier
breast development in girls, respectively. The study also found a
7-month difference in the onset of breast development in daughters of
obese versus underweight mothers.
For pubic hair development, similar associations between maternal
obesity and earlier onset were found. However, the data suggest that the
associations may differ by race and ethnicity. For instance, Asian
girls with obese mothers were 50 percent more likely to experience
earlier onset of pubic hair than Asian girls with normal-weight mothers,
while there were no associations among African-American girls.
The study also found a significant relationship between hyperglycemia
(elevated blood sugar during pregnancy) in mothers and the earlier
onset of breast development, but not in mothers with gestational
diabetes.
“It’s possible that women with the diagnosis of gestational diabetes
were more careful about weight and diet, which might have changed the
amount of weight gain and offspring development patterns, but other
studies need to replicate the finding to be able to conclude that there
is an association,” Kubo noted.
Senior author Larry Kushi, ScD, Kaiser Permanente research scientist
Senior author Lawrence H. Kushi, ScD,
research scientist with the Division of Research, said the study
provides new avenues for slowing the trend toward earlier sexual
maturation in girls. “Understanding the intergenerational effects of in utero
exposures is helping health care systems such as Kaiser Permanente to
develop new strategies for assisting women to manage weight and
hyperglycemia before and during pregnancy, not only for their own
health, but also for that of their children.”
Kaiser Permanente, the nation’s largest integrated health system, is
uniquely positioned to conduct research over the life course because its
members stay with the health system for many years. This stable
membership — in conjunction with comprehensive electronic medical
records — enables studies such as this one, in which the long-term
effects of exposures during pregnancy can be examined. For example,
previous studies have examined the relationships between breastfeeding and the risk of breast cancer recurrence; maternal obesity, gestational diabetes and the early onset of puberty; and the early onset of puberty and obesity in girls.
This study was funded by the National Institutes of Health.
In addition to Kubo and Kushi, co-authors were Cecile A. Laurent, MS, Assiamira Ferrara, MD, PhD, and Charles P. Quesenberry, PhD, Kaiser Permanente Northern California Division of Research; Juliana Deardorff, PhD, University of California, Berkeley School of Public Health; and Louise C. Greenspan, MD, Kaiser Permanente San Francisco Medical Center.
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About the Kaiser Permanente Division of Research
The Kaiser Permanente Northern California Division of Research
conducts, publishes and disseminates epidemiologic and health services
research to improve the health and medical care of Kaiser Permanente
members and society at large. It seeks to understand the determinants of
illness and well-being, and to improve the quality and
cost-effectiveness of health care. Currently, DOR’s 600-plus staff is
working on more than 350 epidemiological and health services research
projects. For more information, visit divisionofresearch.kaiserpermanente.org or follow us @KPDOR.
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 more than 12 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
Permanente Medical Group 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.
For more information, contact: Janet Byron, janet.l.byron@kp.org, 510-891-3115
