Adolescent boys whose mothers were younger at menarche are at increased risk for obesity vs. sons of mothers with older menarche, according to findings published in Clinical Endocrinology.
“A number of studies have shown that girls who enter menarche earlier are more likely to develop obesity, diabetes, hypertension and metabolic syndrome,” José Derraik, PhD, a senior research fellow at the Liggins Institute at the University of Auckland, New Zealand, and honorary associate professor at the Children’s Hospital of Zhejiang University School of Medicine, China, told Endocrine Today. “In our study, we also observed an association between earlier menarche and increased markers of adiposity in Chinese girls. Importantly, we showed that the potential adverse effects of earlier menarche seem to extend into the next generation. The sons of mothers who experienced earlier menarche were three times more likely to develop obesity. Interestingly, however, we did not detect adverse associations among the daughters.”
Derraik and colleagues analyzed data from 304 girls and 190 boys aged 11 to 16 years who attended local primary schools and high schools in Zhejiang province, China, in 2009 and 2010 (mean age, 14 years). Clinical research nurses examined the children at their respective schools, assessing BMI and waist circumference and collecting fasting blood samples. Maternal and paternal height and weight and the menarche age of mothers and daughters were obtained via self-report from questionnaires completed at home. Researchers used linear regression analyses to assess associations between maternal age at menarche as a continuous variable and offspring outcomes.
Researchers found that the average age at menarche was 2.4 years younger in daughters vs. mothers (mean, 12 years vs. 14.4 years; P < .0001). Maternal age at menarche was not associated with anthropometry or metabolism in daughters; however, among boys, increasing maternal age at menarche was correlated with lower height standard deviation score (SDS), lower height SDS adjusted for parents’ height, BMI SDS and waist and hip circumference, as well as lower odds for obesity (OR = 0.75; 95% CI, 0.56-0.99).
Boys whose mothers were aged 13 years or younger at menarche were three times as likely to have obesity vs. boys whose mothers were older at menarche (adjusted RR = 2.96; 95% CI, 1.49-5.87).
Researchers also observed that daughters’ age at menarche was correlated with a higher BMI SDS (P < .0001), whereas increasing age at menarche in daughters was associated with lower waist circumference, hip circumference and waist-to-height ratio. In stratified analyses, girls in the youngest menarcheal age tertile (menarche age, 8.8 to 11.6 years) had a diastolic blood pressure that was, on average, 2.2 mm Hg higher vs. girls in other tertiles (P = .029).
“Although it is still uncertain whether earlier menarche leads to greater adiposity or vice versa, there is increasing evidence that childhood obesity may be an important driver of earlier pubertal onset,” Derraik said. “Therefore, there is some suggestion that the prevention of childhood obesity may be the best strategy to halt the ongoing trend toward earlier menarche.”
Derraik said it is important to understand the mechanisms underpinning earlier menarche, which would require longitudinal studies involving large birth cohorts with regular clinical follow-up of participants throughout childhood and adolescence.
“In addition, while there is considerable evidence that males and females are differentially affected by environmental stressors during gestation and early life, the exact mechanisms are still poorly understood,” Derraik said. “It is necessary to better understand the processes that occur during pregnancy that may adversely affect one sex over the other, as it was the case in our study.” – by Regina Schaffer
For more information:
José Derraik, PhD, can be reached at the Liggins Institute, University of Auckland, Private Bag 92019, Auckland, New Zealand; email: email@example.com.
Disclosures: The authors report no relevant financial disclosures.