Extra weight during pregnancy linked to earlier onset of puberty in girls

Mothers who are overweight or have high blood glucose levels during pregnancy are more likely to give birth to girls who experience puberty early, a study has suggested.
Research examining the outcomes of over 15,000 girls and their mums linked the earlier onset of puberty in youngsters aged between 6-11 years to maternal obesity and hyperglycemia.
Girls who enter puberty at an early age have a greater risk of obesity and type 2 diabetes because the body can become more resistant to insulin. This study therefore highlights the importance of good weight management in pregnant women.
Pregnant women can maintain normal weight by eating a healthy diet low in sugar and getting exercise, which also helps to reduce a woman’s risk of developing gestational diabetes.
According to the Kaiser Permanente findings, mothers who were obese, categorised as having a Body Mass Index (BMI) of 30 and above, had a 40% greater risk of giving birth to a daughter who had earlier breast development. The study also found that expectant mums who were overweight, with a BMI between 25 and 30, had a 20% risk of this outcome.
The researchers concluded that there was a difference of seven months in the development of breasts earlier in girls from obese mums compared to overweight mothers.
This pattern was similar when it came to pubic hair development, but different ethnicities provided differing outcomes. For example, there was a 50% increased chance of earlier development in Asian girls from obese mothers compared to those who came from mums with a regular waistline, but this association was not recognised in African-American girls.
Women with high blood sugar levels during pregnancy were linked to giving birth to girls with earlier breast development, but this association was not observed in expectant mums who had gestational diabetes.
Explaining the findings, Dr Ai Kubo, research scientist with the Kaiser Permanente Northern California Division of Research, said: “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.”
The findings appear online in the American Journal of Epidemiology.