Houston, Texas, USA : If a mother smokes during pregnancy, there is a risk of her children starting puberty earlier. This is shown by a major study from Aarhus University, which has just been published in the international journal American Journal of Epidemiology.
“We found that children of mothers who had smoked more than 10 cigarettes a day during pregnancy, on average entered puberty three to six months earlier than the children of non-smokers,” says Ph.D. student Nis Brix, who is one of the researchers behind the study.
The study is one of the largest puberty studies worldwide, and the results are based on the survey “Better health for generations” from the Statens Serum Institut in Denmark.
May lead to diseases later
A total of 15,819 pregnant women and their children participated in the study. During pregnancy, the women were asked about their smoking habits. Then, the children were followed and filled in 83,810 questionnaires about their pubertal development from the age of eleven and every six months thereafter.
The researchers find early puberty worrisome.
“Early puberty can be associated with an increased risk of a number of diseases as an adult, such as obesity, diabetes, cardiovascular diseases and certain types of cancer,” says Nis Brix. Together with his colleagues, he is working to identify the causes of puberty to be able to prevent it occurring.
“It is known that smoking is harmful to the unborn foetus. Smoking is, among other things, associated with an increased risk of low birth weight, premature birth and increased mortality. There are thus a wide range of other good reasons to give up smoking before pregnancy. We hope that our results can be used as another motivating factor to stop smoking among women who are planning on becoming pregnant,” says Nis Brix.
Citation : Nis Brix et al, Maternal Smoking During Pregnancy and Timing of Puberty in Sons and Daughters: A Population-Based Cohort Study, American Journal of Epidemiology. DOI: 10.1093/aje/kwy206
A separate study found that painkillers during pregnancy lead to early puberty in girls.
Painkillers During Pregnancy Lead To Early Puberty In Girls
The more weeks a woman takes pain-reliving medication during pregnancy, the earlier their daughters enter puberty. This is shown by a new study from Aarhus University.
For the majority of girls, puberty begins when they are around 10 or 11 years old. Puberty onset can be earlier if the mother has taken painkillers containing paracetamol during pregnancy. Researchers from Aarhus University examined the correlation between the intake of the analgesic paracetamol during pregnancy and pubertal development in boys and girls. The results have just been published in the American Journal of Epidemiology.
“We found a dose-response correlation. That is to say, the more weeks with paracetamol during pregnancy, the earlier puberty in girls, but not in boys,” says Ph.D. student Andreas Ernst from the Department of Public Health, Aarhus University, who is behind the study.
The study is based on the largest collection of puberty data in the Danish birth cohort (BSIG.dk). A group of around 100,000 women provided detailed information about their use of paracetamol three times during their pregnancy. A total of 15,822 children, 7,697 boys and 8,125 girls born to these mothers between 2000 to 2003 were followed from the age of 11 and throughout puberty with questionnaires every six months about several different aspects of their development.
The study showed that girls on average enter puberty between 1.5 and three months earlier if the mother took painkillers for more than 12 weeks during pregnancy.
“While entering puberty 1.5 to three months earlier may seem unimportant, when taken together with the frequent use of paracetamol during pregnancy, our findings ought to make people take notice. Our results are certainly not the decisive factor that should change current practice, but the perception of paracetamol as a safe and harmless choice during pregnancy ought to be challenged,” explains Andreas Ernst.
Worldwide, the average consumption of paracetamol has been increasing, and studies suggest that more than 50 percent of pregnant women make use of painkillers containing paracetamol at least once during their pregnancy. “As earlier pubertal development has previously been tied to an increased risk of more frequent and serious diseases in adulthood such as obesity, diabetes, cardiovascular diseases and testicular and breast cancer, it’s important to identify possible causes of early puberty so we can prevent this development,” says Andreas Ernst.
Citation for second study: Andreas Ernst et al, Acetaminophen (Paracetamol) Exposure During Pregnancy and Pubertal Development in Boys and Girls From a Nationwide Puberty Cohort, American Journal of Epidemiology. DOI: 10.1093/aje/kwy193