The storm of puberty hits children much earlier today than it did decades ago. During the pandemic, the number of people experiencing premature puberty rose significantly again. Why this is is unclear.
Doctors have been reporting on puberty starting earlier and earlier on average for several decades. The corona pandemic has significantly increased this effect. “20 to 30 percent more cases of premature puberty were recorded,” says Bettina Gohlke from the Bonn University Children’s Hospital. The phenomenon has been noticed worldwide; there is corresponding data from Europe as well as from the USA and China.
Precocious puberty – called pubertas praecox – is the development of external sexual characteristics in boys before the age of 9 and in girls before the age of 8. Among other things, the girls’ breasts then develop – one assumption about the Corona effect was that parents were more likely to notice the earlier development because they spent more time with their children due to school closures and home offices.
Possible causes for the increase
A connection with higher psychosocial stress is also possible, explains pediatric endocrinologist Gohlke. Previous studies have shown that children in such situations mature physically earlier. A weight effect is also being discussed: Many children ate more or exercised noticeably less during the pandemic – and obesity is considered one of the most important factors for early puberty.
“But even when weight was taken out, there was still an increase in cases of prepuberty,” says Gohlke. “It is probably a multifactorial effect.” It is still unclear whether it will evaporate once the pandemic subsides.
Biological basis of puberty
Biologically, puberty begins with the increased production of sex hormones, as Munich endocrinologist Günter Stalla explains. In boys, the testicles and scrotum enlarge, followed by an elongation of the penis. Pubic and armpit hair grows. In girls, the breasts develop, shortly afterwards pubic and armpit hair begins to grow, and years later the first menstrual period follows.
According to data from a research team led by Gohlke, the average age at onset of puberty in girls has fallen by about three months per decade since the 1970s. The development is similar for boys. The age at the end of puberty, however, has not changed in the past 50 years – so puberty lasts longer on average than before. The average age at the first menstrual period has also hardly changed.
Influences on the onset of puberty
In principle, it is primarily genetically determined when the hormone release and thus the puberty machinery starts, explains Hamburg endocrinologist Stephan Petersenn. Factors such as persistent psychological stress and diet also have an influence. Overweight is considered to be a key factor in the development of the past few decades: the messenger substance leptin, which promotes puberty, is increasingly produced in the fatty tissue, says Petersenn, media spokesman for the German Society for Endocrinology (DGE). The fatter a child, the earlier it develops into an adult.
The onset of puberty is always related to the standard of living in society, says Petersenn. It is easy to imagine that there have been significant fluctuations in the starting age in the past. Currently, premature puberty affects children from socially disadvantaged families more often because they are more often overweight, says Stalla, former president of the German Society for Endocrinology. “Health depends on social status and education, and that is also evident here.”
“The problem is the lack of studies”
Many experts believe that in addition to being overweight, children today are exposed to a whole cocktail of hormonal substances. “It is very likely that this will have an influence,” emphasizes Gohlke. Stalla and Petersenn also see clear signs of this. “The problem is the lack of studies,” explains Gohlke. Only limited conclusions can be drawn from animal experiments; clinical studies on humans are not possible in this area.
What does early puberty mean for a child according to current medical guidelines? “The onset of puberty is a growth accelerator,” explains Stalla. Children who puberty early initially shoot up faster – but there is an opposite process in their case, which means that they ultimately remain smaller on average than those who start puberty later. The sex hormones that initially accelerate growth also cause it to end prematurely by closing the growth plates.
Ways to delay puberty
In addition to such physical consequences, there can be psychological ones, as Petersenn says. And not just because children are ashamed of breast growth or hair, for example: with the onset of puberty, the way they think and their emotional world also changes, which can lead to problems among friends, explains Petersenn. “You mature into adult thinking earlier.”
Possible long-term consequences such as a higher risk of certain diseases are also being discussed among experts – but there is a lack of reliable information. “There is no really good data on long-term consequences,” says Gohlke.
The premature start of puberty can be stopped by injecting synthetic messenger substances that stop the production of sex hormones every three months. In Gohlke’s experience, in girls who start puberty at the age of seven to seven and a half, the child or their parents decide against such therapy in around half of the cases. However, some parents or even the child themselves find the diagnosis very stressful.
The doctor explains that therapy no longer plays a role in height growth. To do this, it has to start earlier, before the age of six. But such cases are rare.