Pregnancy: Paracetamol, a pain reliever, can be used by boys later

How does it affect children if mothers take paracetamol during pregnancy?
Researchers have now found that the use of paracetamol during pregnancy can inhibit the development of male behavior in mice. The drug can reduce both sex drive and aggressive behavior.

The University of Copenhagen scientists found in their study that taking paracetamol during pregnancy can reduce so-called male behavior patterns. The doctors published the results of their study in the journal "Reproduction".

Paracetamol damages the development of male behavior
The drug paracetamol is particularly valued for its analgesic effect. However, pregnant women should think twice about using paracetamol. In an animal model, the drug caused the development of male behaviors to be suppressed, the study's authors say.

Paracetamol can cause testicular malformation
Previous studies have shown that acetaminophen can inhibit the development of the male sex hormone testosterone in fetuses. This increases the risk of testicular malformation in infants. But a reduced testosterone level in the fetal stage is also significant for the behavior of adult males, the scientists explain.

Changes could still be noticed in adulthood
A reduced testosterone level means that male characteristics do not develop as they should, the researchers say. When the test animals were exposed to paracetamol at the fetal stage, they could not copulate in the same way as the control group. The so-called male programming was not properly established during fetal development, which could also be observed in animals later in adulthood, the authors add in a press release.

Similar attempts on humans would be inappropriate
The dose administered to the mice was approximately the recommended dose for pregnant women. Because the experiments are limited to mice, the results cannot be directly transferred to humans, the doctors explain. Given the certainty of the harmful effects of paracetamol in pregnancy, however, similar human trials are inappropriate.

What male behaviors were affected?
Testosterone is the primary male sex hormone. It helps develop the male brain programming. The reduced masculine behavior in mice observed by the researchers was the aggressiveness towards other male mice, the ability to copulate and the tendency to territorial marking. The mice affected by acetaminophen reacted much more passively than normal in all three factors. They didn't attack other male mice, they had problems reproducing and behaved like female mice when it came to territorial labeling, the scientists say.

How does the lack of testosterone affect the brain?
After observing the changed behavior patterns, the researchers examined the specific effects of a lack of testosterone in the brain. The results were clear here too. The area of ​​the brain that controls the sex drive contained half as many neurons in the acetaminophen mice, the experts explain. Inhibition of testosterone also halved activity in an area of ​​the brain that is significant for male characteristics.

Effects on female mice
This study focused on the effects of acetaminophen on male properties. The use of paracetamol during pregnancy also influences the later life of female mice, the study authors explain. For example, in 2016 another study found that female mice had fewer eggs in their ovaries when their mothers received paracetamol during pregnancy. This caused these mice to become infertile more quickly. (as)

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Video: Medicine during pregnancy. Pregnancy 12 (January 2022).