Testosterone might protect against inflammation, a study on mice suggests. Researchers found that administering a simple anti-inflammatory drug like ibuprofen to pregnant mice can increase survival rates in embryos.

During pregnancy, the body changes in a number of ways to protect the embryo, and as the pregnancy progresses, the fetus. For instance, inflammation in the mother’s body is oftentimes suppressed, so that the side effects don’t do any damage. However, not much is known about the consequences of maternal and fetal inflammation during pregnancy.

Inflammation is the natural process through which the body responds to injury and infection. Inflammation gets a lot of bad rep, but it’s actually an essential process associated with healing. Without inflammation as a physiological response, wounds would fester, and infections could become deadly. But inflammation can also be triggered by a perceived internal threat, even when there isn’t a disease to fight or an injury to heal and can cause problems in and of itself.

DNA damage is a well-known cause of inflammation. John Schimenti and colleagues from Cornell University wanted to investigate how DNA mutations (that caused defective DNA replication and repair during embryo development) affect the survival rates of mice embryos. They found that on average, male embryos were much more likely to survive than female embryos. The cause for this, researchers suspect, is testosterone, which can act as a common anti-inflammatory.

To confirm this theory, researchers administered pregnant mice ibuprofen, a non-steroidal anti-inflammatory drug (NSAID). After this treatment, survival rates for both males and females were equal, confirming the theory.

Testosterone is the primary male sex hormone. It’s also often seen as the underlying cause for male aggression, but the hormone actually interacts with the male body in numerous complex ways. This isn’t the first time testosterone has been highlighted as a potential way to treat inflammation — previous studies from 2013 all the way to 2019 have come up with consistent findings.

Journal Reference: The study “Female-biased embryonic death from inflammation induced by genomic instability” has been published in Nature. 10.1038/s41586-019-0936-6