As every mother knows, the fetus is constantly listening to the mother’s heartbeat, the sounds of her digestive system and even the music she plays outside the womb, but researchers believe the fetus hears more than just physical sounds. According to a study published in Psychological Science, chemical messages or psychological messages are also “heard” by the fetus.

When a mother is happy, chemicals are released and the fetus “hears” her mood. When a mother is sad, different chemicals are released so the fetus “hears” a different mood. According to researchers, these moods can affect how the infant develops throughout childhood and into adulthood.

Researchers have been studying the impact of the fetal environment in accordance with maternal life for decades. Links have been proven between health problems later in life and maternal environment. For instance, during the Dutch famine mothers were unable to eat enough food to provide proper nutrition to the fetus. Infants born to mothers pregnant during the famine were more likely to be obese and / or suffer from diabetes as adults. While these physical environmental factors are important, they are not the only factors affecting the fetus. Mood appears to have a significant impact on health.

What interested researchers most about the study was not the impact of depression or happiness on the fetus, but the impact of changing mood on the fetus. Mothers who were happy and healthy before pregnancy, during pregnancy and after pregnancy were just as likely to give birth to healthy offspring as mothers who were depressed before pregnancy, depressed during pregnancy and depressed after pregnancy. The offspring who had the most trouble were born to mothers who changed mood from depressed to happy and healthy or healthy and happy to depressed.

In a separate study, researchers found a physical change in brain structures in fetuses born to mothers who suffered from anxiety during pregnancy. There is no doubt that stress and depression play an important role in the mental health of offspring, but researchers are just as intrigued by the effects of changing mood. There were no physical changes to brain structure noted in this study.

Source: Curt A. Sandman, Elysia P. Davis, and Laura M. Glynn. University of California-Irvine. 13 November, 2011.