Having two or three cups of coffee each day while pregnant may impair the baby’s growth and development, according to a new study.
Researchers at Wuhan University in China have investigated the effects of caffeine, given to pregnant rats, on liver function and hormone levels of their offspring, and they found that consuming the caffeine equivalent of two to three cups of coffee per day may alter their stress and growth hormone levels in a way that can impair growth and development, and increase the risk of liver disease in adulthood.
Offspring exposed to the prenatal caffeine had lower body weights, lower levels of the liver hormone, insulin-like growth factor (IGF-1), and higher levels of the stress hormone, corticosteroid, at birth. However, researchers also found that liver development after birth went through a “catch up phase”, as evidenced by increased levels of IGF-1.
“Our results indicate that prenatal caffeine causes an excess of stress hormone activity in the mother, which inhibits IGF-1 activity for liver development before birth,” said study co-author Dr. Yinxian Wen. “However, compensatory mechanisms do occur after birth to accelerate growth and restore normal liver function, as IGF-1 activity increases and stress hormone signalling decreases.
The increased risk of fatty liver disease caused by prenatal caffeine exposure is most likely a consequence of this enhanced, compensatory postnatal IGF-1 activity.
“Our work suggests that prenatal caffeine is not good for babies and although these findings still need to be confirmed in people, I would recommend that women avoid caffeine during pregnancy.”
These findings confirm earlier research which discovered prenatal caffeine exposure leads to lower birth weight and impaired liver development before birth. It also expands the understanding of the underlying hormone changes behind these discoveries.