Most people love taking a cup of coffee to feel fresh and alert.
The beverage has become a staple in most home and offices, with many people viewing it as harmless.
But as the saying goes, too much of something may be dangerous. This is especially true for pregnant women.
Findings of a recent study published in the Endocrinology Journal show that having too much caffeine during pregnancy may impair the unborn baby’s liver development and increase the risk of liver disease in adulthood.
The research, conducted among laboratory mice found that pregnant mice given caffeine had offspring with impaired liver development as well as altered growth and stress hormone levels.
It revealed that consumption of caffeine equivalent to between two and three cups of coffee might alter stress and growth hormone levels in a manner that can impair growth and development, whilst increasing the risk of liver disease among affected children in adulthood.
The research findings were in line with previous animal studies that have suggested that prenatal caffeine consumption may have more detrimental long-term effects on liver development, with increased susceptibility to non-alcoholic fatty liver disease — a debilitating condition normally associated with obesity and diabetes.
Irrespective of these risk factors, the underlying link between prenatal caffeine exposure and impaired liver development remains poorly understood.
The new study thus sought to provide a better understanding of how caffeine mediates these effects.
During the research, scientists from Wuhan University in China investigated the effects of low caffeine (the equivalent of between two and three cups of coffee) and high doses of caffeine (the equivalent of between six and nine cups of coffee) on liver function and hormone levels in the offspring of pregnant rats.
The results showed that offspring exposed to prenatal caffeine had lower levels of a hormone known as an insulin-like growth factor (IGF-1) that is produced in the liver, as well as a stress hormone called corticosteroid at birth.
The IGF-1 hormone is important for normal growth. Its suppression, therefore, impedes the proper functioning of the body as well as the liver.
To rectify this challenge, the research revealed that after birth, the liver of affected mice offspring ended up producing increased levels of the hormone to compensate for the earlier deficit caused by the caffeine to enhance proper body development.
The researchers believe that the increased risk of fatty liver disease to unborn children associated with caffeine exposure during pregnancy is most likely a consequence of this enhanced IGF-1 production in the offspring after birth.
According to the researchers, these findings confirm that prenatal caffeine exposure leads to impaired liver development before birth.
However, they note that the animal findings need to be confirmed in humans first.
“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,” said Dr Yinxian Wen, co-author of the study from the Wuhan University in China.
Aside from increasing the risk of liver disease — caffeine as a stimulant — is known to elevate blood pressure and heart rate, both of which are not recommended during pregnancy.
High blood pressure can increase the risk of poor birth outcomes, such as preterm delivery, smaller-than-average size babies and infant death.
It also affects the mother’s blood vessels. This can decrease the flow of nutrients through the placenta to the baby, resulting in low birth weight.
Hypertension-related preterm delivery can also result in health complications for the baby. These may include difficulty breathing if the lungs are not fully developed.
Being a diuretic, caffeine also increases the frequency of urination. This causes a reduction in body fluid levels, leading to dehydration
Mild dehydration is not typically dangerous in pregnancy as long as the woman quickly gets enough fluids.
However, severe dehydration caused by caffeine can be dangerous for both the mother and the baby.
It lowers levels of amniotic fluids, which can influence the baby’s development, leading to preterm labour while also affecting the production of breast milk.
Dehydration can cause deficiencies in nutrients that are vital for the health of the pregnant woman and the developing baby.
Health experts note that although adults may be able to handle the amounts of caffeine that they consume in their bodies, babies cannot.
This is because their still maturing metabolism cannot fully breakdown the caffeine.
They note that any amount of caffeine can also cause changes in the baby’s sleep pattern or normal movement in the later stages of pregnancy.