Researchers from Imperial College London have found that a rare metabolic complication among pregnant women programs babies to become overweight later in life.
Researchers from Imperial College London conducted a first of its kind study to determine the effects of a rare metabolic complication during pregnancy called intrahepatic cholestasis of pregnancy (ICP) on babies born to such mothers. Also known as obstetric cholestasis, this disorder is characterized by a build-up of bile acids in the bloodstream.
For the study, researchers looked at babies born in Northern Finland between 1985 and 1986 and identified 45 babies who were born to mothers with ICP. All these babies were found to be of healthy weight and had no diseases or complications, such as diabetes. There was no significant difference is such babies' weight when compared to babies born to mothers without ICP. However, by the time these babies became 16 years old, boys were found to have up to four points higher body mass than other boys of the same age. Also, after fasting, the boys born to mothers with ICP were found to have higher levels of the hormone insulin, which is a sign of diabetes.
Girls born to mothers with ICP had broader waists by up to 9cm and hips by up to 5cm compared with girls born from normal pregnancies.
"We don't yet know the exact mechanisms of how the increase in bile salts in the mothers' blood programs the unborn baby towards metabolic disease but it seems likely that epigenetics plays a role. We need to do more experiments to work out how these chemical changes to the DNA of the baby affect its ability to metabolise fats," Professor Catherine Williamson, lead author of the study from Imperial College London and King's College London, said in apress release.
To investigate the findings further, researchers created a mouse model of the disease by supplementing the diet of normal mice with cholic acid, a type of bile acid. Researchers observed that mice born from these pregnancies were more likely to become obese and be affected by diabetes.
The authors of the study stated that this could be because of an increased amount of fats and excessive cholesterol transport in placentas from mothers with ICP compared with healthy mothers.
