Operation for obesity and low blood sugar

In Denmark, a gastric bypass is the most usual form of surgery for obesity, and it is often performed on women of childbearing age. Weight loss before pregnancy with the help of a gastric bypass reduces complications in pregnancy caused by obesity. There is a reverse side to the coin, however. One aspect is low blood sugar, which during pregnancy may cause a risk for both the foetus and the mother.

A sudden drop in blood sugar can lead to dizziness, and at the worst to falling accidents. Normally, the individual is warned, e.g. by sweating, flushing or by trembling hands. If the blood sugar drops frequently, the body will become accustomed to it, so there is no warning. This is a highly dangerous situation, since the first symptom of low blood sugar may be unconsciousness.

“The support of the Vissing Foundation will enable us to investigate the occurrence of low blood sugar in pregnant women with a gastric bypass. We will also investigate whether the growth of the foetus is affected by the situation,” says Louise Laage Stentebjerg, physician and PhD student at the Steno Diabetes Center Odense, at Odense University Hospital.

The researchers will make use of meal tests, continual transcutaneous blood sugar monitoring, and ultrasound scans of the foetus during pregnancy. They will also examine the body composition of the infant immediately after birth.

“It is essential to study this patient group in more detail, so that we can clarify which women are at risk of repeated drops in blood sugar. With that knowledge it will be possible to prevent dangerous situations, and it will lead to better quality of life.” says Louise Laage Stentebjerg.

Gastric bypass is a well-established treatment of obesity, most often performed in women during their reproductive years. While weight loss as a consequence of gastric bypass is beneficial before pregnancy as it diminishes obesity related complications, the operation prompts complications. Among these are low blood sugar. Low blood sugar presents with non-specific symptoms causing decreased quality of life. In worst case, low blood sugar can cause fainting and fatal accidents if occurring unwarned. Normally, warning signs appear with symptoms such as flushing and sweating. However, recurring events of low blood sugar can cause adaptation resulting in no warning signs before unconsciousness.

The occurrence of low blood sugar among pregnant women with gastric bypass surgery will be investigated as well as whether fetal growth is affected by events of low blood sugar. In order to do so, meal tests, continuous blood sugar measurements with a sensor inserted in the skin and ultrasound estimation of fetal weight are performed during pregnancy. At birth the newborn’s body composition will be examined.

It is essential to identify women at risk of low blood sugar in order to prevent fatal accidents and increase quality of life.