A study undertaken for a Swedish doctoral thesis presents evidence that obesity on the part of an expectant mother makes it more difficult to use ultrasound to detect serious physical defects in a fetus.
Eric Hildebrand, senior physician at the Linköping University Hospital Women’s Clinic in Linköping, Sweden, defended his thesis earlier this month. He is a doctoral candidate in obstetrics and gynecology at Linköping University.
Dr. Hildebrand wants to detect fetal abnormalities in order to give babies the best chance of survival after birth:
The lives of children with serious heart defects are in constant danger. Some of them need immediate operations or medical treatment. If these defects are detected during the pregnancy, the babies can be born in Lund or Gothenburg, where the hospital has facilities for child heart surgery.
He was quoted in a Linköping University news release.
Dr. Hildebrand studied more than 21,000 ultrasound scans that were done in the southeastern part of Sweden under the auspices of the government maternity health care system. He described the subjects as “a low-risk population from a mainly rural setting.” Each expectant mother received two scans, one during the first trimester and one during the second.
The data showed that the rate of detection of fetal “structural anomalies” was less when the mothers were obese—with a body mass index of 30 or higher—than when the mothers were underweight, normal weight, or overweight. “Subcutaneous fat detracts from the quality of the image, making it more difficult for us to see malformations,” Dr. Hildebrand said, as quoted in the news release.
In his thesis, Dr. Hildebrand mentioned some of the troubling implications of that finding. “Obesity is increasing dramatically worldwide,” he wrote, “and this emphasizes the need to evaluate the impact of obesity on the methods of prenatal diagnostics as it is not satisfactory to offer a screening procedure that does not provide the same quality for both the thin and the obese.”
Related CME seminar (up to 17 AMA PRA Category 1 credits™): Fetal and Women’s Imaging: Advances in Ob-Gyn Ultrasound, with Emphasis on the Fetal Heart