An ultrasound Doppler measuring the blood flow of small unborn babies can indicate whether the placenta is functioning correctly or not. When there are repeated deviations from these Doppler measurements, additional monitoring of the unborn baby is necessary. These deviations indicate a higher risk of oxygen deficiency and other health issues for the baby. This study, conducted by Amsterdam UMC in collaboration with UMC Groningen and 17 other Dutch hospitals, is published today in the British Journal of Obstetrics and Gynaecology.
Approximately 10% of unborn babies are considered small for their gestational age. If these babies are still healthy, there is no need for intervention during the pregnancy. However, in the case of small babies with placental dysfunction, action must be taken, and sometimes the birth of the child needs to be induced.
Therefore, it is incredibly important to identify which babies are smaller due to the placenta.“
Wessel Ganzevoort, Professor of Obstetrics at Amsterdam UMC and lead researcher of the study
For nearly 50 years, growth ultrasounds have been used to identify small babies and to see if they are following their own growth pattern or if they are beginning to grow at a slower rate. In this study, small babies were subjected to a „Doppler Ultrasound“ in addition to the standard growth measurement. This ultrasound measures the resistance of the blood vessels in the umbilical cord, which provides information about the blood flow to the placenta. The ultrasound can also measure the blood supply to the baby’s brain. If the supply is higher than usual, it may be a sign that the placenta is not functioning as well. The baby has then „opened“ the blood vessel in the brain to protect it from the deficiency caused by placental dysfunction. With a poorly functioning placenta, the risk of health problems (such as oxygen deficiency) in the child and ultimately mortality around birth increases.
Do Not Give Birth Before 37 Weeks
Part of the study also sought to determine if the results for the child were better when delivery was induced before the gestational age of 37 weeks. This did not lead to better outcomes. Therefore, it is recommended to wait until at least the 37th week of pregnancy to initiate labor. It is better for the baby to remain in the womb for as long as possible, as long as there are no additional risks for health problems.
„What is possible with a Doppler ultrasound was already known, but it is not yet common practice in all hospitals. This study now shows that this measurement can have added value in detecting pregnancies with undergrown babies with placental dysfunction,“ says Mauritia Marijnen, a doctoral candidate at Amsterdam UMC and first author of the study.
„By including this Doppler ultrasound in the care plan for these small babies, the higher risk of delivery problems can be better detected and monitored. Small babies with normal measurements can also be monitored less intensively. Therefore, there is a greater chance that delivery will occur naturally and without intervention,“ Ganzevoort concludes.
University Medical Center Amsterdam