Many expectant mothers will have three ultrasounds during their pregnancy, according to Dr. Robert Welch, Director of Maternal Fetal Medicine at Hurley Medical Center. “Most women have at least one,” he reports. An ultrasound is given for multiple reasons: to confirm the due date, establish fetus count, measure growth and possibly even learn the gender.
Why is ultrasound important during a pregnancy? “Ultrasound is one of the most significant breakthroughs in perinatal care,” says the doctor. “It is used to assess the baby’s health and it can diagnose many abnormalities.” A Level III Obstetric Ultrasound is one performed in a nationally certified unit. There, a sonographer not only measures growth of the baby, but also looks at anatomy, amniotic fluid, the placenta, the mother’s ovaries, and surrounding tissues. “If an abnormality is discovered or suspected,” adds Dr. Welch, “It may lead to additional diagnostic testing.” That can make a difference in terms of what experts may be needed to treat the newborn.
“Ultrasound is one of the most significant breakthroughs in perinatal care. It is used to assess the baby’s health and it can diagnose many abnormalities.”
— Dr. Robert Welch
Ultrasounds are often performed in each trimester of the pregnancy, Dr. Welch explains. In the first-trimester (up to 14 weeks), they want to make sure the baby is in the uterus where it belongs, to confirm the number of babies, and to determine when the baby is due. “We know that more than 50% of the time, the last menstrual period is not an accurate way to determine the due date. That is a key value of the first-trimester ultrasound,” he adds.
The second trimester (particularly between 18-22 weeks) ultrasound can be critical. “The ultrasound assesses growth and most babies have large enough features to evaluate their presence and position within the womb. We can also evaluate bony structures like fingers and toes and determining gender at this stage is often an added benefit. However, determining gender is NOT a reason for having an ultrasound!”
The third trimester (more than 28 weeks) ultrasound mostly measures fetal growth. Babies growing on the small side may not be getting enough oxygen and nutrients. This condition is known as Fetal Growth Restriction (FGR) and it can be dangerous as it may precede stillbirth. FGR is monitored using umbilical artery Doppler, a diagnostic technique that requires special expertise to interpret as it often predicts when the baby should be delivered.
Most obstetrician’s offices do not have this capability, so if a baby’s growth is determined to be a concern, the mother is usually referred to a perinatal center, like Hurley Medical Center. “Doppler often informs us whether the baby is at risk for stillbirth,” Dr. Welch points out. “Using Doppler and other advanced techniques leads to a balancing act to determine when the baby is better off inside the mother’s womb, as compared to inside the Neonatal Intensive Care Unit. Over the past several years, using Doppler, we have prevented many stillbirths.”
According to Dr. Welch, Doppler is also part of evaluating the baby’s heart (fetal echocardiogram) in circumstances when there may be suspicion or family history of heart defects. The standard prenatal ultrasound test can give information about whether the fetal heart has developed with all four chambers and outflow tracts (pulmonary and aortic arteries). Most pregnant women don’t need further imaging of their baby’s heart if their regular second trimester ultrasound is normal. In some conditions, like maternal diabetes or family history of heart defects, additional imaging may be needed. “Through fetal echocardiography, we can predict the heart function before the baby is born,” says Dr. Welch, adding that it also helps to determine if the baby should be born in a high-risk center such as Hurley.
Dr. Welch has been in the field of maternal-fetal medicine for 30 years. “With these technologies, we can avoid unfortunate surprises during childbirth, letting the family focus on the happy moments.”
“Through fetal echocardiography, we can predict the heart function before the baby is born.”
Robert A. Welch, MD, MSA, FACOG
Dr. Welch is double board certified in both Obstetrics & Gynecology and Maternal-Fetal Medicine. He is a graduate of Louisiana State University Medical Center in New Orleans and completed his residency and fellowship at Wayne State University/Detroit Medical Center. He has participated in several leadership roles throughout his career including being a director of maternal-fetal medicine at both the university and community hospital levels, a department chair and, vice president for women’s services. He regularly participates in local and national research projects, speaks on topics in high-risk obstetrics, and is significantly involved in medical student and resident physician education. He is the director of Maternal-Fetal Medicine and the Diabetes in Pregnancy Program at Hurley Medical Center. His practice is by referral from area obstetricians and midwives.