Preventing and diagnosing defects before birth
According to the CDC, birth defects affect 1 out of 33 births in the U.S. with cleft lip/palate, heart defects and spinal bifida among the most common. We now know that taking 400 mcg folic acid (or the active form called l-methylfolate) before and during pregnancy can cut down on the rate of neural tube defects, cleft lip and palate and potentially heart defects. 10-25% of mothers may have a defective enzyme MTHFR that cannot use folic acid but may benefit from l-methylfolate. Choline, an underappreciated B vitamin plays an equally important role in preventing Spina Bifida and is low in many women’s diets. Choline is low in vegetarian/vegan diets and is found in meat, eggs, liver and seafood. Choline supplements are recommended if intake is low.
All women even thinking about getting pregnant need a good prenatal vitamin with 400 mcg folate. Avoidance of drugs, alcohol and certain medications when pregnant are also key in preventing defects.
Despite our best efforts, birth defects are still a relatively common occurrence. This underscores the importance of good prenatal care, including use of high-resolution fetal ultrasound by a qualified OB, Perinatologist or CNM for early diagnosis to improve outcomes. A recent advance in prenatal diagnosis is the use of Fetal MRI. A fetal MRI is noninvasive and offers detailed information about anatomic structures of the fetus without radiation, providing clear, high-resolution images. Fetal MRI can supplement the information obtained from ultrasound and can provide additional information regarding a baby’s diagnosis. It is performed in the 2nd or 3rd trimester of pregnancy by radiologists specifically trained in this mode of testing. Fetal MRI is now being used to evaluate abnormalities prenatally in the baby's brain, spine, and body, and may be used to confirm an ultrasound diagnosis or add significant diagnostic information in complex cases.
In one of the first cases of its kind, fetal MRI was used to evaluate a baby with a congenital diaphragmatic hernia by physicians at Montana Children’s. Congenital diaphragmatic hernia (CDH) is a birth defect that occurs in 1 in 3800 births when a baby’s diaphragm doesn’t form correctly during fetal development, typically around 9 to 10 weeks’ gestation. This leaves an opening between the chest and abdominal cavities, allowing abdominal organs to herniate into the chest cavity and prevent lung development.
Our pediatric radiologist along with pediatric surgeons, maternal-fetal medicine specialists, neonatologists and pediatric anesthesiologists had multiple meetings to discuss the safety of delivery in Montana, versus transferring out of state. Using the calculated lung volumes from fetal MRI allowed the team to confidently counsel the parents regarding prognosis and surgical repair. The baby was delivered at Kalispell Regional Medical Center and underwent successful surgical repair under the care of our multidisciplinary team. The baby is currently thriving and happy, without having to leave our great state.
By Federico Seifarth, MD, pediatric surgeon, and Adriane Haragan, MD, maternal-fetal medicine specialist, of Montana Children's.
This article was originally published in MT Pediatric Updates - Provider Newsletter issue No.1 (Jan/Feb 2020).