Fetal medicine in the 1980s
Fetal medicine in the 1980s marked a significant advancement in the care and assessment of unborn children, catalyzed by the introduction of various diagnostic technologies and procedures. One of the key innovations was the biophysical profile (BPP), which assessed several indicators of fetal health, enabling early detection of distress and improving outcomes through timely intervention. Blood tests for biochemical markers such as alpha-fetoprotein (αFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) emerged as essential tools for identifying genetic disorders, including Down syndrome, in utero.
Ultrasound technology advanced significantly during this decade, allowing for procedures like percutaneous fetal blood sampling (PUBS), which facilitated both diagnostic testing and therapeutic interventions for conditions like Rhesus incompatibility. Pioneering fetal surgeries, starting with urinary tract obstruction treatments, further underscored the potential for correcting congenital anomalies before birth. This period also saw the introduction of laser therapy to manage twin-twin transfusion syndrome, showcasing the evolving capabilities of fetal medicine.
Overall, these advancements contributed to a dramatic decrease in perinatal mortality and heightened public awareness of prenatal care challenges. Despite the progress, access to these life-saving interventions remained uneven, raising important discussions about ethical considerations and the status of the unborn as patients.
Fetal medicine in the 1980s
Maintenance of health and detection and treatment of diseases in unborn children
Fetal medicine gained prominence in the 1980’s as a medical specialty. Accurate and detailed assessment of the health of unborn children was made possible through the use of high-resolution ultrasound. Malformations, illnesses, and poor fetal growth became diagnosable and even treatable before birth.
In the early 1980’s, the introduction of biophysical profile (BPP) scoring greatly facilitated the assessment of fetal health. The BPP assessed fetal movement, tone, breathing, heart rate accelerations, and amniotic fluid volume. A high BPP score indicated a healthy fetus, while a low score reflected a fetus in trouble. Early recognition of a harmful uterine environment allowed timely delivery of the fetus and circumvented complications such as stillbirth or brain damage due to lack of oxygen.
Diagnostic Technologies
Advances in fetal medicine also made it possible to detect genetic disorders in an unborn child by screening an expectant mother’s blood for specific biochemical markers. The first routinely used marker was alpha-fetoprotein αFP). Elevated αFP levels required detailed evaluation of the fetus for malformations such as spina bifida and anencephaly. Tests for other biochemical markers—human chorionic gonadotropin (hCG) and unconjugated estriol (uE3)—arrived in the latter part of the decade. Testing the mother’s blood for these three markers helped identify approximately 60 percent of fetuses with Down syndrome.
Improved ultrasound imaging techniques made the fetus itself directly accessible for diagnostic testing. Under ultrasound visualization, a needle could be guided through the mother’s abdomen into an umbilical cord vessel and fetal blood could then be drawn for laboratory examination. This procedure, known as percutaneous fetal blood sampling (PUBS) or cordocentesis, was also used to give the unborn child medications or blood products. A mother whose blood is Rhesus negative may form antibodies against the red blood cells of her baby if it is Rhesus positive. These maternal antibodies destroy the fetus’s red blood cells and cause severe, life-threatening anemia. With the help of PUBS, these fetuses could be transfused during pregnancy until it became safe to deliver them.
Fetal Surgery
The ability to visualize an unborn child in great detail allowed early discovery of organ malformations that caused death or were associated with poor long-term neurodevelopment. The thought arose that correction of these anomalies before birth might increase the child’s chances of survival or improve its neurologic outcome.
Normal growth of a fetus’s lungs requires the presence of amniotic fluid. Fetal urine is an important component of amniotic fluid, and fetuses with no kidneys or poorly functioning kidneys produce little to no urine and die rapidly after delivery. Some fetuses have an obstruction in their urinary tract that does not allow urine to flow freely out of the bladder into the amniotic cavity. In 1981, Michael Harrison and his colleagues performed the first fetal surgery in the United States on a fetus with urinary tract obstruction, facilitating the flow of fetal urine from the bladder into the amniotic sac.
Ultrasound imaging also facilitated antenatal diagnosis of hydrocephalus, a buildup of cerebrospinal fluid (CSF) within the skull that can lead to mental retardation. In the second fetal surgery conducted in the United States, William Clewell and his colleagues placed a drain in a fetus with hydrocephalus, thus allowing the CSF to empty into the amniotic cavity.
Congenital diaphragmatic hernia (CDH) represents a defect in a fetus’s diaphragm that leads to entry of abdominal contents such as intestine, spleen, or liver into the chest cavity. This malformation impairs good lung growth and is associated with a high mortality rate. The first repair of CDH in a fetus occurred in 1983. Other fetal surgeries performed in the 1980’s included removal of large spinal tumors (sacrococcygeal teratomas) and resection of large lung masses (congenital cystic adenomatoid malformation).
Identical twin pregnancies can be complicated by twin-twin transfusion syndrome (TTTS). In such cases, one twin will be very anemic while the other twin is overwhelmed by excessive blood flow. Such a condition can lead to the death of both fetuses. The cause of TTTS appears to be an imbalance of blood flow due to communicating blood vessels in the placenta. In 1988, Julian De Lia, with the help of laser therapy, was able to interrupt these vascular communications to treat TTTS effectively.
Impact
During the 1980’s, the improved ability to detect a fetus in distress led to a dramatic decline in perinatal mortality. Routine screening of multiple biochemical markers allowed early identification of genetic disorders and brought issues such as termination versus continuation of pregnancy to the forefront of public consciousness. The ability to transfuse a fetus greatly improved the survival of Rhesus-sensitized babies. Even though the media enthusiastically reported stories about “miracle” babies, however, only about 35 percent of fetuses actually survived surgery, and little is known about the quality of life of those that lived. Moreover, although medicine’s ability to provide health care for the unborn seemed almost limitless, adequate prenatal care was not universal, and fetal intervention was limited to a select few. These rapid advances in fetal medicine allowed unborn children to acquire the status of patients in themselves.
Bibliography
Brunner, Joseph. “In Their Footsteps: A Brief History of Maternal-Fetal Surgery.” Clinics in Perinatology 30, no. 3 (September, 2003): 439-447. Introduces four pioneers of fetal surgery and their accomplishments.
Caspar, Monica, ed. “Fetal Matters.” In The Making of the Unborn Patient. New Brunswick, N.J.: Rutgers University Press, 1998. Critical analysis of fetal surgery; discusses low success rates, risks to mothers, and ethical issues.
Manning, F. A. “Reflections on Future Directions of Perinatal Medicine.” Seminars in Perinatology 13, no. 4 (August, 1989): 342-351. Reports the impact high-resolution ultrasound had on the rapid development of maternal-fetal medicine.
Scioscia, Angela. “Prenatal Genetic Diagnosis.” In Maternal-Fetal Medicine, edited by Robert Creasy and Robert Resnik. Philadelphia: W. B. Saunders, 1999. Description of biochemical markers used to detect fetal anomalies.