Genetics
Poster Session 3
Haley Crane, MS (she/her/hers)
Licensed Genetic Counselor
Richard D. Wood Jr. Center for Fetal Diagnosis and Treatment at CHOP
Philadelphia, PA, United States
Erica M. Schindewolf, MS
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Juliana S. Gebb, MD (she/her/hers)
Associate Professor
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Natalie Burrill, MS (she/her/hers)
Licensed Genetic Counselor II
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Lisa Pilchman, MS
Licensed Genetic Counselor II
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Renee Wright, MS
Genetic Counselor
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Suzanne DeBari, BS
Sonographer
Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia
Philadelphia, PA, United States
Beverly G. Coleman, MD
Professor, Director of Fetal Imaging
Richard D. Wood, Jr Center for Fetal Diagnosis and Treatment at CHOP, Perelman School of Medicine of the University of Pennsylvania
Philadelphia, PA, United States
Julie Moldenhauer, MD
Professor, Director of Obstetrical Services in the Center for Fetal Diagnosis and Treatment
Richard D. Wood, Jr. Center for Fetal Diagnosis & Treatment, Children's Hospital of Philadelphia, Perelman School of Medicine of the University of Pennsylvania
Philadelphia, PA, United States
Determining lethality in prenatally diagnosed skeletal dysplasia can be suspected using sonographic parameters with confirmation via molecular diagnosis. The challenge in the prenatal setting is that established ultrasound parameters are imperfect, while molecular diagnosis is not always achievable. We examined the added benefit of definitive genetic etiology in fetuses with suspected skeletal dysplasia when ultrasound was indicative of lethality.
Study Design: A single-center retrospective chart review was conducted from 2013-2023 for pregnancies suspected to have a skeletal dysplasia. Fetuses were evaluated by ultrasound with attention to measurements predictive of lethality, including thoracic circumference/abdominal circumference < 0.6, femur length/abdominal circumference < 0.16, and thoracic circumference < 2.5%ile. Record review included demographics, imaging, genetic testing, and fetal/neonatal outcome.
Results:
Of 122 pregnancies that met inclusion criteria, 88 had at least 1 ultrasound criteria suggestive of lethality. Among suspected lethal cases, 79 underwent genetic screening/testing prenatally (64.6%), postnatally (20.3%), postmortem (10.1%), or at multiple points (5.1%). Genetic testing revealed non-lethal molecular diagnoses in 16 (20.3%) pregnancies thought to be lethal by ultrasound. In 39 cases with only 1 measurement in the lethal range, genetic testing identified lethal, non-lethal, and indeterminate results in 15 (38.5%), 14 (35.9%) and 10 (25.6%) patients, respectively. When presenting in the 3rd trimester, a higher portion of fetuses harbored non-lethal versus lethal genetic diagnoses, although this was not statistically significant (6/10 vs 4/10; p=0.25).
Conclusion:
A discordant outcome from suspected lethal was revealed via non-lethal genetic diagnoses in 20.3% of cases. This data emphasizes the value of genetic testing in corroborating or refuting ultrasound prediction of lethality. A combination of ultrasound findings and molecular diagnosis can paint the clearest picture of prognosis, ultimately aiding in counseling, familial decision-making, and delivery planning.