Obesity is a worldwide epidemic and can have a profound effect on pregnancy 
risks. Obese patients tend to be older and are at increased risk for structural 
fetal anomalies and aneuploidy, making screening options critically important 
for these women. Failure rates for first-trimester nuchal translucency (NT) 
screening increase with obesity, while the ability to detect soft-markers 
declines, limiting ultrasound-based screening options. Obesity also decreases 
the chances of completing the anatomy survey and increases the residual risk of 
undetected anomalies. Additionally, non-invasive prenatal testing (NIPT) is less 
likely to provide an informative result in obese patients. Understanding the 
limitations and diagnostic accuracy of aneuploidy and anomaly screening in obese 
patients can help guide clinicians in counseling patients on the screening 
options.