Noninvasive prenatal testing and maternal obesity: A review

Area of Science:

• Obstetrics and Gynecology
• Genetics
• Medical Diagnostics

Background:

• Noninvasive prenatal testing (NIPT) is a widely used screening method for common fetal aneuploidies.
• Maternal obesity is a known factor impacting NIPT performance, leading to higher rates of test failure or 'no-calls'.
• Existing guidelines for NIPT screening present varied and insufficient recommendations concerning maternal obesity.

Purpose of the Study:

• To systematically review medical literature, scientific society guidelines, and commercial NIPT provider information regarding NIPT no-calls in relation to maternal obesity.
• To assess the current landscape of recommendations and information available for managing NIPT in obese pregnant individuals.

Main Methods:

• Systematic literature search of MEDLINE for medical studies and scientific society guidelines.
• Systematic Google search for information materials from commercial NIPT providers.
• Analysis of nine medical studies and guidelines from 17 scientific societies, alongside information from 13 commercial providers, focusing on maternal obesity and NIPT no-calls.

Main Results:

• All nine included studies demonstrated a positive correlation between increasing maternal obesity (BMI) and NIPT no-call rates.
• No-call rates varied significantly, from 0-4.2% for normal BMI to 5.4-70.1% for BMI ≥40.
• While 76.5% of scientific societies acknowledged the link, only 17.6% advised against NIPT for severely obese women, and 30.8% of commercial providers mentioned obesity as a potential cause for no-calls.

Conclusions:

• Maternal obesity is a critical factor influencing NIPT accuracy and success rates, with a clear trend of increased no-calls.
• There is a notable lack of specific and consistent recommendations from scientific societies and commercial providers for NIPT in obese pregnant women.
• Updated and standardized recommendations are urgently needed to guide clinical decision-making for prenatal screening in this growing patient population.