Clinical Implications of Noninvasive Prenatal Testing Failures Due to Low Fetal Fraction: Associations With Adverse Maternal and Fetal Outcomes

OBJECTIVE: To identify risk factors associated with noninvasive prenatal testing (NIPT) failures due to a low fetal fraction (LFF, < 4%) and to evaluate appropriate management strategies. METHODS: This was a single retrospective cohort study conducted on consecutive NIPT procedures performed at a national prenatal diagnosis center between April 2016 and June 2022. RESULTS: (OR 8.1), low molecular weight heparin administration (OR 7.7), systemic lupus erythematosus (OR 6.1), and dichorionic twins (OR 2.1). NIPT failure was also associated with a higher incidence of gestational hypertension (2.9% vs. 0.7%; OR 4.0), preeclampsia (9.1% vs. 1.0%; OR 10.4), gestational diabetes mellitus (26.0% vs. 11.8%; OR 2.6), fetal growth restriction (4.7% vs. 0.9%; OR 5.4), spontaneous abortion (2.4% vs. 0.6%; OR 4.1), and preterm birth (10.0% vs. 3.6%; OR 3.0). CONCLUSIONS: Pregnancies with NIPT failures are at a heightened risk for fetal chromosomal abnormalities and placenta-mediated complications, highlighting the need for enhanced monitoring and individualized management during perinatal care.