A negative fetal fibronectin test is highly predictive that preterm birth will not occur within the next what timeframe?

• A. One week
• B. Two weeks
• C. Four weeks
• D. Eight weeks

Answer: (A)

A negative fetal fibronectin test is most predictive that preterm birth will not occur in the near future, especially within the next week. This test looks for a protein released when the fetal membranes are stressed or starting to detach; if it’s not detected, the likelihood of delivery within about seven days is very low. Clinically, a negative result often supports conservative management—discharging the patient and avoiding aggressive interventions—while continuing to monitor and arrange follow-up. The predictive value diminishes for longer horizons (beyond about a week).