Table 2 Accuracy of gestational age assessment by method
Method of Gestational Age Assessment | Accuracy Correctiona,b,c | Accuracy Scaled |
|---|---|---|
Ultrasound before 14 gestational weeks | ±5 days | 1 (most accurate) |
Ultrasound between 14 and 28 gestational weeks | ±2 weeks | 2 |
Ultrasound after 28 gestational weeks | ±3 weeks | 3 |
Ballard score within 7 days of birth | ±2 week | 4 |
LMP | ±4 weeks | 5 |
Fundal Height | ±6 weeks | 6 (least accurate) |