What is the average fetal heart rate at 6 weeks?

Fetal heart rate. When the fetal heart rate is first seen by ultrasound it ranges from 100 - 120 bpm. The normal range later in pregnancy is 120 - 160. With fetal movement it is even higher.
Varies. . Average in the first trimester is about 150. When its first detected that early it can range from 120-160.