Table 1 Fetal behavioural states original criteria defined by Nijhuis et al. in 19822.
From: Evaluation of parameters for fetal behavioural state classification
State 1F | State 2F | State 3F | State 4F | |
|---|---|---|---|---|
Body movements | Incidental | Periodic | Absent | Continuous |
Eye movements | Absent | Present | Present | Present |
Heart rate patterns | Stable heart rate, with small oscillation bandwidth. Accelerations strictly related to movement | Wider oscillation bandwidth compared to 1F. Frequent accelerations related to body movements | Stable heart rate. No acceleration and higher oscillation bandwidth compared to 1F | Unstable heart rate. Long lasting accelerations, often with tachycardia |
