First Trimester: 9.3 – 33.2 
Second Trimester : 29.5 – 50.0 
Third Trimester: 83.1 – 160

Follicular Phase:  0.33 – 1.2 
Luteal Phase: 0.72 – 17.8 
Post-menopausal: ND – 1.0 
Oral Contraceptives: 0.34 – 0.92