Table 1: Subject demographics and menstrual cycle characteristics.

Parameter Mean Standard Deviation Minimum Maximum
Age (years) 20.9 2.9 18.0 28.0
BMI 24.1 3.3 19.6 31.8
Follicular Length (days) 16.1 3.2 12.0 24.0
Luteal Length (days) 13.1 2.4 8.0 16.0
Cycle Length (days) 29.0 3.3 19.0 36.0
Progesterone peak (ng/mL) 19.4 7.5 8.5 39.4
Relaxin peak (pg/mL) 49.6 30.5 15.0 118.0
Luteal day of Progesterone peak (days after ovulation) 5.3 2.3 1 10
Luteal day of Relaxin peak (days after ovulation) 8.4 2.0 3 10
Day of peak relaxin relative to peak progesterone 3.0 1.7 0 6