Table 2: Levels of Oxytocin (OT), Seasonal Daylight Hours and Ratios of Oxytocin Levels in Women with and without Oral Contraceptives (OC).

Mean seasonal daylight hours

6 (Winter)

10 (Autumn)

15 (Spring)

Oxytocin level (pg/ml)

Study groups

Women with OC

430 212

370 215

405 207

Women without OC

301 149

332 186

263 138

Mean OT level

with OC/without OC

1.4

1.1

1.5