Objective. To investigate the influence of Yarina Plus (ethynylestradiol/drospirenone/ calcium levofemolate) on homocysteine level in women with polycystic ovary syndrome (PCOS). Methods. Single-center, open labeled prospective parallel-group randomized controlled trial. 75 females (aged 26.7±1.8 years old) with PCOS diagnosed on the base of ESHRE/ASRM consensus (2003) were divided into 3 groups (n=25 each). Group 1 received EE/Drospirenone/calcium levomefolate, group 2 used non-folate combined oral contraception without folates (Yarina) and group 3 received no treatment. Results. Basal homocysteine levels in groups 1, 2 and 3 were 13.1±4.2 µmol/l, 12.9±5.0 µmol/l, 10.2±3.9 µmol/l, respectively. After 6 months of the therapy the homocysteine concentration decreased significantly in group 1 (8.7±2.5 µmol/l, (p<0,01); in groups 2 and 3 there was no significant changes (p>0.05). Conclusion. Folate-containing combined oral contraception is effective way of providing optimal folate level in patients with PCOS before planning pregnancy.