Folate status and homocysteine levels during a 24-week oral administration of a folate-containing oral contraceptive: a randomized, double-blind, active-controlled, parallel-group, US-based multicenter study.

Background: This study investigated the effects of adding levomefolate calcium 0.451 mg (the calcium salt of L-5-methyltetrahydrofolate; Metafolin®) to an oral contraceptive containing ethinylestradiol (EE) 20 mcg/drospirenone (drsp) 3 mg on folate levels in healthy women seeking contraception.

Study Design: In this randomized, double-blind, multicenter US-based study, women (18-40 years) received 24 weeks (six cycles) of EE/drsp/levomefolate calcium or EE/drsp for 24 days followed by 4 days of levomefolate calcium alone or placebo, respectively. The primary efficacy variables were red blood cell (RBC) and plasma folate levels at 24 weeks.

Results: At week 24, increases from baseline in mean RBC (990 ± 390 nmol/L to 1406 ± 440 nmol/L) and plasma folate (45.0 ± 17.6 nmol/L to 60.8 ± 19.9 nmol/L) levels were observed in women who received EE/drsp/levomefolate calcium [per protocol set (n=262); all values are displayed as mean ± standard deviation]. In contrast, marginal fluctuations were observed with EE/drsp (p<.0001 for between-treatment differences at week 24).

Conclusion: Clinically significant increases in folate status were observed with EE/drsp/levomefolate calcium compared with EE/drsp alone in US women of childbearing age.