Effect of oral contraceptive agents on thiamin status.

A cross-sectional and follow up study of oral contraceptive agent (OCA) users revealed no adverse effects of OCA on erythrocyte transketolase activity (ETK) or thiamin pyrophosphate effect (TPP effect). In the cross-sectional study group, thiamin intake was below the recommended in only 19.2 per cent subjects and thiamin intake/100 kcal/day revealed a significant negative correlation with TPP effect. Routine prophylactic administration of thiamin was not indicated in OCA users.