Effects of Low-dose Oral Contraceptives on Blood Coagulation. Issue 5612 (27th July 1968)

• Record Type: Journal Article
• Authors: Poller, L.; Tabiowo, Anne; Thomson, Jean M.
• Is Part Of: BMJ. Volume 3:Issue 5612(1968)
• Page Start: 218
• Page End: 219
• Publication Date: 1968-07-27
• Subjects: Medicine -- Periodicals; Medicine -- Periodicals; Medicine; Periodicals; 610
• DOI: 10.1136/bmj.3.5612.218
• Languages: English
• ISSNs: 0007-1447

Abstract

Abstract : A study has been performed on the effect of Norinyl-1 and Ortho-Novin, two low-dose oral contraceptives, on blood-clotting factors. Ortho-Novin contains twice the amount of hormone as Norinyl-1. It was therefore possible to observe whether any changes detected were related to the dose of oestrogen-progestin combination. The women were tested in parallel with matched normal female controls and a group in the third trimester of pregnancy. Significant rises in factor VII and X levels were found with both low-dose preparations from the third month onwards. There was no difference between patients on Norinyl-1 and Ortho-Novin, and hence the clotting changes do not appear to be dose-dependent. The long-term effects on clotting factors of these low-dose oral contraceptive preparations remain to be investigated.