Effect of contraceptive steroids on creatine kinase activity in serum.

Abstract

Administration of steroids has been reported to decrease creatine kinase (CK; EC 2.7.3.2) activity in sera of patients suffering from various diseases. Recently one of us reported a decrease in serum CK activity in healthy women of reproductive age taking a contraceptive steroid (Primovlar Schering) for 9 months. We continued to study to investigate the effect of another contraceptive steroid preparation (Ovulen Searle) on serum CK. CK activity was measured in sera of 10 healthy women of reproductive age 3 6 and 9 months after they started taking Ovulen and in 20 healthy women of comparable age (control group) as described earlier. The data were analyzed statistically by Students t-test. There was no significant difference (p>0.05) in the serum CK activity of control subjects and women taking Ovulen for 3 6 and 9 months. All the individual values were within the normal range. We conclude that the serum CK-lowering effect of contraceptive steroids depends on the specific steroids involved. Both Primovlar and Ovulen are estrogen/progestogen combinations but Primovlar contains 0.05 mg of ethinyl estradiol and 0.5 mg of norgestrel and Ovulen contains 0.1 mg of mestranol and 1.0 mg of ethynodiol diacetate. (full text)