RESUMO
In 15 females who have never before taken oral contraceptives, the porphyrin concentration in erythrocytes and in urine were investigated. The laboratory assays were performed before and after being on the oral contraceptive Stediril during 5 months (2 women took Stediril during only 3 months). The mean PP concentration in the erythrocytes increased from 16.4 microgram (before) to 24.1 microgram/100 ml of erythrocytes after taking Stediril regularly for 5 months. A statistical evaluation with the Student's test showed that at the level of 2%, the t(exp) = 2.58 was larger than the theoretical t(0.02) = 2.47. The difference of the mean CP concentration in the erythrocytes before and after taking Stediril was not statistically significant at the level of 5%. The mean concentration of CP in urine increased from 119.2 to 137.1 microgram in 1,000 ml. This difference was, however, not statistically significant at the level of 5% when assayed with the same test. There was no increase in UP concentration in urine.
PIP: Porphyrin concentrations in erythrocytes and in urine were investigated in 15 females who had never taken oral contraceptives (OCs). Laboratory assays were performed before and after ingesting the OC Stedril (.5 mg of norgestrol and 50 mcg of ethinyl estradiol) during 5 months (2 women took Stedril during only 3 months). The mean protoporphyrin concentration in the erythrocytes increased from 16.4-24.1 mcg/100 ml of erythrocytes after taking Stedril regularly for 5 months. A statistical evaluation with the Student's t test showed that at the level of 2%, the texp=2.58 was larger than the theoretical t0.02=2.47. The mean concentration of CP in urine increased from 119.2-137.1 mcg/1000 ml. The difference was not statistically significant at the level of 5% when assayed with the same test. There was no increase in uroporphyrin concentration in urine. The porphyrinogenic effect of small doses of natural estrogens was demonstrated.