The effect of ovarian steroids on sickle cell deformability.

Sickle cell disease (SCD) is an incurable debilitating disease affecting the Afro-Caribbean population. The combined oral contraceptive pill (COCP), an effective and popular method of contraception, is often denied to women with SCD for fear that the disease process may have a synergistic effect on the coagulation changes associated with contraceptive steroids. In this study red cell deformability was assessed in 10 women with SCD and 10 comparable women with normal AA haemoglobin. Neither group was on exogenous hormones. The red cells were taken in the follicular phase of the menstrual cycle when women have low endogenous levels of oestradiol and progesterone. The effect of the steroids contained in the COCP on red blood cells was simulated by incubation with therapeutic concentrations of oestradiol and progesterone. Red cell deformability is a measure of the ease with which erythrocytes flow through small capillaries and was assessed using the parameters red cell transit time (RCTT) and clogging rate (CR). Therapeutic concentrations of oestradiol and progesterone did not appear to influence red cell deformability in women with SCD or normal AA haemoglobin.