Effect of Combined Oral Contraceptive Pills on Renal Function Tests

Background: Controversy exists regarding the adverse and beneficial effects of oral contraceptive use. Microalbuminuria is associated with increased risk of renal and cardiovascular disease. There are very little studies to determine the effects of combined oral contraceptive pills (COCPs) on renal function tests including detection of microalbuminuria in hormonal contraceptive users at least in our locality. Objective: To evaluate the effects of COCPs on serum urea, creatinine and electrolytes level and creatinin clearance and to detect microalbuminuria (MAU) in COCPs users and in relation to the blood pressure (BP) changes and duration of their usage in Mosul City. Subject & Methods: This is a case control study in which a total of 47 healthy married women , age range between 19-35 years, from those who were attending AL–Batool and AL-Khansa Family Planning Centers in Mosul from the period of 15 Oct 2010 to the 15 of Apr 2011, who were taking Microgynon tablets which are one of monophasic , second generation COCPs (each contains 0.03 mg of ethinly estradiol and 0.15 mg levonorgestrel) for a period ranged between 3 months to 5 years and these were considered the users group. Another 51 healthy married women who did not use any hormonal contraceptives and were drawn from the same population and matched for age, body mass index (BMI) with the users group and they were considered as the non users groups. Blood samples (5ml) and urine samples (5ml) were obtained from COCPs users and non-user groups. nkkjThe sera obtained from the blood samples were used for the estimation of serum urea, serum creatinine by commercial kits. Serum electrolytes level was measured using OPTI LION Stat Electrolyte Analyser. Creatinine clearance was calculated using Cockroft and Gault equation. The urine samples were used for the detection of microalbuminuria using i-chroma reader system. Results: This study demonstrated that using of COCPs caused a significant increase in the mean of systolic BP (SBP) and diastolic BP (DBP) in comparison to the nonuser group. There was a significant higher level of serum creatinine and a significant lower level of creatinine clearance in the COCPs users group as compared with the nonusers group, but non significant differences in the level of serum urea. Also there is a significant increase in the mean of MAU level of the COCPs users group in comparison to the nonusers group. There were a non significant positive correlation between SBP and MAU level and DBP and MAU level among COCPs users. There were non significant variations in the renal function tests among COCPs user group according to duration of use except that for MAU, there was a significant positive correlation between MAU and duration of usage of COCPS. Conclusion: The use of COCPs is independently a cause of a significant increase (although within normal range) of BP and MAU but non significant variations in the renal function tests among COCPs users group according to duration of usage except that for MAU, there was a significant positive correlation between MAU and duration of usage of COCPS and the changes of MAU is irrespective to the BP changes. These data suggest that the use of hormonal contraceptives (HC) may be deleterious from a renal and cardiovascular disease point of view.