Effect of phases of the menstrual cycle on biophysical and biochemical parameters of African black women with breast cancer

Abstract

INTRODUCTION: Many studies on female breast cancer patients do not consider the differences between the follicular and luteal phases when collecting blood samples for laboratory investigations. Therefore, this study was designed to investigate the effects of the phases of the menstrual cycle on reproductive and thyroid hormones, endocrine disruptors, blood pressure, and body adiposity. METHODS: Participants (n=107) aged 28-50 years, comprising 54 newly diagnosed breast cancer patients (cases were menstrual phase and age-matched to 53 seemingly healthy women without breast cancer that served as controls. Anthropometric indices and blood pressure (BP) were obtained. Serum hormones-estradiol, progesterone, luteinizing hormone (LH), free triiodothyronine (FT3), thyroid-stimulating hormone (TSH), stimulating follicle hormone (FSH), and free thyroxine (FT4) were quantified by enzyme immunoassay. Endocrine disruptors (EDs)- arsenic, lead and cadmium were quantified by atomic absorption spectrophotometry (AAS). Data were analyzed using Student’s t-test and Pearson correlation coefficient with p<0.05 considered significant. RESULTS: Bodyweight, hip circumference, waist-height ratio, and FT3 varied between the luteal and follicular phases, higher in cases than controls. EDs were significantly higher in cases than controls in both phases. Progesterone, estradiol and LH levels were significantly higher in luteal cases and controls when compared with follicular cases and controls.FT3 was significantly lower in luteal controls compared with follicular controls. There were significant direct and inverse correlations among adiposity measures, BP, EDs, and hormones in each phase in both cases and controls. CONCLUSION: The menstrual cycle appears to influence blood pressure, measures of adiposity, endocrine disruptors, and reproductive hormones in women with normal and cancerous breasts. This requires consideration in the collection of blood samples for investigations of these parameters.