The effect of oral contraceptive pills on the macula, the retinal nerve fiber layer, the ganglion cell layer and the choroidal thickness

BACKGROUN: To evaluate the effect of oral contraceptive pills (OCP) on the macula, the retinal nerve fiber layer (RNFL), the ganglion cell layer (GCL), and the choroidal thickness (CT). METHODS: In this prospective observational cross-sectional study, 60 eyes of 30 healthy women taking monophasic OCP (0.03 mg ethinylestradiol and 0.15 mg levonorgestrel) for contraception for at least 1 year were compared with 60 eyes of a control group of 30 healthy women who were not taking any OCP. Spectral-Domain Optical Coherence Tomography (SD-OCT) was used to evaluate the macula, the RNFL, the GCL, and the CT. Measurements were taken in the follicular phase (day 3) of the last menstrual cycle in all women. The body mass index (BMI) scores of all participants were also recorded. RESULTS: No disparity in terms of age and BMI between both groups was observed (p = 0.444, p = 0.074, respectively). All the macular parameters measurements were considerably lower in the OCP group compared to the control group (p < 0.001). Also, the RNFL thickness, the GCL thickness, and the CT were all significantly thinner in the OCP group (p < 0.001). CONCLUSIONS: The use of OCP can cause significant changes in the retina and choroid thickness over 1 year period. The women who are using OCP for a longer duration could have some eye problems. OCT should be routinely done for follow up. Further long term studies are required, using different preparations of OCP. It is important to find out when this thickness alterations can be clinically significant or symptomatic and if these changes are reversible or not.