Oral contraceptive hormones, folate metabolism, and the cervical epithelium.

The currently available evidence concerning disorders of folate metabolism in women taking oral contraceptives has been reviewed. A disturbance in folate balance serious enough to cause symptoms (i.e., megaloblastic anemia) occurs very rarely. In some series, but not in others, serum and/or red cell folate concentrations have been reduced in oral contraceptive users. It is doubtful whether sex steroids affect polyglutamate folate absorption. About 20 percent of women taking contraceptive hormones manifest mild megaloblastic changes on Papanicolaou smears of the cervicovaginal epithelium which disappear after folic acid therapy. The current evidence, however, would not indicate that any significant benefit would ensue from routine folate supplementation in women on oral contraceptives.