Effect of combined oral contraceptive use on verbal memory function in healthy women

Female sex hormones as well as the synthetic hormones contained within combined oral contraceptives (COCs) may influence emotional and cognitive functioning including learning and memory; however, findings are inconsistent. We here present the largest study to date investigating the effect of COC use on verbal memory in healthy women.

COC use and verbal memory scores were available from the CIMBI database for 205 healthy women in the reproductive age. We assessed if verbal memory and affective bias differed between COC users and non-users. In a subgroup of natural cycling women in the follicular phase, we assessed if verbal memory was associated with plasma estradiol levels.

We found no statistically significant group differences in either overall memory performance (p = 0.16) or affective memory bias (p = 0.18) between COC users and non-users, although there was a trend suggesting COC users may exhibit slightly better recall for short-term (p = 0.09) and long-term task (p = 0.08) conditions. Similarly, COC users tended to have slightly better overall memory compared with women in the follicular phase (p = 0.05). Follicular phase plasma estradiol levels were not associated with verbal memory.

We found no support for COC use to negatively impact verbal memory, if anything COC users tended to perform better than natural cycling women in follicular phase; however, this could be influenced by a healthy user bias. In conclusion, these findings highlight that women who tolerate COCs well should not be concerned about potential adverse effects on memory.