Effect of oral contraceptives on depressive mood changes and on endometrial monoamine oxidase and phosphatases.

Significant variations in the incidence of depression and loss of libido were found with the various types of oral contraceptives. The highest incidence occurred with strongly progestogenic compounds (especially with those containing a small amount of oestrogen) which have high monoamine oxidase activity for most of the cycle. The lowest incidence was found with the strongly oestrogenic sequential regimens which have weak monoamine oxidase activity for most of the cycle.