Objective. The objective of this analysis was to describe patterns and determinants of cervical immunoglobulin A (IgA) and G (IgG) levels during the menstrual cycle.

Methods. A total of 154 women who attended 3 visits coinciding with the follicular, periovulatory, and luteal phases of their menstrual cycle were studied. Cervical secretions were collected at each visit for determination of total IgA and IgG levels. Questionnaires administered at each visit inquired about demographic characteristics and behavioral practices.

Results. Total IgA and IgG levels were higher among oral contraceptive (OC) users than among naturally cycling women (hereafter, “non-OC users”). IgA and IgG levels decreased at midcycle, particularly among non-OC users. After adjustment for phase of the current cycle, specimen weight, and detection of blood in the sample, report of a recent illness was associated with lower IgA and IgG levels and increased age with higher IgA and IgG levels amongOC users and non-OC users. Increased lifetime number of pregnancies was associated with a higher IgA level among non-OC users and a higher IgG level amongOCusers. Change in immunoglobulin levels between visits was associated with sample weight and the presence of blood for both OC users and non-OC users.

Conclusions. Phase of the current menstrual cycle and OC use were significant determinants of cervical IgA and IgG levels. The impacts of endogenous and exogenous hormones on cervical immunoglobulin levels should be further investigated.