Total protein, IgG, secretory IgA (SIgA), IgA, IgM, and albumin were quantitatively analyzed in 115 cervical fluid specimens from healthy, adult women. Although albumin was the most predominant protein among those that were analyzed (17.2% of total protein), IgG was the major immunoglobulin in this secretion (8.7%). A highly significant correlation between the levels of IgG and albumin and a mean IgG-albumin ratio similar to that of serum suggest that both proteins originate from the circulation. Although the main type of IgA was of the secretory type (4.4%), serum type IgA (smaller than 1.0%) was close to 2. The mean levels of IgG and albumin (but not of SIgA) of the postpartum group were significantly higher than those of the normal subjects. The number of children, the current method of contraception, and present and past local infections had no effect on the immunoglobulins and albumin in this secretion when the mean levels of these components were analyzed and compared with the "normal" values.