Involvement of ovarian factors magnified by pharmacological induction of multiple follicular development (MFD) in the increase in Ca125 occurring during the luteal phase and the first 12 weeks of induced pregnancies.

Abstract

To evaluate the relationship of ovarian activity on Ca125 production, we studied whether Ca125 production varies during the menstrual cycle both in normal ovulatory women and in women whose ovarian factors are significantly stimulated by multiple follicular development (MFD). Furthermore, since the first 12 weeks of pregnancy is characterized by the enhancement of corpus luteum function mainly in MFD-induced pregnancies, Ca125 levels were also evaluated in the first quarter of pregnancy both in spontaneous and in MFD-induced pregnancies. Subjects were normal ovulatory women in the late follicular phase (FP) (N = 20) and in the luteal phase (LP) (N = 20), 32 infertile women submitted to MFD with pure FSH, and 40 pregnant women in which pregnancy occurred spontaneously (N = 20) or after induction of MFD (N = 20). In regularly cycling women plasma Ca125 levels were constant during the menstrual cycle. In contrast, in stimulated cycles Ca125 levels were significantly higher (P < 0.0008) in the LP than in the FP. In addition, in these subjects Ca125 levels in the LP were significantly correlated (P < 0.0001, r = 0.686) with E2 plasma levels. These data strongly suggest that an increase in corpus luteum function could be involved in Ca125 production. Since granulosa cells have not been demonstrated to produce Ca125, it can be hypothesized that endometrial or peritoneal cells submitted to exaggerated stimulation by ovarian activity are the source of increased Ca125 secretion. In agreement with this hypothesis, Ca125 levels were significantly higher in the first weeks of spontaneous pregnancies than in the luteal phase and they were also higher in MFD-induced pregnancies than in spontaneous pregnancies (P < 0.001).