ACUTE CHANGES IN ENDOMETRIAL THICKNESS AFTER ASPIRATION OF FUNCTIONALOVARIAN CYSTS

Objective: To evaluate the influence of aspiration of functional ovari an cysts on endometrial thickness. Design: Prospective study. Setting: An IVF Unit of an academic medical center. Patient(s): Twenty-two pat ients from our IVF program, in whom administration of a gonadotropin-r eleasing hormone agonist preparation in the ''long protocol'' failed t o induce pituitary desensitization, as evidenced by a serum E-2 concen tration of >55 pg/mL and the presence of an ovarian cyst of >20 mm in diameter. Intervention(s): Transvaginal ultrasonographic-guided cyst a spiration was performed, and 2 days later, serum E, concentration and endometrial thickness were reassessed. Main Outcome Measure(s): The va lues of serum E, concentration and endometrial thickness before and af ter cyst aspiration were compared. Result(s): Two days after ovarian c yst aspiration, the serum E-2 concentration dropped from a mean (+/-SD ) of 203 +/- 93 to 37 +/- 34 pg/mL. The mean (CSD) endometrial thickne ss was 9.6 +/- 2.0 mm before cyst aspiration and decreased to 5.9 +/- 2.4 mm after the procedure. Conclusion(s): Within 48 hours after ovari an cyst aspiration, a significant reduction in endometrial thickness o ccurs concomitant with a sharp decline in serum E, levels. The phenome non of acute reduction in endometrial thickness in response to acute e strogen withdrawal has not been described previously. The exact mechan ism and endometrial component involved in the ''shrinking'' process sh ould be further investigated. (C)1998 by American Society for Reproduc tive Medicine.