The utility of serum progesterone and inhibin A for monitoring natural-cycle IVF-ET

Purpose: Our purpose was to assess the value of monitoring serum P and inhibin A to determine how values might improve the clinical monitoring of natural cycle in vitro fertilization (IVF)-embryo transfer (ET) patients. Methods: All patients(n = 26) who underwent natural-cycle IVF-ET (n = 35) were analyzed. Groups were evaluated according to patients who had a spontaneous luteinizing hormone (LH) surge (group I) and women receiving human chorionic gonadotropin (hCG) who underwent subsequent oocyte aspiration (group II). Group II was further evaluated according to women who did (n = 10) and did not (n = 7) have an ET. All cycles were evaluated with serial transvaginal ultrasonography and serum estradiol, progesterone, and inhibin A. When follicle maturity was achieved, hCG, 10.000 IU, was administered intramuscularly if a LH surge was not detected. Transvaginal ultrasound-guided aspiration was performed 34-36 hr after hCG administration followed by a 48-hr transcervical ET. Results: No differences were seen in cycles the day prior to (d-1) and the day of a spontaneous LH surge, (n = 18) or hCG (d-0)(n = 17) in group I or group II with respect to lead follicular diameter (d-1, 15.3 +/- 0.6 vs. 14.2 +/- 0.9 mm; d-0, 17.4 +/- 0.8 vs, 17.8 +/- 0.6 mm) and serum estradiol (d-1, 148 +/- 15 vs, 150 +/- 15 pg/ml; d-0, 218 +/- 15 vs. 199 +/- 16 pg/ml), respectively. However; serum progesterone was significantly elevated in group I compared with group II on d-1 (0.82 +/- 0.6 vs. 0.48 +/- 0.04 ng/ml; P < 0.05) and d-0 (1.1 +/- 0.12 vs. 0.63 +/- 0.08 ng/ml; P < 0.05). Inhibin A was significantly greater on d-1 in group I (24 +/- 2.5 vs. 15 +/- 2.2 pg/ml; P < 0.05). In group II. cycles that resulted in an ET (n = 10) compared with group II cycles that did not (n = 7) revealed a significant difference in serum progesterone (0.51 +/- 0.05 vs. 0.7 +/- 0.07 ng/ml; P < 0.05) and inhibin A (15 +/- 2.5 vs. 37.3 +/- 5 pg/ml: P < 0.05) the day of hCG. Conclusions: The possible application of serum progesterone and inhibin A in managing natural-cycle IVF-ET is suggested. These assays may predict women who should be set up for egg retrieval, while canceling others in spite of the absence of an LH surge.