The Ovarian Sensitivity Index (OSI) Significantly Correlates with Ovarian Reserve Biomarkers, Is More Predictive of Clinical Pregnancy than the Total Number of Oocytes, and Is Consistent in Consecutive IVF Cycles

Abstract

Background and Objectives: Some biomarkers of ovarian responsiveness to gonadotropins and the total number of retrieved oocytes are known to affect the success rate after controlled ovarian stimulation (COS) and in vitro fertilization (IVF). The aim of this study was to study another putative marker, the Ovarian Sensitivity Index (OSI: (number of retrieved oocytes/total gonadotropin dose) × 1000), assessing whether (a) it correlates with ovarian responsiveness biomarkers, (b) it is an independent predictor of clinical pregnancy, (c) it predicts clinical pregnancy comparably to the number of retrieved oocytes, and (d) it is consistent in the repeated COS cycles of the same woman. Design: retrospective analysis. Setting: public IVF Unit in University Hospital. Cases and Measurements: 1612 patients submitted to 3353 IVF cycles were included, their OSI was calculated and it was correlated with the ovarian responsiveness biomarkers (age, BMI, anti-Mullerian hormone, antral follicle count). The OSI and the total number of oocytes were compared for their value in predicting clinical pregnancy. The inter-cycle consistency of the OSI was estimated in 209 patients who underwent two consecutive cycles in which the ovarian stimulation regimen was changed from the Gonadotropin-releasing Hormone (GnRH)-agonist long protocol to the GnRH-antagonist protocol or vice-versa. Results: The OSI turned out to be significantly related to age and BMI (inversely), the anti-Mullerian hormone (AMH) and the antral follicle count (AFC) (directly), to be an independent predictor of clinical pregnancy, and to correlate with clinical pregnancy better than the total number of oocytes (p < 0.0001 vs. <0.002). In patients who underwent two consecutive COS cycles changing stimulation regimen, the OSI showed 82% consistency. Conclusion(s): The OSI significantly correlates to the currently used biomarkers of ovarian responsiveness; it is an independent predictor of clinical pregnancy; it is more predictive of clinical pregnancy than the total number of oocytes, and is highly consistent in repeated IVF cycles even when the COS protocol changes. These characteristics make the OSI quite suitable to be incorporated into more complex prediction models of IVF outcome.

Luteal Support with very Low Daily Dose of Human Chorionic Gonadotropin after Fresh Embryo Transfer as an Alternative to Cycle Segmentation for High Responders Patients Undergoing Gonadotropin-Releasing Hormone Agonist-Triggered IVF

“…Embryos that progressed to the expanded blastocyst stage on day 5 (score 3) showed compacted inner cell mass (score 1), and cohesive trophoectoderm (score 1 or 2) were selected for the first transfer in both groups. The ET was performed as previously described [ 42 ].…”

Does Ovarian Endometriosis Increase Oocyte Sensitivity to ICSI-Induced Mechanical Damage?

“…The following variables were collected for all enrolled patients: age, duration of infertility, BMI, basal AMH, AFC, smoke habit. For all ART treatment cycles, the following variables were registered: type of pituitary suppression (GnRH agonist or antagonist), total FSH dose, serum peak estradiol (E2), number of retrieved oocytes, Ovarian Sensitivity Index (OSI = number of retrieved oocytes/total FSH dose × 1000 [17]), number of mature (MII) oocytes, number of fertilized (2PN) oocytes, number of available embryos, proportion of top-quality embryos (IMCS score > 8/10).…”

The effects of multiple controlled ovarian hyperstimulation over a 2-year period on ovarian reserve and reactivity: a retrospective clinical study

“…During COH, the extra-physiological dose of GN can promote the growth and development of other follicles, avoid the occurrence of follicular atresia, and stimulate multiple oocytes. Some studies have shown that FSH stimulation at super-physiological doses may promote the growth of the remaining follicles in the follicular pool and contribute to the recruited antral follicles, thus accelerating the depletion of the follicular pool (7). In addition, it has been reported that repeated vaginal puncture of the ovary may lead to the release of ovarian autoantigens, resulting in a decrease in the number of follicles in the follicular pool (8).…”

“…In IVF treatment, most patients will receive large doses of GN stimulation and be subjected to repeated surgery for egg harvesting. Whether these treatments have a negative effect on ovarian reserve and responsiveness remains controversial (7,13,14).…”