Variability between the follicular steroid hormone levels in different follicles of the same patient and between patients

Effect of letrozole on follicular fluid steroids concentrations in cancer patients undergoing oocytes cryopreservation

PURPOSE

To investigate the impact of letrozole administration on follicular steroid hormones during controlled ovarian hyperstimulation for fertility preservation.

METHODS

One hundred and nineteen women with cancer undergoing oocytes retrieval for fertility preservation were recruited. All women underwent ovarian hyperstimulation according to a random start protocol. Those with hormone-sensitive tumors also received letrozole, an aromatase inhibitor aimed at keeping peripheral estrogen levels low. At the time of oocytes retrieval, a sample of follicular fluid was collected and frozen. All samples were assayed concomitantly after thawing, by liquid chromatography tandem mass spectrometry. The concentration of 15 steroid hormones was determined and results were compared between women who did and did not receive letrozole.

RESULTS

Fifty-two women were treated with letrozole, while 67 were not. Statistically significant differences emerged for 12 of the 15 tested steroids. They were the following: cortisol, 11-deoxycortisol, 21-deoxycortisol, dehydroepiandrosterone sulfate (DHEAS), dehydroepiandrosterone (DHEA), estradiol, androstenedione, testosterone, dihydrotestosterone (DHT), 17-hydroxyprogesterone, progesterone and corticosterone. The most striking differences were observed for testosterone that showed a more than 200-time increase in women receiving letrozole. Estradiol was conversely reduced to a third.

CONCLUSIONS

The endocrine microenvironment surrounding oocytes is markedly perturbed by the concomitant assumption of letrozole. Robust clinical evaluation is pressingly needed to rule out any detrimental effect on the chance of live birth with the use of these oocytes.

LH supplementation of ovarian stimulation protocols influences follicular fluid steroid composition contributing to the improvement of ovarian response in poor responder women

In this prospective study, we evaluated the steroid levels in 111 follicular fluids (FF) collected from 13 women stimulated with FSH monotherapy and 205 FF collected from 28 women stimulated with FSH + LH because of a previous history of hypo-responsiveness to FSH. Steroid levels were measured by HPLC/MS–MS and related to ovarian stimulation protocol, oocyte maturity, fertilization and quality of blastocysts, after individually tracking the fate of all retrieved oocytes. 17-Hydroxy-Progesterone, Androstenedione, Estradiol and Estrone were significantly higher in the FSH + LH protocol. Progesterone, 17-Hydroxy-Progesterone and Estradiol were more expressed in FF yielding a mature oocyte (p < 0.01) in the FSH + LH protocol. FF Progesterone concentration was correlated with the rate of normal fertilization in the FSH protocol. None of the FF steroids measured were associated with blastocyst quality and achievement of pregnancy. Our results indicate that LH supplementation in hypo-responsive women modifies ovarian steroid production, mimicking physiological production better and likely contributing to an improved ovarian response. Employing a correct methodological procedure to evaluate the relationship between FF steroid hormones and assisted reproduction outcomes, our study reveals that some steroids in single follicles may be helpful in predicting oocyte maturity and fertilization.

In ovaries with high or low variation in follicle size, granulosa cells of antral follicles exhibit distinct size-related processes

Antral follicle size might be a valuable additive predictive marker for IVF outcome. To better understand consequences of antral follicle size as a marker for reproductive outcome, we aimed to obtain insight in follicle size-related granulosa cell processes, as granulosa cells play an essential role in follicular development via the production of growth factors, steroids and metabolic intermediates. Using the pig as a model, we compared gene expression in granulosa cells of smaller and larger follicles in the healthy antral follicle pool of sows, which had a high variation versus low variation in follicle size. Selected gene expression was confirmed at the protein level. Granulosa cells of smaller antral follicles showed increased cell proliferation, which was accompanied by a metabolic shift towards aerobic glycolysis (i.e. the Warburg effect), similar to other highly proliferating cells. High granulosa cell proliferation rates in smaller follicles might be regulated via increased granulosa cell expression of the androgen receptor and the epidermal growth factor receptor, which are activated in response to locally produced mitogens. While granulosa cells of smaller follicles in the pool are more proliferative, granulosa cells of larger follicles express more maturation markers such as insulin-like growth factor-1 (IGF1) and angiopoietin 1 (ANGPT1) and are therefore more differentiated. As both higher IGF1 and ANGPT1 have been associated with better IVF outcomes, the results of our study imply that including smaller follicles for oocyte aspiration might have negative consequences for IVF outcome.

Letrozole-associated controlled ovarian hyperstimulation in breast cancer patients versus conventional controlled ovarian hyperstimulation in infertile patients: assessment of oocyte quality related biomarkers

BACKGROUND

Fertility preservation (FP) protocols in case of breast cancer (BC) include mature oocyte cryopreservation following letrozole associated controlled ovarian hyperstimulation (Let-COH). To date, the impact of Let-COH on the follicular microenvironment has been poorly investigated, although a high androgen/estrogen ratio was previously associated with low oocyte quality.

METHODS

In this prospective study, follicular fluid (FF) steroid levels (estradiol, testosterone, progesterone) and cumulus cell (CC) gene expression related to oocyte quality (HAS2, PTGS2, GREM1) were compared between 23 BC patients undergoing Let-COH for FP and 24 infertile patients undergoing conventional COH without letrozole. All patients underwent an antagonist COH cycle, and ovulation was triggered with hCG or GnRHa in both groups.

RESULTS

FF estradiol levels were significantly lower while testosterone levels were significantly higher in the study group compared to controls irrespective of the trigger method. However, estradiol levels increased significantly with GnRHa triggering compared to hCG in the study group (median = 194.5 (95.4-438) vs 64.4 (43.8-152.4) ng/ml, respectively, p < 0.001), but not in the control group (median = 335.5 (177.5-466.7) vs 354 (179-511) ng/ml, respectively). After hCG trigger, Cumulus cell (CC) gene expression was lower in the study group compared to the control group, and difference was significant for PTGS2. Conversely, CC gene expression of PTGS2 and GREM1 was significantly higher in the study group compared to controls when ovulation was triggered with GnRHa.

CONCLUSIONS

Let-COH triggered with hCG may negatively impact oocyte quality. However, ovulation triggering with GnRHa may improve the oocyte microenvironment and cumulus cell genes expression in Let-COH, suggesting a positive impact on oocyte quality in breast cancer patients.

TRIAL REGISTRATION

Clinicaltrials.gov - NCT02661932 , registered 25 January 2016, retrospectively registered.