Pharmacokinetics of exogenous gonadotropin and ovarian response in in vitro fertilization

Dehydroepiandrosterone supplementation and the impact of follicular fluid metabolome and cytokinome profiles in poor ovarian responders

BACKGROUND

Poor ovarian responders (POR) are women undergoing in-vitro fertilization who respond poorly to ovarian stimulation, resulting in the retrieval of lower number of oocytes, and subsequently lower pregnancy rates. The follicular fluid (FF) provides a crucial microenvironment for the proper development of follicles and oocytes through tightly controlled metabolism and cell signaling. Androgens such as dehydroepiandrosterone (DHEA) have been proposed to alter the POR follicular microenvironment, but the impact DHEA imposes on the FF metabolome and cytokine profiles is unknown. Therefore, the objective of this study is to profile and identify metabolomic changes in the FF with DHEA supplementation in POR patients.

METHODS

FF samples collected from 52 POR patients who underwent IVF with DHEA supplementation (DHEA +) and without (DHEA-; controls) were analyzed using untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) metabolomics and a large-scale multiplex suspension immunoassay covering 65 cytokines, chemokines and growth factors. Multivariate statistical modelling by partial least squares-discriminant regression (PLSR) analysis was performed for revealing metabolome-scale differences. Further, differential metabolite analysis between the two groups was performed by PLSR β-coefficient regression analysis and Student's t-test.

RESULTS

Untargeted metabolomics identified 118 FF metabolites of diverse chemistries and concentrations which spanned three orders of magnitude. They include metabolic products highly associated with ovarian function - amino acids for regulating pH and osmolarity, lipids such fatty acids and cholesterols for oocyte maturation, and glucocorticoids for ovarian steroidogenesis. Four metabolites, namely, glycerophosphocholine, linoleic acid, progesterone, and valine were significantly lower in DHEA + relative to DHEA- (p < 0.05-0.005). The area under the curves of progesterone glycerophosphocholine, linoleic acid and valine are 0.711, 0.730, 0.785 and 0.818 (p < 0.05-0.01). In DHEA + patients, progesterone positively correlated with IGF-1 (Pearson r: 0.6757, p < 0.01); glycerophosphocholine negatively correlated with AMH (Pearson r: -0.5815; p < 0.05); linoleic acid correlated with estradiol and IGF-1 (Pearson r: 0.7016 and 0.8203, respectively; p < 0.01 for both). In DHEA- patients, valine negatively correlated with serum-free testosterone (Pearson r: -0.8774; p < 0.0001). Using the large-scale immunoassay of 45 cytokines, we observed significantly lower MCP1, IFNγ, LIF and VEGF-D levels in DHEA + relative to DHEA.

CONCLUSIONS

In POR patients, DHEA supplementation altered the FF metabolome and cytokine profile. The identified four FF metabolites that significantly changed with DHEA may provide information for titrating and monitoring individual DHEA supplementation.

Amphiregulin is much more abundantly expressed than transforming growth factor-alpha and epidermal growth factor in human follicular fluid obtained from patients undergoing in vitro fertilization-embryo transfer

OBJECTIVE

To identify the most important epidermal growth factor (EGF) receptor ligand in the LH or hCG signal pathway in human ovary.

DESIGN

A retrospective clinical study.

SETTING

Tertiary university hospital.

PATIENT(S)

Ninety-eight infertile patients who underwent IVF-embryo transfer.

INTERVENTION(S)

Sera and follicular fluid were collected at the time of oocyte retrieval. The levels of EGF, transforming growth factor-alpha (TGFalpha), and amphiregulin (AR) were measured in follicular fluid and sera by using ELISA.

MAIN OUTCOME MEASURE(S)

The relationships between the level of AR and level of hCG, fertilization rate, and embryo quality.

RESULT(S)

Amphiregulin was abundantly expressed in follicular fluid after hCG stimulation. Although large differences were found between AR and both EGF and TGFalpha in follicular fluid, no significant difference was detected in the levels of the three EGF receptor ligands in sera. The level of AR was inversely correlated with the fertilization rate and hCG level, whereas little significant association was observed between the level of AR and embryo quality.

CONCLUSION(S)

Amphiregulin was expressed most dominantly among EGF receptor ligands tested and may mediate the hCG signal in human oocyte maturation. Elaborate interaction between AR and hCG may be required for an optimal oocyte maturation.

Endometrial, subendometrial, and ovarian stromal blood flow in patients treated with two different doses of recombinant human chorionic gonadotropin

The effects of two different doses of recombinant hCG on blood flow to the uterus and ovary on the day of oocyte retrieval were studied by three-dimensional Doppler ultrasonography in 60 women during IVF treatment. There were no differences in all the indices of endometrial, subendometrial, and ovarian stromal blood flow in women who had received 250 microg or 500 microg of recombinant hCG for final oocyte maturation.

Diminished intrafollicular estradiol levels in in vitro fertilization cycles from women with reduced ovarian response to recombinant human follicle-stimulating hormone

OBJECTIVE

To correlate serum and intrafollicular E(2) levels in women receiving GnRH agonist and recombinant human (h)FSH for IVF.

DESIGN

Prospective study.

SETTING

Academic IVF center.

PATIENT(S)

Twenty-three nonhirsute ovulatory women.

INTERVENTION(S)

In vitro fertilization cycles were classified as high- or low-normal response, according to whether the amount of recombinant hFSH administered was below or above, respectively, the mean recombinant hFSH given to all women combined. Serum bioactive LH and immunoreactive FSH were measured during pituitary desensitization preceding recombinant hFSH and repeated at oocyte retrieval. The first mature follicle aspirated from either ovary had a mean diameter >15 mm.

MAIN OUTCOME MEASURE(S)

Serum and follicular fluid (FF) insulin, bioactive LH, immunoreactive FSH, and steroid levels.

RESULT(S)

Basal serum gonadotropin levels were comparable between female groups. Serum immunoreactive FSH levels, but not bioactive LH levels, at oocyte retrieval were greater in cycles of low-normal vs. high-normal response, whereas maximum serum E2 levels and total oocyte counts were similar between both groups. Despite elevated FF immunoreactive FSH levels, FF E2 was decreased in low-normal response cycles. Intrafollicular T and P also were decreased and increased, respectively, in cycles of low-normal response, although FF bioactive LH levels were comparable in both groups.

CONCLUSION(S)

Intrafollicular E2 is decreased in cycles of reduced ovarian responsiveness to GnRH agonist and recombinant hFSH and is not predicted by maximal serum E2 or number of oocytes retrieved.

A poor response in the first in vitro fertilization cycle is not necessarily related to a poor prognosis in subsequent cycles

OBJECTIVE

To calculate the cumulative ongoing pregnancy rate in patients with a poor response in their first IVF cycle.

DESIGN

Retrospective cohort study.

SETTING

In vitro fertilization unit of a university hospital.

PATIENT(S)

Two hundred twenty-five women who experienced a poor response in their first IVF or intracytoplasmic sperm injection cycle. These patients were divided into 64 expected (aged > or =41 years and/or elevated FSH level) and 161 unexpected poor responders (aged <41 years and FSH level not elevated).

INTERVENTION(S)

In vitro fertilization treatment with a long-suppression protocol with FSH-urofollitropin or recombinant FSH.

MAIN OUTCOME MEASURE(S)

Cumulative ongoing pregnancy rate. This rate was calculated in two ways to correct for dropouts: pessimistic (zero chance of pregnancy for the dropouts) and optimistic (the same chance for the dropouts as for patients who continued).

RESULT(S)

The cumulative ongoing pregnancy rate of women with an unexpected poor response in the first cycle was 37% (pessimistic) to 47% (optimistic) after three cycles. Women with an expected poor response had a cumulative ongoing pregnancy rate of 16% (pessimistic) to 19% (optimistic) after 3 cycles. Sixty-four percent of the unexpected poor responders and 31% of the expected poor responders had a normal response in the second cycle, most of them after receiving a higher dose of gonadotropins.

CONCLUSION(S)

Most patients with an unexpected poor response in the first cycle had a normal response in the second cycle, leading to an acceptable cumulative ongoing pregnancy rate after three cycles. Patients with an expected poor response in the first cycle should be advised to withdraw from treatment after the first cycle because of a poor prognosis.

Unsuccessful oocyte retrieval: technical artefact or genuine 'empty follicle syndrome'?

Unsuccessful oocyte retrieval after apparently successful ovarian stimulation (also referred to as 'empty follicle syndrome') occurs in 1-7% of women undergoing assisted reproductive techniques. A literature review was performed, as individual studies have reached differing conclusions on the aetiology and treatment or management of the phenomenon. The aetiology is not clear, but probably multifactorial, and occurs in natural and stimulated cycles. In many cases, technical problems such as errors in human chorionic gonadotrophin (HCG) administration or defects in HCG batches can be identified, but this is not sufficient to account for all reported cases. The term empty follicle syndrome is inappropriate in cases in which such procedural factors can be identified. In many patients, however, unsuccessful oocyte retrieval appears to be due to an underlying ovarian dysfunction, and some may have a genuine empty follicle syndrome. Appropriate measures, such as monitoring of serum beta-HCG, should be taken to minimize the risk of unsuccessful oocyte retrieval. This review discusses the potential causes of unsuccessful oocyte retrieval, its clinical implications, and potential solutions to this clinical problem.

Subcutaneous versus intramuscular administration of human chorionic gonadotropin during an in vitro fertilization cycle

OBJECTIVE

To confirm that hCG levels in follicular fluid and serum would be comparable between i.m. and s.c. administration of purified hCG.

DESIGN

In a prospective study, serum and follicular fluid levels of hCG after an i.m. or s.c. injection of 10,000 IU of hCG were evaluated 36 hours after injection, that is, at the time of oocyte retrieval.

SETTING

This study was carried out in a university-affiliated IVF program.

PATIENT(S)

Forty women undergoing oocyte retrieval were entered into the study at the time of egg retrieval, that is, 36 hours after hCG administration.

INTERVENTION(S)

S.c. or i.m. injection of hCG.

MAIN OUTCOME MEASURE(S)

Serum and follicular fluid concentrations of hCG were evaluated 36 hours after injection at the time of oocyte retrieval.

RESULT(S)

There was a significantly higher serum hCG level in the s.c. group (348.6 +/- 98 IU/L) vs. the i.m. group (259.0 +/- 115 IU/L) and a significantly higher follicular fluid hCG level in the s.c. vs. the i.m. group (233.5 +/- 85 vs. 143.4 +/- 134 IU/L).

CONCLUSION(S)

After purified hCG administration via the s.c. route, both serum and follicular fluid levels are greater compared with the i.m. route.