Follicular fluid renin concentration in patients with polycystic ovaries treated with gonadotrophins in an in vitro fertilisation programme

[Quality of oocytes and embryos from women with polycystic ovaries syndrome: State of the art]

The frequency of polycystic ovary syndrome (PCOS) and the consequent fertility disorders cause many difficulties in the management of the assisted reproductive technics. Some studies are focused on different additional treatments, stimulation protocols or techniques that could optimize the in vitro fertilization cycles. The quality of the oocytes and embryos of these patients is also an outstanding issue. They remain difficult to actually evaluate during management, and none of the few published studies on this subject demonstrated any inferiority, compared to control patients. However, many differences have been highlighted, studying intra- and extra-ovarian factors. The advent of new genetic techniques could allow a better understanding of the pathophysiological mechanisms of the syndrome, as well as refining the evaluation of oocytes and embryos, in order to better predict the results of in vitro fertilization attempts. Pregnancy and birth rates, however, appear to be comparable to those of the general population.

Extra- and intra-ovarian factors in polycystic ovary syndrome: impact on oocyte maturation and embryo developmental competence

BACKGROUND

Polycystic ovary syndrome (PCOS) is a common metabolic dysfunction and heterogeneous endocrine disorder in women of reproductive age. Although patients with PCOS are typically characterized by increased numbers of oocytes retrieved during IVF, they are often of poor quality, leading to lower fertilization, cleavage and implantation rates, and a higher miscarriage rate.

METHODS

For this review, we searched the database MEDLINE (1950 to January 2010) and Google for all full texts and/or abstract articles published in English with content related to oocyte maturation and embryo developmental competence.

RESULTS

The search showed that alteration of many factors may directly or indirectly impair the competence of maturating oocytes through endocrine and local paracrine/autocrine actions, resulting in a lower pregnancy rate in patients with PCOS. The extra-ovarian factors identified included gonadotrophins, hyperandrogenemia and hyperinsulinemia, although intra-ovarian factors included members of the epidermal, fibroblast, insulin-like and neurotrophin families of growth factors, as well as the cytokines.

CONCLUSIONS

Any abnormality in the extra- and/or intra-ovarian factors may negatively affect the granulosa cell-oocyte interaction, oocyte maturation and potential embryonic developmental competence, contributing to unsuccessful outcomes for patients with PCOS who are undergoing assisted reproduction.

No association between the microsatellite polymorphism (TTTTA)n in the promoter of the CYP11A gene and ovarian hyperstimulation syndrome

PURPOSE

Women with ultrasonic evidence of polycystic ovaries are at higher risk of ovarian hyperstimulation syndrome (OHSS). We focused on investigating a possible association of the (TTTTA)(n) microsatellite polymorphism in the promoter of the CYP11A gene with OHSS during controlled ovarian hyperstimulation (COH).

METHODS

We evaluated 58 patients at high risk of OHSS (study group) and 58 control patients undergoing controlled ovarian hyperstimulation.

RESULTS

The difference in the allele distribution between both groups of patients was not statistically significant. The genotype distribution of 4+ (with at least one copy of the four-repeat-unit allele) and 4- (without the four-repeat-unit allele) genotypes was identical in the two groups.

CONCLUSION

An association between the (TTTTA)(n) microsatellite polymorphism in the promoter of the CYP11A gene and the pathogenesis of OHSS could not be confirmed.

Prolonged HCG action affects angiogenic substances and improves follicular maturation, oocyte quality and fertilization competence in patients with polycystic ovarian syndrome

BACKGROUND

The aim of this study was to determine whether, in polycystic ovarian syndrome (PCOS) patients, HCG action prolonged for 4 h improves the action of angiogenic substances [ovarian renin angiotensin system and vascular endothelial growth factor (VEGF)], and consequently follicular maturation, oocyte quality and oocyte fertilization competence.

METHODS

In this prospective study 20 patients with PCOS undergoing IVF were included. Oocyte retrieval was carried out either 34 or 38 h after HCG administration. Each follicle was analysed for prorenin, active renin, VEGF and estradiol. Oocytes were evaluated for quality (mature, immature, degenerated oocytes), as were the embryos (low or high).

RESULTS

In the HCG +38 h group there were 245 follicles, and in the HCG +34 h group 240 follicles. In the HCG +38 h group, log active renin was lower (2.78 +/- 0.20 versus 2.91 +/- 0.25; P < 0.001) and VEGF higher (2276.0 +/- 790.1 versus 1946.6 +/- 954.5 pg/ml; P < 0.001). The odds ratio for obtaining oocytes from follicles was 1.6 [95% confidence interval (CI) 1.1-2.6; P = 0.02], and for developing high quality embryos 7.6 (95% CI 2.8-20.9; P < 0.001) in favour of the HCG +38 h group.

CONCLUSIONS

Follicular maturation and oocyte quality are related to the intrafollicular influences of active renin and VEGF in a time-dependent manner after HCG administration, whereas fertilization competence is related to VEGF only.