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Pieces of ovarian cortical tissue (0.3-2 mm in diameter) were obtained during gynaecological operations by biopsy or as a result of oophorectomy from 19 women aged 19-44 years. The tissue was frozen in a programmable freezer using one of two different cryoprotectants, either 1.5 M dimethylsulphoxide (DMSO), or a combination of 1,2-propanediol (1.5 M) and sucrose (0.1 M). After cryopreservation lasting from 24 h to 5 weeks, the ovarian pieces were thawed and studied histologically. Specimens taken before and after cryopreservation with either protectant showed no signs of tissue necrosis. Follicles at similar developmental stages were found before and after freezing. The proportions of follicles showing signs of atresia, 27% in the non-frozen tissue and 19% in the frozen-thawed tissue, were not significantly different. Oocytes, too, had the same appearance after freezing and thawing with both cryoprotectants as was seen in the specimens taken before freezing. These results suggest that cryopreservation of human ovarian tissue is feasible. However, the normality of the oocytes taken from tissue which has been frozen still needs to be established. Cryopreservation of ovarian tissue would be potentially an excellent method for storage of human oocytes once methods for their maturation in vitro have been developed.

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In-vitro maturation (IVM) of human ovarian follicles and oocytes could benefit infertile women, and allow the development of in-vitro systems for the study of human follicular development. Little is known about the initiation of growth of primordial follicles and the regulation of early folliculogenesis. An ovarian tissue-slice culture system was used to examine the effects of media composition, follicle stimulating hormone (FSH) and serum substitution on the development of small human follicles in vitro. Human ovarian cortex biopsies were cut into small pieces and cultured for 5, 10 or 15 days. Control (non-cultured) and cultured tissue was fixed, serially sectioned, and stained. The follicles contained within the tissue pieces were counted, measured, and assessed for stage of development and viability. Comparison of the ability of alpha-minimum essential medium (alpha-MEM), Waymouth's, or Earle's balanced salt solution (EBSS) culture media (all with 10% human serum) to support follicle growth demonstrated significantly increased initiation and growth of follicles in alpha-MEM during the first 10 days of culture. The supplementation of alpha-MEM with 300 mIU/ml FSH significantly reduced levels of atresia and increased the mean diameter of healthy follicles. Follicles in tissue cultured for 10 days with human serum albumin and ITS (insulin/transferrin/selenium mix) were significantly larger, more developed and showed significantly less atresia than those cultured with serum alone. Primordial to small preantral follicles can be grown under serum-substituted conditions in tissue-slice culture, and are responsive to FSH, which is thought to be acting mainly as a survival factor at these early stages.

The study tests the hypothesis that small ovaries measured on transvaginal sonography (TVS) are associated with a poor response to ovulation induction by human menopausal gonadotrophin (HMG) for in-vitro fertilization (IVF). A total of 140 infertile patients with morphologically normal ovaries undergoing IVF was studied. The mean ovarian volume of each patient was measured on TVS before starting HMG. Subsequent routine IVF management was conducted without knowledge of the results of TVS. The mean ovarian volume was 6.3 cm3 (range 0.5-18.9, SD= 3.1). Patients (n = 17; group A) with small ovaries of < 3 cm3 (i.e. overall mean volume - 1 SD) were compared to patients (n = 123; group B) with ovaries > or = 3 cm3. Both groups were of similar age (mean 35.8 versus 34.4 years). Early basal FSH concentrations were increased in group A (9.5 versus 7.0 mIU/ml, P = 0.025). The cycle was abandoned before planned oocyte recovery in nine patients (52.8%) from group A and in 11 patients (8.9%) from group B because of poor response to ovulation induction (P < 0.001). Increased age and ovarian volume were associated independently with cancellation of the cycles. The remaining eight patients from group A who had oocytes retrieved required higher doses of HMG (87.5 versus 53.8 ampoules, P < 0.01), yielded fewer follicles (10.3 versus 14.5, P < 0.05) and fewer oocytes were recovered from them (6.8 versus 11.0, P < 0.05) compared with group B. There was no difference in the fertilization or pregnancy rates or the number of embryos available for transfer in either group. Our results indicate a strong association between ovarian volume and ovarian reserve. Small ovaries are associated with poor response to HMG and a very high cancellation rate during IVF. Assessment of ovarian size should be an integral part of infertility evaluation.

Granulosa-lutein cells from women with anovPCOS are relatively resistant to the effects of insulin-stimulated glucose uptake and utilization compared with those from normal and ovPCO, whilst maintaining normal steroidogenic output in response to physiological doses of insulin. These studies support the probability of a post-receptor, signalling pathway-specific impairment of insulin action in PCOS.

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The ageing ovary appears to be characterized by depletion of primordial follicles. The relationship between infertility and the number of follicles in the ovarian cortex is not known. Moreover, there are no accurate markers or clinical methods to predict the decline in ovarian reserve. This study investigates the correlation between early follicular follicle stimulating hormone, ovarian size and follicular density in 60 infertile women aged 19-45 years (mean = 34.4 +/- 5.5). An ovarian biopsy was taken from each patient while performing diagnostic laparoscopy (n = 28) or laparotomy for tubal surgery or myomectomy (n = 32). The median number of follicles was similar in tubal and unexplained infertility patients (9.5 versus 5.5). Increasing age showed a significant negative correlation with follicular density and ovarian volume (r = -0.46, P = 0.0003;. r = -0.43, P = 0.0016, respectively). In women > or = 35 years of age the ovarian volume showed a strong correlation with follicular density (r = 0.71, P < 0.0001). Our results indicate that infertile women in their late thirties and over have a decreased ovarian reserve which could possibly be predicted by ovarian volume measurement. Ovarian biopsy may have a place as part of infertility evaluation in older women.