Cytologic Features of Oocytes in the Adult Human Ovary**Supported by Grants HD-06916 and 1 PO1 HD06645 from the National Institute of Child Health and Human Development, Contract 71-2225.Reprint requests: Dr. Melvin Taymor, Peter Bent Brigham Hospital, 721 Huntington Avenue, Boston, Mass. 02115

Oocyte donation in low responders to conventional ovarian stimulation for in vitro fertilization

OBJECTIVE

To analyze endometrial response (endometrial dating and implantation) to exogenous administration of E2-valerate and P in women with low response to gonadotropins undergoing oocyte donation.

DESIGN

Prospective study. A cycle in which endometrial specimens were obtained and subsequent cycles with ET were evaluated. The control group was made up of patients with premature ovarian failure (POF) undergoing the same procedure.

SETTING, PATIENTS

In Vitro Fertilization program at the Instituto Valenciano de Infertilidad. A total of 37 women with low response to gonadotropins in previous cycles and 33 women with POF.

INTERVENTIONS

First artificial cycle with E2-valerate and P in the absence of previous pituitary suppression to determine endometrial adequacy. Successive artificial cycles in which ET was performed on cycle day 17. Oocytes donated from infertile patients undergoing IVF.

MAIN OUTCOME MEASURES

Serum steroid levels were measured during the artificial cycle. Histologic dating of the endometrium on cycle days 15 and 26. Ultrasonographically documented IVF-ET pregnancies.

RESULTS

Postovulatory changes on cycle day 15 were observed in 36.4% of low responders treated with E2-valerate and P in the absence of simultaneous pituitary suppression. Pregnancy rates were higher in women with previous sufficiently (77.8%) or insufficiently (80%) estrogen-primed endometrium than in the cases showing postovulatory changes (37.5%). Pregnancy rates (PRs) per transfer were significantly higher in low responders (63.8%) than in patients with POF (37.2%). Patients with endometriosis had a 71.4% PR per transfer. Embryos derived from oocytes from polycystic ovaries had a 48.3% PR.

CONCLUSIONS

Oocyte donation is a reliable alternative for women with low response to gonadotropins, including those with severe endometriosis. The efficacy of the steroid replacement regimen in controlling ovarian function may influence outcome. Thus, women with functional ovaries despite exogenous steroid replacement might be differently treated. Women with polycystic ovaries are an adequate source of oocyte donation.

Human antral follicles: oocyte nucleus and the karyosphere formation (electron microscopic and autoradiographic data)

The functional organization of the nucleus in the oocytes from human antral follicles was examined by morphological and autoradiographic analysis methods at the light and electron microscopic level. According to the position of the nucleus, the level of its transcriptional activity, and the pattern of distribution of structures in it, oocytes fall into two groups. In the first one, the oocytes with the nucleus in the central position are characterized by the distribution of numerous structures all over the nucleus or by a different extent of aggregation of chromatin around the nucleolus. The nuclei of these oocytes are characterized by [3H]uridine incorporation, the label being localized over purely fibrillar, agranular nucleoli and over dispersed fibrillar chromatin adjacent to either the regions of densely packed chromatin or fibrillar-granular material of the nucleolus-like bodies. The latter, the same as condensed chromatin, do not incorporate [3H]uridine. In the second group, the nuclei are displaced towards the oocyte's periphery, and chromosomes surround the nucleolus as a continuous mass closely adjacent to its surface, thus forming a karyosphere. The karyosphere formation takes place on the background of cessation of nuclear transcriptional activity. A fully formed karyosphere represents a complex of closely associated inactivated structures: Nucleolus, chromosomes, and nucleolus-like bodies. The karyosphere nucleolus bears no granules and consists of densely packed finely fibrillar material (fibrils 3 nm thick). Two zones (central and peripheral) can be distinguished in a nucleolus. Nucleolus-like bodies, consisting of granules 20 nm in diameter embedded in finely fibrillar material, are often associated with chromosomes. In this study, data obtained by observations on the loss of association between the oocyte (with karyosphere) and corona radiata cells are evaluated. The relation of the karyosphere formation to the atresia process and the duration of karyosphere existence in human antral follicles are also discussed.

Influences of dehydroepiandrosterone acetate on ovarian oocytes in mature cycling rats

Degeneration of ovarian oocytes occurred to a remarkable extent in rats with polycystic ovaries induced by dehydroepiandrosterone acetate (DHA-Ac) administration. The ratio of degeneration oocytes, compared with the total oocytes examined, finally exceeded 70%.

Recovery of midcycle human follicular oocytes: correlation of their morphology with endomethrial and follicular histology

The ovarian follicles of 23 of 33 women undergoing elective pelvic laparotomy during menstrual cycle days 11 to 17 were aspirated by a low-vacuum device. The study compared the ovulatory status of women in midcycle with the health of the oocytes obtained, and determined the frequency of recovery of mature oocytes without the preadministration of exogenous hormones. Maturing or mature oocytes were obtained from 22% and nonmature oocytes from 48% of the 23 women. Sixty per cent of the women in each of the maturing or mature and nonmature groups were postovulatory as judged by evaluation of the endometrial and ovarian tissue recovered. Furthermore, 20% of the maturing or mature oocytes and 65% of the nonmature oocytes showed a moderately heavy amount of cytoplasmic degeneration, which was independent of ovulatory status. Therefore, it is concluded that, because of the relatively low rate of return of oocytes, the frequent postovulatory status of patients in midcycle, and uncertainty about the viability of the oocytes so obtained, women not stimulated by exogenous hormones are ill-suited for recovery of maturing or mature follicular oocytes for in vitro fertilization studies.