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R Margara

Publications and source records attributed to R Margara.

35 records · Page 2Linked to original sources
PubMed1997

Measurement of ovarian volume by transvaginal sonography before ovulation induction with human menopausal gonadotrophin for in-vitro fertilization can predict poor response.

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.

Adult↗
PubMed1997

Women with one ovary have decreased response to GnRHa/HMG ovulation protocol in IVF but the same pregnancy rate as women with two ovaries.

The study compares the response after gonadotrophin-releasing hormone agonist (GnRHa) and human menopausal gonadotrophin (HMG) stimulation for in-vitro fertilization (IVF) in patients with either one or two ovaries. The study group (group A) included 73 cycles in women who had unilateral oophorectomy before their IVF treatment and the control group (group B) included 988 cycles in women with two ovaries. Tubal disease was the sole cause for infertility in all cases. The two groups were similar in age and parity. The patients with one ovary required more ampoules of HMG (62.9 versus 48.9, P < 0.001), a longer induction period (13.5 versus 12.7, P < 0.01) and had significantly lower oestradiol concentrations on the day of human chorionic gonadotrophin (HCG) administration (5840 versus 6473 pmol/l, P = 0.035). They yielded fewer follicles (11.2 versus 13.1, P = 0.005), fewer oocytes (7.3 versus 9.1, P = 0.006) and produced fewer embryos (4.4 versus 5.1, P < 0.05). There was no difference in fertilization rate (60 compared with 58%), or pregnancy rate (25.8 compared with 27.1% per oocyte retrieval). Women with only one ovary responded less well to GnRH agonist/HMG stimulation than women who had both ovaries but pregnancy outcome was the same in both groups.

Adult↗
PubMed1997

Follicular density in ovarian biopsy of infertile women: a novel method to assess ovarian reserve.

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.

Adult↗
PubMed1997

Right or left ovary--which one is better?

This study tests the hypothesis that there is a different response after gonadotrophin-releasing hormone and human menopausal gonadotrophins (GnRH/HMG) stimulation for in-vitro fertilization (IVF) in patients with either a right or left ovary. A total of 56 cycles in 44 women after left oophorectomy (group A) was compared with 42 cycles in 29 women following right oophorectomy (group B). Tubal disease was the sole cause of infertility in all cases. The two groups were similar in age. There was no difference in total amount or days of HMG required for ovulation induction, peak oestradiol concentrations, number of oocytes retrieved and fertilization rate. The pregnancy rate was identical in the two groups (20.0 and 20.9% respectively). Our results indicate that with GnRH/HMG ovulation induction protocol for IVF there is no predilection of one ovary over the other.

Adult↗
PubMed1996

Cryopreservation of human ovarian tissue using dimethylsulphoxide and propanediol-sucrose as cryoprotectants.

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.

Adult↗
PubMed1995

Results of IVF in patients with endometriosis: the severity of the disease does not affect outcome, or the incidence of miscarriage.

The literature suggests that the results of in-vitro fertilization (IVF) for patients with endometriosis depend on the stage of the disease, and that patients with severe endometriosis have a higher failure rate. Miscarriage is said to be more prevalent in women treated for endometriosis. In the study reported here, 140 patients with endometriosis underwent 182 cycles of IVF using gonadotrophin-releasing hormone analogues (GnRHa). Patients with endometriosis only were allocated to one group (group 4). The results were compared with those of three other groups of patients undergoing the same treatment within the same period. Group 1 consisted of couples with male factor only (45 cycles), group 2, couples with unexplained infertility (196 cycles) and group 3, couples with a tubal factor only (1139 cycles). The mean age of the patients, mean number of human menopausal gonadotrophin (HMG) ampoules administered, oestradiol concentration on the day of human chorionic gonadotrophin administration, number of days of HMG, mean number of oocytes retrieved and retrieval rate were not significantly different. The fertilization rate was significantly lower in group 1; no difference was observed in the other three groups. The mean number of normally fertilized embryos was not significantly different. The number of transferred embryos in each cycle and the implantation rates were similar in the four groups. The overall pregnancy rate per transfer was 39% in group 1, 48% in group 2, 45% in group 3 and 40% in group 4.(ABSTRACT TRUNCATED AT 250 WORDS)

Abortion, Spontaneous↗
PubMed1994

Estradiol production by granulosa cells of normal and polycystic ovaries: relationship to menstrual cycle history and concentrations of gonadotropins and sex steroids in follicular fluid.

The underlying cause of anovulation in polycystic ovary syndrome is unknown. Circulating levels of immuno- and bioactive FSH are within the normal range, and the follicles contain measurable levels of bioactive FSH. The aim of this study was to compare estradiol (E2) production in response to FSH by granulosa cells from normal ovaries with those from polycystic ovaries derived from both anovulatory (anovPCO) and ovulatory subjects (ovPCO). Intrafollicular levels of immunoactive FSH, E2, and androstenedione in follicles of less than 12 mm were also measured. Follicular fluid steroid concentrations were obtained from 41 pairs of normal ovaries and 23 pairs of polycystic ovaries (8 anovPCO and 15 ovPCO). In size-matched follicles from each group there were no significant differences in follicular fluid FSH or E2 concentrations, but androstenedione levels were significantly higher in 5- to 11-mm follicles from ovPCO than in corresponding follicles from normal ovaries. Dose responses to FSH were determined in granulosa cells derived from 9 pairs of normal ovaries, 7 anovPCO, and 8 ovPCO. Cells from anovPCO produced 6- to 10-fold more E2 in response to FSH than normal cells, although there was no significant difference in the ED50 values. The response in cells from ovPCO was reduced compared to normal, but this difference did not reach significance. In summary, as judged by their FSH and E2 contents, polycystic ovaries do not have a higher proportion of atretic follicles than normal. Indeed, cells from anovPCO are hyperesponsive to FSH in vitro. This could be explained by stimulation of aromatase in vivo by either paracrine or, more probably, by endocrine factors, of which insulin is an arguable candidate.

Adult↗
PubMed1993

Insulin-like growth factor-I (IGF-I) inhibits production of IGF-binding protein-1 while stimulating estradiol secretion in granulosa cells from normal and polycystic human ovaries.

We have investigated the actions of FSH and insulin-like growth factor-I (IGF-I) on the production of IGF-binding protein-1 (IGFBP-1) by granulosa cells from unstimulated normal and polycystic (PCO) human ovaries and related these effects to those on estradiol (E2). IGFBP-1 concentrations were measured in granulosa cell-conditioned medium (48-h culture with 10(-7) M testosterone) and follicular fluid. IGF-I (50 ng/mL), in the absence of FSH, stimulated E2 production by granulosa cells from both normal and polycystic ovaries, and there was a synergistic action between IGF-I and FSH. Granulosa cells secreted IGFBP-1 in concentrations ranging from 20-500 pg/1000 cells.48 h, with cells from two of four normal and three of four polycystic ovaries showing a dose-related increase in IGFBP-1 production in response to FSH. In contrast, the addition of as little as 100 pg/mL IGF-I to cells incubated with testosterone or testosterone plus FSH, caused complete inhibition of IGFBP-1 production. FSH treatment produced the expected dose-related increase in E2 accumulation. IGFBP-1 was detectable in fluid from all sizes of follicle tested, but there was no correlation of IGFBP-1 concentrations with follicle size and no difference between normal and polycystic ovaries. These data indicate that IGFBP-1 and E2 are differentially regulated by IGF-1 in the human ovary.

Carrier Proteins↗
PubMed1991

Programming in vitro fertilization for a 5- or 3-day week.

OBJECTIVE: To schedule oocyte retrievals on either 5 or 3 days per week in in vitro fertilization (IVF) cycles. DESIGN: Human chorionic gonadotropin (hCG) administration was delayed by at least 24 hours in patients undergoing superovulation to avoid egg collections on weekends (group 1). Encouraged by the results, a further prospective study in which oocyte retrievals were programmed for only 3 days a week was undertaken (group 2). SETTING: Hammersmith Hospital, a tertiary referral unit. PATIENTS: All patients undergoing IVF treatment were included. MAIN OUTCOME MEASURES: To schedule oocyte retrievals on either 5 or 3 days per week. RESULTS: Only 4.0% of egg collections (12/303) occurred on weekends compared with 12.6% (22/175) before delaying hCG. In group 2 (n = 215), only four egg collections (2.1%) had to be performed out of schedule. Delaying administration of hCG had no detrimental effects. CONCLUSIONS: Delayed administration of hCG allows scheduling oocyte retrievals on either 5 or 3 days per week, leading to a substantial decrease in out-of-hours oocyte retrievals, reducing cycle costs, and facilitating efficiency. The method is applicable to assisted reproduction specialized units as well as district general hospitals that use gonadotropin-releasing hormone analogs in their superovulation regimens before IVF, gamete intrafallopian transfer, or intrauterine insemination.

Chorionic Gonadotropin↗
PubMed1991

Beneficial effects of a 24 h delay in human chorionic gonadotrophin administration during in-vitro fertilization treatment cycles.

We used a gonadotrophin-releasing hormone agonist (buserelin) and human menopausal gonadotrophin (HMG) for superovulation for in-vitro fertilization (IVF) in 143 patients. The patients were prospectively allocated to two balanced groups. In one group (47 patients) human chorionic gonadotrophin (HCG) was given when the three largest follicles were greater than or equal to 17 mm in diameter, with consistent levels of plasma oestradiol (standard group). In the second group (96 patients), HCG injection was delayed by 24 h (delayed group). In the delayed group of patients, proportionately more had clinical pregnancies (52.1% versus 34.0%). These results suggest that IVF patients will benefit from delayed administration of HCG. The traditional criteria for HCG administration should be changed when buserelin is used.

Adult↗
PubMed1990

Nine cases of heterotopic pregnancies in 4 years of in vitro fertilization.

The incidence of simultaneous intrauterine and extrauterine pregnancy increased after wider use of ovulation induction and the advent of techniques of assisted reproduction. Nine cases of heterotopic pregnancies are reported after in vitro fertilization (IVF) and embryo transfer (ET) between September 1984 and November 1988. The incidence of heterotopic pregnancies in clinical IVF pregnancies was 9 of 312 (2.9%). Superovulation and IVF-ET appear to predispose to heterotopic pregnancy, particularly after tubal disease.

Adult↗
PubMed1990

Inhibition of oestradiol production by epidermal growth factor in human granulosa cells of normal and polycystic ovaries.

Anovulation in women with polycystic ovary syndrome results from a disorder of FSH-mediated follicular maturation which may involve paracrine modulation of FSH action by intra-ovarian factors. Epidermal growth factor (EGF) is a potent inhibitor of FSH-stimulated oestradiol production in the rat and has also been shown to inhibit aromatase activity in human granulosa cells obtained after superovulation. The purpose of this study was to investigate the action of EGF on granulosa cell function in human ovaries which had not been previously exposed to treatment with exogenous gonadotrophins and to compare the responses in tissue obtained from normal and from polycystic ovaries. Granulosa cells were obtained from antral follicles less than 10 mm in diameter after dissection of unstimulated normal or polycystic ovaries (PCO). Cells were pooled, washed, plated and incubated for 48h in the presence of 10(-7) M testosterone and various doses of human FSH. FSH dose responses were obtained with or without the addition of purified EGF (50 pg/ml). Testosterone in the absence of FSH resulted in a fourfold (range 2-7.5) increase in oestradiol accumulation in the medium after incubation of granulosa cells from both normal and polycystic ovaries. This increase was reversed by addition of EGF. FSH treatment stimulated a dose-related increase in oestradiol regardless of the origin of the granulosa cells. The peak E2 response to FSH, obtained at a dose of 1-2.5 ng/ml was a 20-fold increase above testosterone alone (range 4-55) in cells from PCO compared to sixfold (2.5-13) in cells from normal ovaries.(ABSTRACT TRUNCATED AT 250 WORDS)

Cells, Cultured↗
PubMed1988

Mechanism and management of ovulatory failure in women with polycystic ovary syndrome.

Polycystic ovary syndrome is the most important cause of chronic anovulation. In women who fail to respond to clomiphene, low-dose FSH given in a step-wise fashion can induce normal follicular growth and ovulation. The failure of the action of endogenous FSH in these women may be related to reduced biological activity of circulating FSH, but may also involve inhibition of its action at follicular level by polypeptide growth factors such as EGF.

Androgens↗