Mouse embryos and quality control in human IVF.
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Animals↗
Biomedical subjects
G M Warnes
Publications and source records attributed to G M Warnes.
Decrease in luteal gonadotropin concentration in conception cycles after in vitro fertilization/gamete intrafallopian transfer.
The concentrations of the gonadotropins, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were measured in the luteal phase of the cycle in patients undergoing ovarian hyperstimulation. In nonconception cycles, FSH and LH were increased in the late luteal phase compared with conception cycles in which both gonadotropins were suppressed. Estradiol (E2) and progesterone concentrations increased in pregnancy cycles and may be the sole cause for the decreased gonadotropin concentrations as shown by equivalent concentrations of LH and FSH in both pregnancy and nonpregnancy cycles after matching for E2 concentrations. Subjects who subsequently had twin pregnancy or a spontaneous abortion were compared with those with a successful ongoing singleton conception. There were no significant differences relative to LH and FSH between the three groups, although in twin pregnancy FSH tended to be lower at day 16 from oocyte recovery. It is concluded that suppression of LH and FSH in hyperstimulated pregnancy cycles occurs after the time of the rising human chorionic gonadotropin concentrations in plasma.
Abortion, Spontaneous↗
Differential effects of gonadotrophin-releasing hormone agonists administered as desensitizing or flare protocols on hormonal function in the luteal phase of hyperstimulated cycles.
The incorporation of gonadotrophin-releasing hormone agonist (GnRHa) in in-vitro fertilization (IVF) stimulation protocols has led to doubt about the quality of the subsequent luteal phase. The effects of two GnRHa stimulation protocols on luteal phase concentrations of oestradiol (E2), progesterone (P), luteinizing hormone (LH) and follicle stimulating hormone (FSH) were compared with the standard clomiphene stimulation regimen. Subjects receiving clomiphene with human menopausal gonadotrophin (HMG, n = 377) showed essentially similar luteal phase P concentrations to those receiving leuprolide acetate/HMG as a desensitization protocol. Subjects receiving concomitant leuprolide and HMG from day 2 to utilize the flare effect of the GnRHa exhibited significantly lower P levels in the luteal phase compared to clomiphene/HMG and leuprolide desensitization protocols despite the addition of HCG support. This occurred despite equivalent E2 concentrations at the time of ovulation and identical numbers of oocytes recovered. LH concentrations in non-conception cycles were suppressed for at least 14 days in the luteal phase in both GnRHa protocols compared to clomiphene stimulation. Differences were less obvious in cycles where conception occurred suggesting that implantation may proceed more favourably when the luteal endocrinology was optimal. It is concluded that flare methods of GnRHa hyperstimulation are associated with significantly different luteal phases compared with clomiphene or desensitization protocols. It is proposed that the use of the flare type of stimulation may significantly influence the response of the granulosa cells to LH or HCG via gonadotrophin receptors or through altered post-receptor function.
Chorionic Gonadotropin↗
Experience with zona drilling and zona cutting to improve fertilization rates of human oocytes in vitro.
Zona drilling (ZD) and zona cutting (ZC) were used in an IVF programme to assist fertilization in semen defect patients. Twenty-seven patients consented to ZD where acidified Tyrode's was used to create a hole in the zona pellucida. In 19 patients, ZD increased the fertilization rate to 29% compared with 8% (P less than 0.001) in their routine IVF cycles, and in eight patients precluded from routine IVF, a fertilization rate of 14% was achieved. Twenty-two patients consented to ZC where a slit in the zona is made mechanically. In 12 patients ZC increased the fertilization rate to 31% compared with 14% (P less than 0.01) from previous routine IVF cycles, and in 10 patients precluded from routine IVF, a fertilization rate of 34% was achieved. In 13 cycles, 68 uncut control oocytes were inseminated. In five cycles both control and ZC oocytes were fertilized (n.s.d.). In eight cycles no control oocytes were fertilized compared with 27% of ZC oocytes. The polyspermy rate was 4.6%. Twenty-four per cent of ZD and 12% of ZC (P less than 0.01) oocytes and embryos were degenerate after 42 h. Both ZD and ZC can increase the fertilization rate of sub-optimal semen, however, in our hands neither technique produced a pregnancy.
Cell Survival↗
The leuprolide flare regime for in-vitro fertilization/gamete intra-fallopian transfer and embryo cryopreservation.
Gonadotrophin releasing hormone agonists (GnRHa) are now well established as adjuvant agents for in-vitro fertilization (IVF)/gamete intra-Fallopian transfer (GIFT) but several different modes of usage have been proposed. Our experience with 328 cycles of leuprolide used in a flare regime is reviewed. An endocrinologically proven flare effect was associated with a reduction of human menopausal gonadotrophin (HMG) usage (10 versus 16 ampoules) and a lower cycle cancellation/conversion rate (7.4 versus 11.3%). Overall, satisfactory rates of oocyte recovery (93%, mean number of oocytes 7.0), clinical pregnancy (24.4% per oocyte recovery) and pregnancy from frozen/thawed embryo transfers (14%) were achieved. The flare protocol appears to be a satisfactory choice for the majority of subjects but careful monitoring is required to avoid the potential for ovarian hyperstimulation.
Cryopreservation↗
A prospective trial of intrauterine insemination of motile spermatozoa versus timed intercourse.
STUDY OBJECTIVE: The efficacy of intrauterine insemination (IUI) of selected motile sperm. DESIGN: Prospective randomized sequential alternating cycle trial comparing IUI with luteinizing hormone (LH)-timed intercourse. SETTING: Clinical infertility service. PATIENTS: Couples selected included unexplained infertility (n = 73), cervical mucus hostility (n = 24), moderate semen defect (n = 110), and severe semen defect (n = 78). Two hundred eighty-five couples undertook 600 IUI cycles and 505 LH-timed intercourse. RESULTS: Overall, IUI was slightly more effective than LH-timed intercourse with a pregnancy rate of 6.2% versus 3.4% per cycle. When individual categories were considered only, IUI for severe semen defect was significantly better (5.6% versus 1.3%, P less than 0.05). The first IUI cycle was more effective when compared with both subsequent IUI cycles and the initial LH-timed cycle. Overall, 74% (27/37) of IUI pregnancies occurred in the first cycle. CONCLUSIONS: Compared with LH-timed intercourse, IUI provided little or no improved expectation of pregnancy but was beneficial in couples with severe semen defect. The occurrence of pregnancy was limited per cycle and confined essentially to the initial cycle of treatment. Continued IUI is considered to be unrewarding.
Cervix Mucus↗
Failure of body mass index or body weight to influence markedly the response to ovarian hyperstimulation in normal cycling women.
A retrospective analysis was performed of 368 normally cycling women treated with a single cycle of a standard ovarian hyperstimulation regime (CC 100 mg days 5 to 9 and hMG 150 IU days 6, 8, and 10) associated with either an IVF or GIFT program. Neither the peak serum E2 level attained nor the number of days of stimulation required bore a relationship to the BMI or the total body weight of these women. Whereas the mean number of oocytes aspirated from women with BMI less than 19.1 was higher (6.4 +/- 3.2) compared with obese women (BMI greater than 27.6, 4.8 +/- 2.6), the rate of fertilization was not different for both BMI extremes. It is concluded that factors other than BMI or total body weight have more important influences on the response to hyperstimulation in normal women.
Body Mass Index↗
Luteal function associated with single, multiple and ectopic embryo implantation in natural cycles or after ovarian hyperstimulation for in-vitro fertilization/gamete intra-fallopian transfer.
Levels of reproductive steroids and gonadotrophins were analysed retrospectively during the peri-implantation period following non-conceptional and conceptional natural cycles and in cycles associated with ovarian hyperstimulation for in-vitro fertilization or gamete intra-Fallopian transfer. In cycles not associated with conception, the luteal phase of hyperstimulated cycles (n = 100) was characterized by higher serum progesterone and oestradiol levels (P less than 0.01) and with an earlier decline in steroids than in natural cycles (n = 21). On day 11 (day of oocyte recovery = day 0), the level of progesterone in twin (n = 59) and triplet (n = 13) pregnancies was higher than singleton pregnancies (n = 176) (P less than 0.006, P less than 0.006 respectively) while those destined to abort (n = 66) had lower progesterone levels (P less than 0.01). Ectopic implantation (n = 11) had the lowest progesterone concentrations on day 11 (P less than 0.01) and this may imply a delay in corpus luteum rescue or a later implantation time than intrauterine conception.
Clomiphene↗
Adjuvant leuprolide in normal, abnormal, and poor responders to controlled ovarian hyperstimulation for in vitro fertilization/gamete intrafallopian transfer.
Fifty patients (normal responders) received either human menopausal gonadotropin (hMG) alone (control group) or leuprolide + hMG (leuprolide group). The use of leuprolide was associated with a reduction of hMG requirements (14.8 versus 17.8 ampules, P = 0.02) and the abolition of spontaneous luteinizing hormone surges (nil versus 3, P = 0.006). The rate of fertilization (87% versus 65%, P = 0.003) was higher in the leuprolide group. Pituitary and ovarian suppression was effected for 16 subjects who had previously shown a poor follicular response and a further 19 subjects who had previously responded abnormally. The poor responders required more hMG (43.9 versus 27.1 ampules, P less than 0.001), achieved a lower estradiol maximum (5.1 versus 12.1 nmol/l, P less than 0.001), and had fewer oocytes recovered (4.1 versus 11.5, P less than 0.001), than the abnormal responders.
Drug Therapy, Combination↗
Increase in digyny explains polyploidy after in-vitro fertilization of frozen-thawed mouse oocytes.
Fewer frozen-thawed mouse oocytes cleaved to the 2-cell stage compared to fresh control oocytes fertilized in vitro (46% vs 79%). The reduced rate of 2-cell formation was only partly explained by a decreased rate of fertilization (63% vs 85%). However, subsequent development to expanded blastocysts was not different (75% vs 78%). An increased frequency of second polar body retention by fertilized frozen-thawed oocytes compared with controls (11.8% vs 1.3%) was shown to be largely responsible for the higher incidence of polyploidy (16.3% vs 3.7%). The frequency of polyspermic fertilization was not different in the two groups (3.9% vs 2.3%).
Animals↗
Regulation of meiosis in mammalian oocytes.
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Animals↗
Prostaglandin F in the fallopian tube secretion of the ewe.
Oviducal secretions were obtained from conscious unrestrained ewes throughout the oestrous cycle via indwelling cannulae and the content of prostaglandin F (PGF) was determined by radioimmunoassay. Levels of PGF of up to 230 ng/ml were found in oviducal fluids obtained from ewes showing regular patterns of secretion and normal cyclical ovarian function as indicated by plasma progesterone measurement. Relatively large day to day fluctuations in content were evident, but there was no consistent relationship between concentration and stage of the oestrous cycle. Concentrations of PGF in excess of 100 ng/ml were common in preparations where autopsy later revealed infection or tissue irritation, and the concentration of PGF invariably exceeded 75 ng/ml when the concentration of protein in the oviducal fluid was abnormally high.
Animals↗
Changes in protein synthesis during maturation of sheep oocytes in vivo and in vitro.
The qualitative profiles of the proteins synthesized by sheep oocytes at various stages of maturation were determined by electrophoretic separation in one dimension on polyacrylamide SDS gels. No change in protein synthetic pattern was observed in ooce changes had taken place in at least 12 separate protein bands. Marked alterations in the synthesis of some proteins were apparent 15 h after LH; formation of proteins in 5 of the original bands was either reduced or not detectable, while new synthesis was evident from the appearance of 7 additional bands. The pattern of proteins produced by oocytes cultured within the follicle corresponded closely with that observed in vivo: changes in synthesis were initiated about 9 h after addition of gonadotrophin and were completed by 15 h. Oocytes cultured outside the follicle in a gonadotrophin-containing medium did not exhibit a change in protein synthesis and at 15 h only those proteins produced during the early stages of maturation were being synthesized.
Animals↗