Effects of high-dose and multiple-dose gonadotropin stimulation on mouse oocyte quality as assessed by preimplantation development following in vitro fertilization

The effects of increasing the level of ovarian stimulation on preimplantation embryonic development were assessed using a mouse in vitro fertilization system. When F₁ hybrid (C57BL/6 × CBA/Ca) mice received a single injection of 5 IU pregnant mare's serum gonadotropin (PMSG) followed 60 hr later by 5 IU human chorionic gonadotropin (hCG) approximately 50% of the resultant postovulatory oocytes developed to the blastocyst stage following in vitro fertilization. Increasing the single dose of PMSG to 10 or 15 IU resulted in significant reductions in the frequency of development to the blastocyst stage. When one or two additional doses of 5 IU PMSG were administered 24 and 48 hr after an initial injection of 5 IU, lower frequencies of oocytes with the potential for full preimplantation development were again observed. This reduction in gamete quality was significantly greater when the final dose of PMSG was administered only 12 hr prior to hCG. The results suggest that excessive gonadotropin stimulation may compromise the quality of the preimplantation embryos obtained following in vitro fertilization and that the timing of gonadotropin administration may also be critical.     

In vitro fertilization and embryo transfer of rabbit oocytes collected at different times after P-LH injection

No difficulties were encountered in the collection of preovulatory oocytes from the follicles of rabbits. A mean of 11.7 ova were recovered by follicle puncture. In vitro fertilization of the preovulatory oocytes was influenced by their stage of maturation. The highest fertilization rate (83%) was obtained using oocytes collected 9 h after injection of P-LH shortly before ovulation. Only after pretreatment with FSH-P was it possible to fertilize some preovulatory oocytes without administration of P-LH. In vitro fertilized preovulatory oocytes developed in culture. After 4-5 days 47-64% reached the blastocyst stage; the corresponding rate for in vivo fertilized oocytes was 48%. After transfer of in vitro fertilized preovulatory oocytes 19-28% implantations were achieved.     

Enhancement of the developmental potential of mouse oocytes matured in vitro by gonadotropins and ethylenediaminetetraacetic acid (EDTA)

We attempted to improve the developmental potential of mouse oocytes matured in vitro. First, the effect of gonadotropin supplementation of the oocyte maturation medium was tested. The addition of follicle-stimulating hormone (FSH) or luteinizing hormone (LH) alone significantly increased the rate of development of inseminated oocytes to two-cell embryos, resulting in a twofold increase in blastocyst development. There was no significant difference between FSH and LH supplementation. However, the beneficial effect of FSH or LH was abolished when both were added together. Next, we tested the effect of ethylenediaminetetraacetic acid (EDTA) supplementation of the embryo culture medium. The addition of 10 M EDTA significantly enhanced the development of embryos derived from oocytes matured in vitro, both to two-cell embryos and to blastocysts. These data suggest that the inadequate development of embryos from oocytes matured in vitro results from a defect similar to that inherent in outbred mouse embryos showing the two-cell block in vitro.     

An intact zona pellucida is not necessary for successful mouse embryo cryopreservation.

OBJECTIVE: To determine the developmental potential of mouse embryos that underwent cryopreservation after micromanipulation of the zona pellucida. DESIGN: Gaps were produced in the zona pellucida of mouse oocytes or two-cell embryos by zona drilling with acid Tyrode's solution. Zona-drilled oocytes were fertilized in vitro and cultured to the two-cell stage. Two-cell embryos were frozen, thawed, and cultured to the expanded blastocyst stage. RESULTS: There was no difference in the rate of embryo survival post-thaw (248/318, 77% versus 288/345, 83.4%), or in the rate of development to the expanded blastocyst stage (91/248, 36.7% versus 88/288, 30.6%), between embryos that were zona drilled as oocytes and unmanipulated controls. Similarly, there was no difference in the rate of cryosurvival (206/217, 94.9% versus 168/187, 89.8%) or development to the blastocyst stage (154/206, 74.7% versus 132/168, 78.6%) between embryos that were fertilized in vivo and zona drilled at the two-cell stage and embryos that were unmanipulated. CONCLUSIONS: These findings indicate that small gaps in the zona pellucida, such as those that result from micromanipulation, do not significantly alter the ability of embryos to withstand cryopreservation.     

Cryopreservation of ICR mouse oocytes: improved post-thawed preimplantation development after vitrification using Taxol, a cytoskeleton stabilizer

Objective: To establish an effective cryopreservation method.

Design: In vitro model study.

Setting: Infertility Medical Center, Pochon CHA University.

Animal(s): Four-week-old ICR mice superovulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin.

Intervention(s): Vitrified-thawed oocytes were fertilized and subsequently cultured in vitro.

Main Outcome Measure(s): Post-thawed development, chromosome/spindle normalities, and blastocyst quality.

Result(s): More cumulus-enclosed oocytes were fertilized and developed to the 8-cell stage after vitrification and thawing than denuded oocytes. However, cryopreserved oocytes of both types had lower spindle and chromosome normalities than fresh oocytes, which resulted in reduced developmental competence after thawing. The addition of 1 μM of Taxol™, a cytoskeleton stabilizer, to vitrification solution greatly promoted the blastocyst formation of vitrified-thawed oocytes, compared with no addition (24.0% vs. 58.6%). No difference in blastocyst quality, which was evaluated by blastomere and inner cell mass cell numbers and inner cell mass cell per trophoblast ratio, was found between fresh oocytes and oocytes vitrified with Taxol™.

Conclusion(s): A vitrification solution consisting of 5.5 M ethylene glycol, 1.0 M sucrose, 10% fetal bovine serum, and 1 μM Taxol™ greatly improved post-thawed development of vitrified oocytes.     

The live birth in a woman with resistant ovary syndrome after in vitro oocyte maturation and preimplantation genetic testing for aneuploidy

We report the pregnancy and live birth achieved after in vitro maturation (IVM) of oocytes and PGT-A in a 23-year-old patient suffering from ovarian gonadotropin resistance. A woman with resistant ovary syndrome (ROS) had secondary amenorrhea, high FSH levels (25.34 mIU/mL) and LH (29.6 mIU/mL), low estradiol levels (15.2 pg/mL), and high serum AMH levels (38.0 ng/mL), associated with an increased antral follicle count (AFC) of 45. Without gonadotropin priming and HCG trigger, ultrasound-guided transvaginal oocyte retrieval was performed. Aspiration of antral-stage follicles allowed the retrieval of 15 immature oocytes. After oocyte collection, immature oocytes were cultured in the IVM medium. Following IVM, six of them reached metaphase II stage. Resultant matured oocytes were fertilized by intracytoplasmic sperm injection (ICSI). Embryos obtained were cultured to the blastocyst stage. On day 5, three embryos reached blastocyst stage. Trophectoderm biopsy and PGT-A were performed on two better quality embryos on day 5 after fertilization. Two biopsied embryos were reported to be euploid. PGT-A was performed utilizing next-generation sequencing (NGS\MPS). One embryo was transferred in an artificial thaw cycle and resulted in a viable intrauterine pregnancy and live birth. Our experience indicates that there is no requirement for gonadotropin stimulation and use of b-hCG trigger prior to IVM in patients with ROS. The results suggest that oocytes obtained with IVM in patients with ROS are capable of meiotic and mitotic division, fertilization, and generation of euploid embryos. IVM appears to be a valuable approach in patients with ROS, allowing them to have genetically connected offspring.

     

Pregnancies caused by in vitro fertilization in cycles, stimulated with human hypophyseal gonadotropin and chorionic gonadotropin

In a program of in vitro fertilization, laparoscopies for oocyte aspiration were performed on 35 patients receiving human pituitary gonadotropin (hPG) and human chorionic gonadotropin (hCG). Of the 122 preovulatory oocytes which were recovered from these patients, 44 (36%) were fertilized and cleaved, and were transferred. 144 immature oocytes were collected, and attempts were made to mature these in vitro. 40 oocytes (28%) could be fertilized and cleaved, and were transferred. Eight pregnancies resulted from 32 embryo transfers (25%), and 22,9% from laparoscopies, respectively. Of the eight pregnancies, there were three preclinical abortions and two clinical abortions, and three patients are well along in the pregnancy. Among the three patients there is one twin pregnancy.     

Vital initiation of pregnancy (VIP) using human menopausal gonadotropin and human chorionic gonadotropin ovulation induction: phase II--1981

In a program for in vitro fertilization, laparoscopies for oocyte aspiration were performed on 24 patients receiving human menopausal gonadotropin and human chorionic gonadotropin. Of the 40 preovulatory oocytes that were recovered from these patients, 33 (83%) were fertilized and 30 (75%) cleaved and were transferred. Ten immature oocytes were collected, and attempts were made to mature these in vitro prior to insemination. All ten oocytes (100%) did fertilize, and seven (70%) cleaved and were transferred. Morphologic variation was noted between cleaving conceptuses, even in those conceptuses responsible for establishing pregnancies. Five pregnancies resulted from 19 embryo transfers (26%).     

Superovulation-induced transient hyperprolactinemia in human in vitro fertilization and embryo transfer

To examine the effects of transient hyperprolactinemia on in vitro fertilization and embryo transfer, 61 cycles in 50 euprolactinemic ovulatory women with irreparable tubal diseases were stimulated with clomiphene (CC) alone or CC and human menopausal gonadotropin followed by human chorionic gonadotropin (hCG). Serum prolactin (PRL) increased after hCG administration with peak values of 45.4 +/- 4.2 ng/ml on the day of laparoscopic oocyte aspiration. The highest serum estradiol (E2) concentration was found on the day before PRL peak and serum progesterone (P) began to increase after hCG injection concomitant with the PRL rise. The group having 50 ng/ml or more of PRL (34 cycles) had significantly higher levels of E2 during preovulatory and early luteal phase compared to those of the group having less than 50 ng/ml of PRL (27 cycles) but there was no significant difference between the P levels in the two groups. In the higher PRL group 72 (62.1%) of 116 collected oocytes were fertilized and 6 (20.0%) conceived. In the lower PRL group 45 oocytes (58.4%) of 77 were fertilized and 3 (12.5%) became pregnant. These data suggest that elevated serum PRL concentrations may have no effect on fertilization of oocytes in vitro or embryonic development.     

The effect of prolactin on murine in vitro fertilization and embryo development

Elevated levels of serum and follicular fluid prolactin occur in women undergoing ovulation induction with both clomiphene citrate and gonadotropin therapy. Prolactin's effect on oocyte fertilization and embryo cleavage has not been fully characterized. Using a murine model, we investigated the effect of prolactin on in vitro fertilization and subsequent embryo cleavage in media containing 150, 400, and 600 ng/ml purified mouse prolactin. No difference was found in fertilization rates when compared with control rates. Culture of both in vivo and in vitro fertilized two-cell embryos in murine prolactin at 150, 400, and 600 ng/ml showed no significant difference in blastocyst, morula, or embryo degeneration rates when compared with control rates. An assay for binding of murine prolactin to spermatozoa, oocytes, and the embryo at various cleavage stages revealed no specific murine prolactin binding. These in vitro experimental results fail to show a role for murine prolactin in effecting mature oocyte fertilization or subsequent embryo cleavage. The lack of binding of murine prolactin to the gametes and early developing embryo supports the in vitro findings.     

Cholesterol and steroid levels in human follicular fluids of human menopausal gonadotropin-induced cycles for in vitro fertilization

Fifty-eight follicular fluids (FF) were obtained from 18 women undergoing in vitro fertilization (IVF). Follicular development was induced by human menopausal gonadotropin (hMG) and follicular aspiration was performed 36 hr after an ovulatory dose of human chorionic gonadotropin (hCG). Two stages of oocyte-corona-cumulus complexes (OCCCs) morphological maturation was identified in this population: intermediate and mature. FF from which intermediate and mature OCCCs were obtained did not differ in 17-estradiol (E₂, progesterone (P), and cholesterol levels. Fifty OCCCs were fertilized and eight were not fertilized. No difference was found in E₂, P, and cholesterol levels in those two populations of OCCCs. Forty hours after insemination 50% of the oocytes were at the two-cell stage and 50% were at the three-cell stage. Steroids and cholesterol levels did not differ in FF from which those two groups of embryos originated. A direct correlation was found among the levels of cholesterol, E₂, and P in the FF. An inverted ratio of high-density lipoprotein (HDL) to low-density lipoprotein (LDL) and very low-density lipoprotein (VLDL) was found in FF compared to serum in 10 women. It is concluded that FF cholesterol levels have no value in predicting follicular maturation.     

Influence of human chorionic gonadotropin (hCG) and hCG internalization by granulosa cells on the rate of in vitro fertilization and embryonic development of human oocytes

Follicular fluids and granulosa cells were obtained from 28 aspirated follicles of nine women undergoing laparoscopy in an in vitro fertilization program. Follicular growth was stimulated by a human menopausal gonadotropin regimen and laparoscopy was performed 32 hours after human chorionic gonadotropin (hCG) administration. Follicular fluid 17 beta-estradiol (E2) levels were higher and hCG levels were lower in follicles with oocytes that fertilized and cleaved beyond two blastomeres (greater than two-cell group) than in those with nonfertilizable oocytes (NF group) (P less than 0.05). Compared to those from the NF group, granulosa cells from the greater than two-cell group secreted less progesterone (P) in vitro and had a fourfold increase in percentage of cells with internalized hCG. These results demonstrate that the steroidogenic capacity of granulosa cells from follicles whose oocytes fertilize and undergo accelerated embryonic development in vitro differs from the capacity of granulosa cells from NF follicles. This difference may be due to their enhanced ability to bind and subsequently internalize hCG.     

The ability of glass-bead column-filtered mouse spermatozoa to fertilize homologous eggs in vitro

Glass-bead columns have been used to separate mouse spermatozoa into motile and nonmotile fractions. The spermatozoa in the motile fraction are able to fertilize eggs in vitro. Significantly more of the two-cell embryos which develop from these zygotes reach the blastocyst stage than do two-cell embryos developing from eggs fertilized in vitro with unfiltered control spermatozoa.     

Ovarian stimulation for in vitro fertilization using pure follicle-stimulating hormone with and without gonadotropin-releasing hormone agonist in high-responder patients

There is a distinct pattern of response to gonadotropin stimulation in some patients marked by high peak estradiol (E₂) levels, multifollicular ovarians response, and elevated basal luteinizing hormone (LH)/follicle-stimulating hormone (FSH) ratios. We reviewed the stimulation profiles of five such high-responder patients who failed to conceive during in vitro fertilization with ovarian stimulation using pure FSH. All patients had baseline LH/FSH >1.5 and peak E₂>800 pg/ml. One cycle was canceled prior to hCG administration because of marked ovarian response (E₂>2500 pg/ml, multiple small follicles). In a subsequent cycle, all patients were pretreated with the gonadotropin releasing-hormone agonist (GnRHa) leuprolide acetete for 10–14 days prior to initiation of FSH for ovarian stimulation. Leuprolide was continued until the day of hCG administration. During cycles using GnRHa, there was a statistically significant decrease (P <0.05) in serum FSH on day 3 (<5 vs 8.3 mIU/ml), serum E₂ on day 3 (14.6 vs 34.6 pg/ml), and peak serum E₂ (1197.6 vs 1923.0 pg/ml). Patients during cycles with GnRHa had a greater number of preovulatory (8.6 vs 3.0) and total (12.4 vs 6.0) oocytes retrieved (P<0.05). The fertilization rate of preovulatory oocytes was also higher during cycles using GnRHa (83 vs 64%). Two pregnancies occurred in the cycles pretreated with GnRHa. These preliminary data indicate that in high-responder patients, a combination of GnRHa and pure FSH results in lower E₂ levels during the stimulation cycle and a greater number of total and mature oocytes retrieved and fertilized.     

In vitro maturation and fertilization of oocytes isolated from aged mice: A strategy to rescue valuable genetic resources

Purpose This project was to determine whether oocytes isolated from virgin aged mice, up to 18 months old, are competent to undergo cytoplasmic maturation in vitro and undergo fertilization and embryonic development. If so, oocyte maturation in vitro could be used as a strategy to rescue valuable genetic resources.Results Although the number of oocytes recovered from mice was greatly reduced with increasing age, the percentage of oocytes that underwent fertilization, cleavage, and development to the blastocyst stage was essentially unchanged up to 18 months of age. The success of cleavage to the two-cell stage was greater after maturation in vitro (81%) than gonadotropin-induced maturation in vivo (55%). About 20% (20/106) of the embryos derived from oocytes isolated from 18-month-old mice developed to term after embryo transfer.Conclusion Oocytes from virgin aged mice undergo normal cytoplasmic maturation in vitro. Higher percentages of oocytes from aged mice cleave to the two-cell stage after spontaneous maturation in vitro than after gonadotropin-induced maturation in vivo. Therefore, in vitro maturation and fertilization of oocytes could be used to rescue valuable genetic resources that might otherwise be lost because of age-related infertility.     

Effects of the supernatants of mixed lymphocyte cultures and decidual cell line cultures on mouse embryo development in vitro

The effects of supernatants of human mixed lymphocyte cultures (MLC), with or without human decidual cell line culture extract (decidual factor; DCF), on F₁-hybrid mouse embryo development in vitro from the two-cell stage were investigated. The development of mouse embryos from the two-cell stage through the expanded blastocyst stage was facilitated significantly by the addition of supernatants of not only MLC, but also MLC supplemented with DCF (MLCDCF) to the culture medium. Moreover, the supernatant of MLCDCF accelerated the attachment of the hatched blastocyst to the culture dish substratum and the outgrowth of trophoblasts in vitro. The findings indicate that the supernatant of MLCDCF facilitates the in vitro activity of mouse embryos for implantation and that the maternal immune response, along with the decidual tissue, contributes to the implantation processes.     

In vitro fertilization in Norfolk,Virginia, 1980–1983

Three years of progress of the Vital Initiation of Pregnancy (VIP) Program in Norfolk is reported. No conception resulted from 41 oocyte aspirations during spontaneous menstrual cycles in 1980. An average of 3.7 oocytes per cycle, or a 73.5% recovery rate, resulted in 362 human menopausal gonadotropin/human chorionic gonadotropin-induced cycles from January 1981 to March 1983. Forty pecent of the oocytes recovered from these cycles were preovulatory, 35% atretic, and 25% immature. Immature oocytes were often matured in vitro, fertilized, and found to produce pregnancies. A total of 62 pregnancies occurred, which represents a 17 or 23% pregnancy rate, based on laporoscopies or embryo transfers, respectively. There were 11 preclinical and 7 clinical miscarriages. Twenty-nine normal babies have been delivered, including a set of twins. The remainder appears to be normally progressing pregnancies. Polyspermia was observed in 8.8% of the fertilizable oocytes.     

Effects of luteinizing hormone and follicle stimulating hormone on the developmental competence of porcine preantral follicle oocytes grown in vitro

Background There has been controversy over the role of FSH in the regulation of preantral follicle development. LH is a survival and differentiation factor that increases oocyte maturation in FSH-supplemented cultures of mouse preantral follicles. However, little information exists on the action of LH and FSH in the developmental competence of porcine preantral follicle oocytes in vitro. Materials and methods Porcine preantral follicles were cultured for 3 days in the presence or absence of FSH or LH. Oocytes from these follicles were then matured, fertilized in vitro, and embryos were cultured. Estradiol secretion and histological analysis of cultured follicles were also carried out. Results FSH or combined LH and FSH significantly enhanced follicular growth compared to LH alone or the controls. Combined LH and FSH treatment of preantral follicles significantly increased the percentage (59 ± 5%) of oocytes competent to undergo cleavage to the two-cell stage after fertilization. A significant effect was seen on oocyte competence to develop from the two-cell to the blastocyst stage (30 ± 6%) compared to FSH alone treatment (45 ± 7 and 14 ± 5%, respectively). The amount of estradiol on days 2 and 3 of culture was significantly higher in follicles cultured with FSH (48.75 ± 17, 70.5 ± 14 pg/ml) or combined LH and FSH (63.25 ± 16, 72.5 ± 12 pg/ml) than that cultured with the untreated controls (16 ± 10, 5.66 ± 4 pg/ml). Conclusions The results indicated that FSH is essential for the in vitro growth of porcine preantral follicles, estradiol secretion, and for oocytes to acquire competence to resume meiosis and undergo fertilization and embryonic development. LH with FSH treatment of porcine preantral follicles can improve the quality of oocytes by promoting growth and a higher frequency of embryonic development.     

Meiosis-inducing substances in human preovulatory follicular fluid related to time of follicle aspiration and to the potential of the oocyte to fertilize and cleave in vitro

Meiosis-inducing substance (MIS) and steroid and gonadotropic hormones were investigated in 41 preovulatory follicular fluids (FFs) aspirated at either 0, 12, or 36 hours after human chorionic gonadotropin (hCG) administration in 25 women with clomiphene citrate-stimulated cycles. Twenty-one oocytes were recovered from these FFs and subjected to in vitro fertilization. MIS activity was present in 25 (61%) of the FFs. The frequency of MIS-active FFs increased from 11% (1 of 9) at 0 hours and 40% (2 of 5) at 12 hours to 81% (22 of 27) at 36 hours after hCG administration (P less than 0.001). The concentration of hormones in MIS-active FFs was not significantly different from that of MIS-inactive FFs. Twelve (86%) of 14 oocytes that fertilized and cleaved in vitro were recovered from MIS-active FFs. By contrast, all seven oocytes that remained unfertilized in vitro were recovered from MIS-inactive FFs. These findings support the notion that resumption of meiosis in the preovulatory oocyte is triggered by MIS in FF and suggest that follicular MIS production may be one of the factors that determines the success of in vitro fertilization and early embryonic development.     

Impact of ketorolac administration around ovarian stimulation on in vivo and in vitro fertilization and subsequent embryo development

Abstract

We performed this study to investigate the effect of ketorolac (a non-steroidal anti-inflammatory drug) administration around ovarian stimulation on in vivo and in vitro fertilization process. Sixty-four female mice (ICR) were injected with ketorolac (0, 7.5, 15 and 30?µg/d) for 3?d starting from the day of eCG treatment. In experiment 1, 41 mice were triggered by hCG and then mated; two-cell embryos were obtained and in vitro development up to blastocyst was observed. In experiment 2, 23 mice were triggered by hCG and mature oocytes were collected; in vitro fertilization rate and subsequent embryo development up to blastocyst was recorded. In experiment 1, the blastocyst-forming rates per in vivo fertilized two-cell embryo showed an inverse relationship with a dosage of ketorolac (97.6%, 64.2%, 35.4% and 25.9%). In experiment 2, degenerated oocytes were frequently observed in a dose-dependent manner (4.3%, 22.9%, 22.4% and 75.0%). Lower fertilization rates were noted in all the three ketorolac-treating groups; blastocyst-forming rate was significantly lower in 30-µg-treating group when compared with the control group. Administration of ketorolac around ovarian stimulation significantly affects the development of in vivo fertilized embryo in a dose-dependent manner. High-dose ketorolac could result in a poor oocyte quality and decreased embryo developmental competence.