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Biomedical subjects

W B Schoolcraft

Publications and source records attributed to W B Schoolcraft.

At least 19 recordsLinked to original sources
PubMed2001

Impact of intramural leiomyomata in patients with a normal endometrial cavity on in vitro fertilization-embryo transfer cycle outcome.

OBJECTIVE: Assess the impact of intramural uterine leiomyomata and a normal endometrial cavity on IVF-ET cycle outcome. DESIGN: Retrospective case-controlled analysis. SETTING: Tertiary-care-assisted reproductive technology program. PATIENT(S): Three hundred ninety-nine consecutive fresh IVF-ET cycles were performed in patients with a normal precycle diagnostic hysteroscopy; patients were divided into four groups. Group 1: positive leiomyomata, age <40 years (n = 51 cycles); group 2: negative leiomyomata, age <40 years (n = 57 cycles); group 3: positive leiomyomata, age > or =40 years (n = 22 cycles); group 4: negative leiomyomata, age > or =40 years (n = 59 cycles). A subgroup of all group 2 patients aged 35-39 (group 2A, n = 113 cycles) was also evaluated as an additional control. INTERVENTION(S): Controlled ovarian hyperstimulation, IVF-ET. MAIN OUTCOME MEASURE(S): Implantation (IR), live birth (LBR) rates. RESULT(S): There were no significant differences in LBR among age-matched controls: group 1 (49%) versus 2 (57.5%) or 2A (57%) and group 3 (40.9%) versus 4 (32.2%). IR was significantly lower in group 1 (21.4%) versus 2 (33.3%) or 2A (33.9%) but not in group 3 (17.5%) versus 4 (11.6%). Implantation did not correlate with either mean leiomyoma diameter or volume. CONCLUSION(S): [1] LBR was not affected by the presence of intramural leiomyoma in IVF-ET patients with hysteroscopically normal endometrial cavities. [2] A significant decrease in IR was only noted in patients <40 years old. [3] Given the relatively high LBR in all groups, prophylactic surgical intervention cannot be justified, but precycle hysteroscopy evaluation is recommended.

Adult↗
PubMed2001

Laparoscopic management of hydrosalpinges before in vitro fertilization-embryo transfer: salpingectomy versus proximal tubal occlusion.

OBJECTIVE: To compare ovarian response and IVF-ET cycle outcome in patients with hydrosalpinges managed by either laparoscopic salpingectomy or proximal tubal occlusion. DESIGN: Retrospective analysis. SETTING: Tertiary-care assisted reproductive technology program. PATIENT(S): One hundred four consecutive fresh IVF-ET cycles in 94 patients with tubal-factor infertility. INTERVENTION(S): Laparoscopic salpingectomy (group 1: 35 cycles) or bipolar proximal tubal occlusion (group 2: 17 cycles), controlled ovarian hyperstimulation, and IVF-ET. Control groups consisted of both tubal-factor patients without hydrosalpinges (group 3: 37 cycles) and those with prior bilateral tubal ligation for sterilization (group 4: 15 cycles). MAIN OUTCOME MEASURE(S): Uterine artery Doppler flow, controlled ovarian hyperstimulation response, and implantation and clinical pregnancy rates. RESULT(S): There were no differences in mean uterine artery pulsatility indices or ovarian response among any of the groups. A trend toward a higher cycle cancellation rate in group 1 did not approach statistical significance. Clinical pregnancy and implantation rates were not significantly different between group 1 (57.1%, 29.2 +/- 5.9%, respectively) and group 2 (46.7%, 19.4 +/- 6.1%, respectively) or compared with those of controls. CONCLUSION(S): [1] Management of hydrosalpinges by laparoscopic salpingectomy or bipolar proximal tubal occlusion yielded statistically similar responses to controlled ovarian hyperstimulation and IVF-ET cycle outcome. [2] The latter approach may be preferable in patients who present with dense pelvic adhesions and easy access only to the proximal fallopian tube.

Adult↗
PubMed2001

Embryo transfer: techniques and variables affecting success.

OBJECTIVE: To review the literature on the variables affecting embryo transfer success or failure and to define technical factors associated with optimal outcome. DESIGN: Literature review. RESULTS: Avoidance of blood, mucus, bacterial contamination, excessive uterine contractions, and trauma to the endometrium is associated with optimal pregnancy and implantation rates after transcervical embryo transfer. A trial transfer, ultrasonographic guidance, and use of "soft" catheters appear to facilitate successful embryo transfer. CONCLUSION: An understanding of the variables associated with embryo transfer success together with adherence to techniques shown to facilitate atraumatic embryo transfer will enhance the efficiency of IVF by maximizing embryo implantation.

Blastocyst↗
PubMed2001

Noninvasive assessment of human embryo nutrient consumption as a measure of developmental potential.

OBJECTIVE: To determine the relationship between blastocyst development and morphology and embryo metabolism. DESIGN: Noninvasive assessment of carbohydrate uptake and ammonium production by individual embryos. SETTING: Private assisted reproductive technology unit. PATIENT(S): Patients donated, with consent, cryopreserved pronucleate embryos and noncryopreserved blastocysts. INTERVENTION(S): Culture of 60 thawed pronucleate embryos in sequential media to the blastocyst stage with concomitant noninvasive analysis of embryo metabolism and analysis of 13 blastocysts from noncryopreserved embryos. MAIN OUTCOME MEASURE(S): Pyruvate and glucose consumption as well as blastocyst formation and quality. RESULT(S): Pyruvate and glucose uptakes on day 4 were significantly higher by embryos that went on to form blastocysts than by embryos that failed to develop to the blastocyst stage. Glucose uptakes were greatest in those blastocysts of highest grade, whereas pyruvate uptakes were similar irrespective of blastocyst grade, indicating that glucose is the more important nutrient for the human blastocyst. Among blastocysts of the same grade from the same patient, there was considerable spread of glucose consumption, indicating that glucose consumption may be of use in identifying blastocysts for transfer. Ammonium production by individual embryos was also measured, reflecting amino acid transamination and use by the human embryo. CONCLUSION(S): The ability to identify in culture the embryo with the highest developmental potential will facilitate the move to single-embryo transfers.

Blastocyst↗
PubMed2001

Blastocyst versus day 2 or 3 transfer.

The formulation of new sequential culture media, capable of supporting the development of viable human blastocysts, has reopened the discussion regarding the best day for embryo transfer following in vitro fertilization (IVF). Although several laboratories have reported overall increases in implantation rate and IVF efficiency following the transfer of blastocysts, others have failed to observe any benefit from extended culture. While culture conditions for the mammalian embryo undoubtedly have improved significantly over the past few years, relatively little attention has been paid to the quality of oocytes derived from ovarian hyperstimulation or the quality and receptivity of the endometrium following such hormonal regimes. It appears that differences in controlled ovarian hyperstimulation are among the major factors determining embryo quality and subsequent implantation. This therefore has confounded comparisons between different laboratories. In spite of this there are a growing number of reports demonstrating that the advantages of extended culture and blastocyst transfer, such as increased implantation rates, are not limited to specific groups of patients or specific etiologies. Rather, blastocyst transfer may be of benefit to the majority if not all patients attending for IVF.

Blastocyst↗
PubMed2000

Blastocyst score affects implantation and pregnancy outcome: towards a single blastocyst transfer.

OBJECTIVE: To determine the relationship between blastocyst score and pregnancy outcome. DESIGN: Retrospective review of blastocyst transfer in an IVF clinic. SETTING: Private assisted reproductive technology unit. PATIENT(S): 107 patients undergoing blastocyst culture and transfer of two embryos. INTERVENTION(S): Culture of all pronucleate embryos in sequential media to the blastocyst stage (day 5), followed by transfer of two blastocysts. MAIN OUTCOME MEASURE(S): Implantation rates, pregnancy rates, and twinning were analyzed. RESULT(S): When a patient received two top-scoring blastocysts (64% of patients), implantation and pregnancy rates were 70% and 87%, respectively. The twinning rate in this group was 61%. When only one top-quality blastocyst was available for transfer (21% of patients), the implantation and pregnancy rates were 50% and 70%. The twinning rate for this group was 50%. In contrast, when only low-scoring blastocysts were available for transfer (15% of patients), implantation and pregnancy rates were 28% and 44%, and the twinning rate was 29%. No monozygotic twins were observed in this group of patients. CONCLUSION(S): The ability to transfer one high-scoring blastocyst should lead to pregnancy rates greater than 60%, without the complication of twins.

Adult↗
PubMed2000

Blastocyst culture and transfer increases the efficiency of oocyte donation.

OBJECTIVE: To determine the impact of blastocyst transfer on an oocyte donation program. DESIGN: Retrospective review of embryo transfer in an IVF clinic. SETTING: Private assisted reproductive technology unit. PATIENT(S): Two hundred and twenty nine patients undergoing oocyte donation. INTERVENTION(S): Culture of pronucleate embryos to either day 3 or day 5 followed by embryo transfer. MAIN OUTCOME MEASURE(S): Implantation rates, pregnancy rates, and multiple gestations were analyzed. RESULT(S): Implantation rates and pregnancy rates were significantly increased by moving to extended embryo culture and transfer on day 5. After day 3 transfers, implantation and pregnancy rates were 47.1% and 75%, respectively. In contrast, on day 5 these rates were increased to 65.8% and 87.6%. Concomitantly, there were significantly fewer embryos transferred on day 5 (2.1) compared to day 3 (3.2). CONCLUSION(S): Blastocyst transfer is a highly effective treatment for patients who receive donor oocytes, allowing excellent pregnancy rates while significantly reducing the incidence of high-order multiple gestations.

Blastocyst↗
PubMed2000

Evaluating strategies for improving ovarian response of the poor responder undergoing assisted reproductive techniques.

OBJECTIVE: To assess the efficacy of various controlled ovarian hyperstimulation (COH) regimens in the prior poor-responder patient preparing for assisted reproductive techniques. DESIGN: English-language literature review. PATIENT(S): Candidates for assisted reproductive techniques who had been defined as having a prior suboptimal response to standard COH regimens. INTERVENTION(S): A variety of regimes are reviewed, including increased gonadotropin doses, change of gonadotropins, adjunctive growth hormone (GH), luteal phase (long) GnRH agonist (GnRH-a) initiation, early follicular phase (flare) GnRH-a initiation, low-dose luteal phase (ultrashort) GnRH-a initiation, progestin pretreatment, and microdose flare GnRH-a initiation. MAIN OUTCOME MEASURE(S): Maximal serum E(2) levels, follicular development, dose, and duration of gonadotropin therapy, cycle cancellation rates, oocytes retrieved, embryos transferred, and clinical and ongoing pregnancy rates. RESULT(S): A lack of uniformity in definition of the poor responder and of prospective randomized trials make data interpretation somewhat difficult. Of the varied strategies proposed, those that seem to be more uniformly beneficial are microdose GnRH-a flare and late luteal phase initiation of a short course of low-dose GnRH-a discontinued before COH. CONCLUSION(S): No single regimen will benefit all poor responders. General acceptance of uniform definitions and performance of large-scale prospective randomized trials are critical. Development of a reliable precycle screen will allow effective differentiation among normal responders, poor responders, and those who will not conceive with their own oocytes.

Clinical Protocols↗
PubMed2000

Experience with progesterone gel for luteal support in a highly successful IVF programme.

Efficacy of luteal support from single daily administration of Crinone((R)) 8% (progesterone gel) was tested in 43 women in an IVF programme with historical pregnancy rates >50%. Results were compared with those achieved in 46 women concurrently undergoing IVF and receiving 50 mg i.m. progesterone, and with historical data. Pregnancy rates (PR) were evaluated approximately 2 weeks after undergoing IVF by human chorionic gonadotrophin (HCG) measurement (total PR), by ultrasound 2-4 weeks later (clinical PR), and by counting births. Prior experience with other progesterone formulations was compared with that of Crinone 8%. Demographic and IVF characteristics were comparable for both concurrently treated groups. Total PR, clinical PR and live birth rates were similar for the Crinone and the concurrent i.m. progesterone groups: 31 (72.1%) versus 34 (73.9%); 26 (60.5%) versus 28 (60.9%), and 23 (53.5%) versus 23 (50%) respectively. Clinical PR and live birth rates were also similar to the last data reported to the Society for Assisted Reproduction Therapy. Overall acceptability of Crinone 8% was excellent. Among subjects with prior i.m. injection experience, most patients (69.2%) agreed that the gel was easier to use, less painful (76.9%) and less time-consuming (61.5%) than i.m. injections. In conclusion, Crinone 8% offers an appreciable improvement, as it provides an effective luteal support option that avoids painful i.m. injections.

Adult↗
PubMed2000

Culture and transfer of viable blastocysts: a feasible proposition for human IVF.

In spite of the numerous advances in the field of human assisted reproductive technologies (ART) over the past 20 years, a rate-limiting factor in the overall efficiency of the procedure (the implantation rate) has remained at 10-30%. The development of sequential media has led to the ability to culture routinely the human embryo to the viable blastocyst stage. Transfer of such blastocysts has resulted in a significant increase in implantation rates. Increases in implantation rates following blastocyst transfer have been reported for specific groups of patients culminating in the elimination of high order multiple gestations. Of greater significance, however, is that the introduction of blastocyst transfer to all patients entering infertility clinics is associated with an overall increase in implantation and pregnancy rates. Blastocysts derived from the use of sequential media are readily cryopreserved and produce high implantation rates after transfer. Using a model to account for both total embryo utilization per cycle (transferred plus cryopreserved) and implantation rate, it has been calculated that extended embryo culture and blastocyst transfer is approximately 20% more efficient than the transfer of cleavage stage embryos on day 3. Furthermore, as the score of the blastocysts obtained using sequential media is directly related to implantation and pregnancy rates, it is possible to determine which patients should be offered a single blastocyst transfer, thereby addressing the issue of twins conceived through ART.

Adult↗
PubMed1999

Blastocyst culture and transfer: analysis of results and parameters affecting outcome in two in vitro fertilization programs.

OBJECTIVE: To determine whether previously described advanced blastocyst development and high implantation rates are confirmed in an expanded multicenter trial. DESIGN: Retrospective review. SETTING: Two private assisted reproductive technology units. PATIENT(S): One hundred seventy-four patients who underwent blastocyst culture and transfer. INTERVENTION(S): Culture of all pronucleate embryos in sequential media to the blastocyst stage (day 5) followed by ET. MAIN OUTCOME MEASURE(S): The number and percentage of blastocysts developed, implantation rates, pregnancy rates, and parameters that affected outcome were analyzed. RESULT(S): Only 3 of 174 patients failed to achieve blastocyst-stage ET. The mean blastocyst development rate was 48%. The ongoing pregnancy rate was 66.3% per oocyte retrieval, with a mean (+/-SE) of 2.2 +/- 0.05 blastocysts transferred and an implantation rate of 48% per blastocyst transferred. CONCLUSION(S): Blastocyst culture and transfer is an effective means of treating patients who respond well to gonadotropins. High pregnancy rates can be accomplished with low numbers of embryos transferred. Patients who failed to achieve ET were rare.

Adult↗
PubMed1999

Vitrification of mouse and human blastocysts using a novel cryoloop container-less technique.

OBJECTIVE: To vitrify mouse and human blastocysts with use of the cryoloop procedure and to assess subsequent development. DESIGN: Controlled study of vitrification of mouse and human blastocysts. SETTING: Research department of a private assisted reproductive technology unit. PATIENT(S): Blastocysts that were not suitable to be frozen were donated from patients. INTERVENTION(S): Culture of pronucleate embryos in sequential media to the blastocyst stage. MAIN OUTCOME MEASURE(S): Survival of the vitrification procedure was assessed by reexpansion, hatching, and outgrowth in culture. In addition, the viability of mouse blastocysts was assessed after transfer to pseudopregnant recipients. RESULT(S): Vitrification of mouse blastocysts did not affect the ability to reexpand, hatch, or outgrow in culture. Furthermore, implantation rates and fetal development were equivalent for nonfrozen and vitrified blastocysts. Vitrified human blastocysts were able to hatch and outgrow in culture at rates similar to nonfrozen controls. CONCLUSION(S): Cryoloop vitrification was able to cryopreserve mouse and human blastocysts without any reduction in the ability to reexpand and hatch in culture. Furthermore, viability was not reduced by the cryoloop vitrification of mouse blastocysts.

Animals↗
PubMed1999

Antithyroid antibodies do not affect pregnancy outcome in women undergoing assisted reproduction.

The purpose of this study was to determine the association of antibodies to thyroglobulin and thyroid peroxidase and pregnancy outcome in women undergoing assisted reproductive techniques. The study included three centres and retrospectively evaluated patient sera for antithyroid antibodies, then related the results to pregnancy outcome. Enzyme-linked immunosorbant assays for thyroglobulin and thyroid peroxidase antibodies were performed using two different commercially available kits. Controls included 200 healthy women of reproductive age. Women (n = 873) who were undergoing assisted reproductive techniques for pelvic adhesions, endometriosis, ovarian dysfunction, or unexplained/other were included. All women utilized a standard regimen of gonadotrophin releasing hormone agonist down-regulation followed by ovulation induction. Embryos were cultured for 3 days, at which time embryo transfer occurred. Statistical analysis utilized the two-tailed Fisher's exact test. Antithyroid antibodies were positive in 143 of 873 (16.4%) women undergoing assisted reproductive techniques while 29 of 200 (14.5%) normal controls were positive (not significant). Deliveries were achieved in 396 of 730 (54.2%) of women who had no thyroid antibodies versus 78 of 143 (54.5%) of women who had thyroid antibodies (not significant). No difference in biochemical pregnancies (not significant) or clinical pregnancy losses (not significant) were detected. Antithyroid antibodies were found no more frequently in women undergoing assisted reproductive techniques than in normal controls. There were no differences in pregnancy outcome based on antithyroid antibody positivity in women undergoing assisted reproductive techniques. These data do not support the testing or treatment for antithyroid antibodies of women undergoing assisted reproductive techniques.

Autoantibodies↗
PubMed1999

Culture and transfer of human blastocysts.

The transfer of the human embryo at the blastocyst stage during an in-vitro fertilization procedure is a way of increasing implantation rates. This, in turn, means that significantly fewer embryos are required to be transferred in order to establish a successful pregnancy. The result of this is that high order multiple gestations are eliminated, while maintaining high pregnancy rates, in in-vitro fertilization.

Blastocyst↗
PubMed1998

Culture and transfer of human blastocysts increases implantation rates and reduces the need for multiple embryo transfers.

OBJECTIVE: To determine whether the transfer of blastocysts on day 5, developed in sequential culture media, resulted in an increase in implantation rate compared with embryos transferred on day 3. DESIGN: Comparative study of embryo culture regimes. SETTING: Private practice assisted reproductive technology center. PATIENT(S): Twenty-three patients undergoing routine IVF cycles. INTERVENTION(S): Culture of embryos to day 3 in either standard culture conditions or a serum-free chemically defined medium. One hundred one embryos were subsequently cultured from day 3 to day 5 in a second serum-free medium specifically designed to support development of the blastocyst. MAIN OUTCOME MEASURE(S): Embryo cell number and quality on day 3. Blastocyst development on day 5. Implantation rate (determined by fetal heart) and ongoing pregnancy rate (PR). RESULT(S): Implantation rates for embryos transferred at the blastocyst stage of development were twice that observed for embryos transferred on day 3, around the eight-cell stage. Significantly more embryos were required for transfer on day 3, compared with day 5, to establish similar PRs. CONCLUSION(S): Viable human blastocysts can be obtained in sequential culture media in the absence of coculture and serum. Transfer of blastocysts in IVF will facilitate high PRs while limiting the number of embryos transferred and therefore minimizes the risk of multiple gestation.

Adult↗
PubMed1998

Human embryo viability: what determines developmental potential, and can it be assessed?

The understanding of the embryo's nutrient requirements and physiology has led to the development of more physiological culture media, capable of supporting acceptable levels of human blastocyst development in vitro. The success of such media can be attributed to catering to the embryo's changing nutrient requirements, while minimizing culture-induced stress, thereby facilitating normal cell function. Most important, blastocysts derived from such sequential culture systems have a high viability. The ability to identify those blastocysts from within a given cohort which have the highest developmental potential will lead to further increases in implantation and pregnancy rate. Such an approach should ultimately lead to the routine transfer of a single blastocyst in a given IVF cycle, while being able to maintain a high pregnancy rate.

Blastocyst↗
PubMed1998

A prospective randomized trial of blastocyst culture and transfer in in-vitro fertilization.

The effectiveness of blastocyst culture and transfer in human in-vitro fertilization (IVF) was evaluated in a prospective randomized trial in patients having a moderate to good response to gonadotrophin stimulation. Embryos were transferred either on day 3 after culture to around the 8-cell stage in Ham's F-10 medium supplemented with fetal cord serum, or on day 5 after culture to the blastocyst stage in the sequential serum-free media G 1.2 and G 2.2. The pregnancy rates after transfer on day 3 or day 5 were equivalent, 66 and 71% respectively; however, significantly more embryos were transferred on day 3 (3.7) than on day 5 (2.2). The number of blastocysts transferred did not affect the implantation rate, and pregnancy rates when either two or three blastocysts were transferred were 68 and 87% respectively. The implantation rate of the blastocysts (50.5% fetal heart beat) was significantly higher compared to the cleavage stage embryos transferred on day 3 (30.1%). The percentage of blastocyst development was not affected by the number of 2-pronuclear embryos, or by maternal age. Irrespective of the number of blastocysts formed, pregnancy rates were similar. Furthermore, the pregnancy rate following blastocyst transfer in patients with 10 or more follicles at the time of human chorionic gonadotrophin administration was not affected by patient age. More than 60% of patients having blastocyst culture and transfer had supernumerary embryos for cryopreservation. The establishment of a pregnancy following thaw and transfer confirmed the viability of cryopreserved blastocysts cultured in the absence of serum or co-culture. The ability to transfer just two blastocysts while maintaining high pregnancy rates will therefore help to eliminate high order multiple gestations and improve the overall efficiency of human IVF.

Adult↗