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Results for “Embryo Transfer”

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PubMed1989

The influence of the interval between in vitro fertilization and embryo transfer and some other variables on treatment outcome.

This prospectively randomized study compares the outcome of 434 ETs 48 to 52 hours after insemination (day 2) and 324 ETs 72 to 76 hours after insemination (day 3). The influence of the interval between insemination and ET was assessed, as well as that of the number of embryos transferred, embryo quality, and the presence of supernumerary embryos. The mean number of embryos transferred after 2 and 3 days was equal (2.9 embryos/ET). The pregnancy rates per ET were not significantly different (21.9% versus 23.5%), but a higher percentage of viable pregnancies was observed after ET on day 3 (88.2% against 69.5% following ET on day 2). Treatment outcome was positively correlated with the number of embryos transferred and the presence of supernumerary embryos.

Abortion, Spontaneous↗

PubMed1991

Lack of placental protein 14 production in pregnancy after frozen embryo transfer, down-regulation of anterior pituitary and administration of exogenous oestradiol and progesterone.

The circulating levels of placental protein 14 (PP14) and progesterone were measured in three pregnancies resulting from the transfer of cryopreserved embryos. Two of these women had suppressed ovarian activity as a result of pituitary down-regulation with the luteinizing hormone-releasing hormone agonist (buserelin) prior to treatment with exogenous oestradiol and progesterone. After 14 days of oral oestradiol treatment and if the endometrial thickness was greater than 7 mm, progesterone was given intramuscularly for a further 14 days with embryo transfer on the third day of this treatment. On confirmation of pregnancy by human chorionic gonadotrophin analysis, progesterone administration was altered to transvaginal pessaries for maintenance of adequate progesterone levels and endometrial support. In the two women with ovarian suppression, PP14 levels remained below the 2.5th centile of the normal range for pregnancy. In the third pregnancy, embryo transfer was performed 3 days after a spontaneous luteinizing hormone surge in a normal menstrual cycle. In this pregnancy, PP14 levels were within the normal range. Ultrasonic examination confirmed three normal ongoing singleton pregnancies. These results suggest that the majority of PP14 production in normal pregnancy is under ovarian or anterior pituitary control and that the influence of progesterone is of a secondary nature.

Buserelin↗

PubMed2006

Transabdominal ultrasound-assisted embryo transfer and pregnancy outcome.

OBJECTIVE: To assess the clinical value of transabdominal ultrasound (TAS)--assisted embryo transfer on outcomes of in vitro fertilization--embryo transfer (IVF-ET) in comparison to the "clinical touch" method of transcervical embryo transfer by one physician and to determine if transabdominal ultrasound should be applied to all cases of embryo transfer in this practice. DESIGN: A retrospective comparison study. SETTING: A university-based IVF practice. PATIENT(S): Two hundred forty-nine patients who underwent transcervical transfer of fresh embryos created using autologous oocytes performed by the same physician from July 1, 2003, to June 30, 2004. INTERVENTION(S): On selected days, at time of embryo transfer, transabdominal ultrasound was performed to guide catheter placement depth approximately 1 cm from the uterine fundus. MAIN OUTCOME MEASURE(S): The presence of at least one gestational sac on ultrasound was compared in the two study groups; additionally, the clinical pregnancy rate (presence of fetal cardiac activity observed on ultrasound), the ectopic pregnancy rate, the biochemical pregnancy rate, and the implantation rate (number of gestational sacs identified on ultrasound per number of embryos transferred) between groups was evaluated. Characteristics of the two cohorts were analyzed to verify similarities between the treatment and control groups, including age of recipient, prior IVF history, day of transfer (day 3 or day 5 after retrieval), difficulty of transfer, the use of a tenaculum, and the quality and number of embryos transferred. RESULT(S): No statistical difference was seen in the presence or number of gestational sacs following embryo transfer with or without transabdominal ultrasound guidance. CONCLUSION(S): No additional advantage is conferred when using transabdominal ultrasound to perform embryo transfer. In experienced hands, the "clinical touch" method of embryo transfer yields equivalent results to transabdominal ultrasound-guided embryo placement. However, in patients with a prior history of difficult uterine sounding or embryo transfer, transabdominal ultrasound guidance may still play a role.

Abdomen↗

PubMed1995

Embryo score to predict implantation after in-vitro fertilization: based on 957 single embryo transfers.

The purpose of this study was to devise an embryo score to predict the likelihood of successful implantation after in-vitro fertilization (IVF). Unlike most studies dealing with the influence of embryo stage and morphology on pregnancy, our study was based on single rather than multiple embryo transfers. A total of 957 single embryo transfers were carried out. No delivery was obtained after any of the 99 transfers using 1-cell embryos or embryos obtained after delayed fertilization. In the remaining 858 transfers, the embryos had cleaved. Higher pregnancy rates were obtained with embryos displaying no irregular cells (11.7 versus 6.9%; P < 0.01) and embryos displaying no fragmentation (11.5 versus 8.1%; P < 0.05). The 4-cell embryos implanted 2-fold more often than embryos with more or less cells (15.6 versus 7.4%; P < 0.01). Based on these observations, we devised a 4-point embryo score in which embryos are assigned 1 point each if they (i) are cleaved, (ii) present no fragmentation, (iii) display no irregularities, and (iv) have four cells. Both pregnancy rate and take home baby rate were significantly correlated with embryo score. Each point of this score corresponds to a 4% increase in pregnancy rate. Interestingly, pregnancy rate was significantly lower in women aged > 38 years (8.2 versus 11.4%; P < 0.05), even though embryo quality was similar regardless of age. Single embryo transfer allowed us to define a simple and useful embryo score to choose the best embryo for transfer to optimize IVF and embryo transfer outcome. The use of this embryo score could decrease multiple pregnancies after multiple embryo transfers.

Adult↗

PubMed1992

Bioeconomic evaluation of embryo transfer in beef production systems: III. Embryo lines for producing bulls.

A model was developed for the economic evaluation of embryos for producing bull lines for use in commercial beef production. The fundamental concept underlying the model is that a cloned and sexed embryo of known genetic characteristics for beef traits is used to produce a bull. After reaching physiological maturity, the bull is used in natural matings. Equations relating feed energy requirements and growth rates based on NRC requirements and costs and returns discounted to present value allow investigation of expected economic merits of progeny from different embryo bull lines. The model has the flexibility to determine optimal embryo characteristics for different production environments. Model sensitivity to variation in progeny sex ratios, growth rates, yield and quality grades, and herd fertility characteristics was examined. Net present values (NPV) per embryo transferred were determined at the optimal marketing age of progeny produced from mating the bull to 30 cows per year for 5 yr. Relative to the lowest NPV of $18,209 for progeny with an expected quality grade of Select and yield grade of 4 at 400 d, increments in NPV ranged from $329 to $22,708 depending on differences in expected progeny carcass grade characteristics. The difference between NPV for 100% male and 40% male sex ratios was $7,518. The NPV differences between progeny growth rates of 1.6 and .9 kg/d holding herd conception rate constant at .9 and .5 were $8,311 and $4,611, respectively. The model evaluates relative economic values of embryo lines for producing bulls, accommodating interactions among progeny characteristics, and environments.

Animals↗

PubMed1986

Residual embryos in failed embryo transfer.

One hundred thirteen embryo transfers (ETs) were performed in an in vitro fertilization and ET program of which residual or extruded embryos were found in 17 transfers (15%). Residual or extruded embryos are those embryos found outside the uterine cavity, either at the cervical os, on the vaginal speculum, or remaining in the catheter after an ET. Patients were divided into two groups according to the method of inspection for residual embryos. In group I, microscopic visualization of the transfer catheter alone revealed that 9 of the 67 transfers (13.4%) had 17 residual embryos either at the catheter tip or adherent to mucus on the side of the catheter. In group II inspection of the catheter and cervical wash revealed that 8 of 46 ETs (17.4%) had 15 residual embryos that failed to be transferred during the initial attempt. Six of these 15 (40%) were found in the cervical wash medium. Thus, failure of the proper placement of embryos at the time of transfer may occur frequently. Evaluation of only the transfer catheter may result in a significant underestimation of the problem.

Animals↗

PubMed2005

Headaches in women undergoing in vitro fertilization and embryo-transfer treatment.

BACKGROUND: In vitro fertilization and embryo transfer has become a common therapeutic modality in modern fertility medicines. Treatment protocols are associated with exaggerated hormonal fluctuations in order to promote multiple follicular development and support of embryo survival. Estrogen is considered to be closely linked to migraine, and its extreme serum level fluctuations have been considered to trigger migrainous headaches. OBJECTIVE: To assess the prevalence, nature, and timing of headache attacks during the course of in vitro fertilization and embryo-transfer treatments. METHODS: We retrospectively evaluated the prevalence and the characteristics of headache among 98 women undergoing in vitro fertilization and embryo transfer therapy using a structured telephone interview. RESULTS: Out of the 98 evaluated patients 25 were migraine sufferers. Headache attacks during the in vitro fertilization and embryo transfer protocol were reported by 28.6% (n = 28) of the women and were significantly more prevalent among the migraineurs. The attacks were of debilitating severity in 82% (n = 23) of patients who reported headaches during treatment. Headache occurred most frequently following gonadotropin-releasing hormone (GnRH) analog induced hypothalamic-pituitary-ovarian axis downregulation, typically associated with very low 17-beta-estradiol (17-beta-E2) serum level. CONCLUSIONS: In vitro fertilization and embryo-transfer treatment might be associated with various degrees of headache. This is mostly observed in patients with migraine headache background and specifically during the downregulation stage of treatment, when very low levels of 17-beta-E2 are observed. (Headache 2005;45:215-219).

Embryo Transfer↗

PubMed1978

The value of embryo transfer to cattle breeding in Britain.

An analysis is made of the maximum expenditure which could be justified in embryo transfer in cattle is used to: increase the rate of genetic improvement of dairy or beef cattle; increase the frequency of twin-pregnancies; and expedite a change of breed. Estimates of maximum justifiable expenditure have been compared with an estimate of the cost of non-surgical transfer. Embryo transfer should be used in elite beef herds to increase selection intensity, particularly if bulls from such herds can be used for artificial insemination. Other commercial applications will not be economically justifiable until the cost of transfer has fallen by 50 to 80 per cent.

Animals↗

PubMed1983

Intra- and interspecific embryo transfer.

The procedures that are collectively referred to as embryo transfer (ET) have many uses. They were first used as research tools to study fetal-maternal physiology. Since the first successful mammalian embryo transfer in 1890, ET has been utilized for enhancement of genetic selection; diagnosis and treatment of infertility; control of infectious disease transmission; screening for genetic defects; propagation of rare and endangered species; and the study of developmental biology. Most of the embryo transfers have been intraspecific. A listing of the species includes rabbit, rat, sheep, mouse, goat, cattle, pig, hamster, ferret, mink, horse, baboon, cat, dog, water buffalo. In two species, rhesus monkey and humans, the successful embryo transfers have been limited to within-animal, homologous replacement of the embryos. There have been a few successful interspecific embryo transfers. The most common were between Bos taurus and B. indicus cattle. Other interspecific transfers involved Bos gaurus and B. taurus, cattle; Ovis musimon and O. aries, sheep; Equus asinus and E. caballus, horses. There are several examples of intergeneric embryo transfers in which embryos implanted but did not develop to term: sheep and goat, mouse and rat. The factors that determine the degree of compatibility between embryos and uteri of various species and genera are not clearly understood. The ability to hybridize successfully is probably a dependable indication of compatibility for embryo transfer. The limits of tolerance for differences between the donor and recipient in such factors as placental structure and gestation length have not been defined, but the recently developed technique of inner cell mass transfer will be very useful in such studies.

Animals↗

PubMed2005

Risk of transmission of Mycobacterium avium ssp. paratuberculosis by embryo transfer of in vivo and in vitro fertilized bovine embryos.

Over a 5-year interval, experiments were conducted to determine if Mycobacterium avium ssp. paratuberculosis (Map) is associated with in vivo and in vitro fertilized (IVF) embryos and whether it can be transmitted by embryo transfer. The present studies included: collection of embryos from five asymptomatic, naturally infected donors and transfer to uninfected recipients; collection of oocytes from two naturally infected donors with overt clinical signs; exposure of in vivo and IVF embryos to Map and transfer to uninfected recipients; and the inoculation (transfer) of "clean" IVF embryos to the uterine lumen of infected cows. The presence of Map was confirmed in the uterine horns of all asymptomatic, infected donors. None of the tested embryos, which were not used for embryo transfer, or unfertilized ova (two per batch), were positive for Map, as determined by culture (n = 19) or by PCR (n = 13). However, all in vivo fertilized embryos exposed to Map in vitro (and subsequently sequentially washed) tested positive for Map, by both culture (12 batches) and PCR (15 batches), whereas IVF embryos treated in the same manner tested positive on culture (51%, 18/35 batches) and by PCR (28%, 20/71 batches). Transferring both in vivo embryos and IVF embryos potentially contaminated with Map into 28 recipients resulted in 13 pregnancies and eight calves born without evidence of disease transmission to either the recipients or the offspring over the following 5-year period. In samples collected from one of the clinically infected animals, two of seven (28%) cumulus oocyte complexes (COC) and follicular fluid tested positive by PCR and 10/10 cumulus oocyte complexes on culture for Map. From the second clinically infected cow, three of five batches of IVF embryos (n = 20) were positive on PCR and two of four batches containing unfertilized oocytes and embryos were positive on culture. Only 10% of embryos reached the morula and blastocyst stage 10 days after fertilization. In conclusion, Map is unlikely to be transmitted by embryo transfer when the embryos have been washed as recommended by the International Embryo Transfer Society.

Animals↗

PubMed2004

A double embryo transfer on days 2 and 4 or 5 improves pregnancy outcome in patients with good embryos but repeated failures in IVF or ICSI.

The purpose of this paper was to evaluate the outcome of a double embryo transfer during the same cycle for patients who had had three or more implantation failures in IVF-ET or ICSI-ET programs after the transfer of good quality embryos in all attempts. Forty-five women who had had previous unsuccessful attempts in IVF-ET or ICSI-ET programs after transfer of good quality embryos (Group A) were included in the study. Group A was divided into two subgroups, Group A1 consisted of 34 patients who underwent embryo transfer on day 2 and day 4 after pick-up and Group A2 consisted of ten patients who underwent embryo transfer on day 2 and day 5 after pick-up. Forty-two other women with a similar unsuccessful history in IVF-ET (Group B) were studied as controls. The patients in this group had a day 4 or 5 only transfer without having an additional day 2 transfer. The outcome of the procedure was compared in the two groups. Double embryo transfer had beneficial effects on patients with good embryos but with previous failure attempts. These patients had a 38.2% clinical pregnancy rate and a 50% total pregnancy rate if the additional embryo transfer was done on day 4 and a 60% clinical and 60% total pregnancy rate if the additional embryo transfer was done on day 5. Our data showed that excellent pregnancy rates can be obtained with a commercially available medium and double embryo transfers on days 2 and 4 or 5 after pick-up for patients with good quality embryos that have had previous failure attempts in an IVF-ET program. Due to the fact that endometrial maturation varies considerably in each patient, an adequate endometrial maturation and improved uterine receptivity seem to be the reason for improved pregnancy rates with double embryo transfers. It was also shown that morullae have high viability and high potential for implantation and pregnancy.

Adult↗

PubMed2005

Comparison of the survival of human biopsied embryos after cryopreservation with four different methods using non-transferable embryos.

BACKGROUND: The standard embryo cryopreservation method is still less than optimal for biopsied embryos. The aim of this study was to compare the survival of biopsied embryos cryopreserved with four different methods using non-transferable embryos. METHODS: Abnormal embryos from one or three pronuclei and spare embryos of grade 3 and 4 were used for this study. Non-biopsied embryos were cryopreserved using the standard method as control. Biopsied embryos were cryopreserved using four methods as follows: standard method, modified freezing method, modified thawing method and vitrification. Blastomere survival and blastulation of frozen-thawed embryos were compared between the different methods. RESULTS: The proportion of embryos with > or = 50% blastomere survival and total blastomere survival rate of biopsied embryos were significantly higher with vitrification than the other three methods. Both the modified freezing and modified thawing methods had significantly higher embryo survival and total blastomere survival rates than standard methods. However, there was no significant difference in blastulation of surviving embryos in all the five groups. CONCLUSIONS: Non-transferable embryos derived from clinical IVF/ICSI are useful for evaluation of the optimal freezing procedures for biopsied embryos. Vitrification increases the survival rate of human biopsied embryos above standard and modified cryopreservation methods.

Biopsy↗

PubMed2001

Sex ratio and birth weights of infants born as a result of blastocyst transfers compared with early cleavage stage embryo transfers.

OBJECTIVE: To analyze the birth weights and sex ratio of infants born as a result of blastocyst transfer and compare them with data resulting from the transfer of early-cleavage stage embryos. DESIGN: Retrospective analysis. SETTING: Monash IVF (private in vitro fertilization clinic). PATIENTS(S): One hundred twenty-five infertile patients who became pregnant after IVF procedures involving blastocyst transfer. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Sex ratio and birth weights of infants born after blastocyst transfer. RESULT(S): The sex ratio of 129.6 for infants born after blastocyst transfer was not significantly different from the sex ratio calculated from data compiled by NPSU for births resulting from early cleavage stage embryo transfers at Monash IVF (100.6) and all other assisted conception units in Australia and New Zealand (97.9). No differences were observed in the combined mean birth weight of male and female infants born as a result of blastocyst transfers and early-cleavage stage embryo transfers. CONCLUSION(S): There is no evidence of abnormal fetal growth or a shift in the sex ratio for infants born as a result of blastocyst transfer when compared with the case of births resulting from early cleavage stage embryo transfers within our unit or all other assisted conception units in Australia and New Zealand.

Birth Weight↗

PubMed1992

Factors promoting embryo implantation in in vitro fertilization and embryo transfer.

The low implantation rate after embryo transfer (ET) is the most important problem to be solved in in vitro fertilization and embryo transfer (IVF-ET). Various factors which may affect embryo implantation in the endometrium have been examined. In this study, the influence of the timing of luteinization on the establishment of pregnancy was investigated. Follicle stimulation was performed by luteinizing hormone-releasing hormone agonist, human menopausal gonadotropin and human chorionic gonadotropin (hCG). hCG was injected on the day when the mean diameter of two follicles exceeded 16 mm, and 36 h after the injection the oocyte was retrieved. Progesterone (P4) supplement was started on the day of ovum retrieval (50 mg), followed by 30 mg for 14 days. The patients were divided into three groups: (1) the pregnant patients (n = 20: group Pre); (2) the nonpregnant patients without bleeding during P4 injection (n = 35; group N), and (3) the nonpregnant patients with bleeding during P4 injection (n = 30; group B). The number of follicles that developed, endometrial thickness, the day of operation, the number of oocytes harvested, the number of good quality oocytes, the number of oocytes fertilized, the number of embryos transferred, estradiol (E2) and P4 levels, and the E2/P4 ratio were examined. The endometrial thickness of group Pre (10.9 +/- 0.6 mm; mean +/- SEM) on the day of hCG injection was significantly (p less than 0.05) greater than that of groups N (9.0 +/- 0.4 mm) and B (9.2 +/- 0.3 mm).(ABSTRACT TRUNCATED AT 250 WORDS)

Buserelin↗

PubMed2006

Selection for faster development does not bias sex ratios resulting from blastocyst embryo transfer.

Concerns of possible male biased sex ratios with IVF exist due to reports of faster preimplantation development for male relative to female embryos in a variety of mammals, including humans. This study reports the first direct test of the hypothesis that selection for faster preimplantation development to the blastocyst stage increases the likelihood of a male birth. Gender outcomes of all live births resulting from blastocyst stage embryo transfer within a large assisted reproduction practice were reviewed, along with associated embryological records. The developmental stage of transferred embryos relative to the average developmental stage of all viable embryos in each cohort was related to gender outcomes by logistic regression analysis. Gender data were available for 1,184 children born from 815 pregnancies resulting from blastocyst stage embryo transfer during the study period. Data on preimplantation embryonic development were available for 737 cycles resulting in the birth of 1,075 children. There was no relationship between selection for developmental rate and the gender of resulting children. Numbers of male and female children were nearly identical within this patient population (593 male versus 591 female). These results indicate that offspring gender is unrelated to selection for developmental rate among blastocyst transfer cycles.

Blastocyst↗

PubMed2005

Embryo transfer in the dromedary camel (Camelus dromedarius) using asynchronous, meclofenamic acid-treated recipients.

A total of 40 (Day 7) embryos were recovered from the uteri of 10 superovulated camels. Recipient camels (n = 30) were prepared by injection with 20 (1/4)g of the gonadotrophin-releasing hormone analogue buserelin (i.v.) to induce ovulation and then treatment with 1 g meclofenamic acid (a prostaglandin synthetase inhibitor), orally, once on Day 7 and twice daily on Days 8 and 9 after ovulation and thereafter at a dose of 1 g day(-1) until 8 days after embryo transfer. Embryos were transferred into recipients on Day 8 (n = 10), Day 10 (n = 10) or Day 12 (n = 10) after ovulation and another 10 embryos were transferred into untreated recipients on Day 8 after ovulation as controls. In addition, serum samples from all recipient camels were recovered daily throughout the period of meclofenamic acid administration and for a further 7 days after treatment had ceased and were assayed for progesterone concentrations. Results showed that whereas only one of 10 of the control group of recipients (10%) was diagnosed pregnant, a total of eight of 10 Day 8 (80%), six of 10 Day 10 (60%) and seven of 10 Day 12 (70%) recipients were diagnosed pregnant by ultrasonography 12 days after the embryo had been transferred. Subsequently, however, four pregnancies were lost when the conceptus was aged between 22 and 60 days, but this is not considered above the early fetal mortality rate expected in camels after natural mating or after transferring camel embryos to untreated recipients. Serum progesterone concentrations remained elevated, above 2 ng mL(-1), throughout the period of meclofenamic acid administration in all recipient camels; thereafter, concentrations remained above 2 ng mL(-1) in pregnant animals, whereas in non-pregnant camels concentrations had declined to baseline values (<1 ng mL(-1)) within 3 days of the end of the treatment period. In conclusion, treatment of recipient camels with meclofenamic acid reduced the need for tightly timed synchrony between donor and recipient because pregnancies were established in recipients that had ovulated as much as 5 days ahead of the donor.

Animals↗

PubMed2003

The current status and future of commercial embryo transfer in cattle.

A commercially viable cattle embryo transfer (ET) industry was established in North America during the early 1970s, approximately 80 years after the first successful embryo transfer was reported in a mammal. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were recovered and transferred nonsurgically. Successful cryopreservation of embryos was widespread by the early 1980s, followed by the introduction of embryo splitting, in vitro procedures, direct transfer of frozen embryos and sexing of embryos. The wide spread adoption of ethylene glycol as a cryoprotectant has simplified the thaw-transfer procedures for frozen embryos. The number of embryos recovered annually has not grown appreciably over the last 10 years in North America and Europe; however, there has been significant growth of commercial ET in South America. Within North America, ET activity has been relatively constant in Holstein cattle, whereas there has been a large ET increase in the Angus breed and a concomitant ET decrease in some other beef breeds. Although a number of new technologies have been adopted within the ET industry in the last decade, the basic procedure of superovulation of donor cattle has undergone little improvement over the last 20 years. The export-import of frozen cattle embryos has become a well-established industry, governed by specific health regulations. The international movement of embryos is subject to sudden and dramatic disturbances, as exemplified by the 2001 outbreak of foot and mouth disease in Great Britain. It is probable that there will be an increased influence of animal rights issues on the ET industry in the future. Several companies in North America are currently commercially producing cloned cattle. The sexing of bovine semen with the use of flow cytometry is extremely accurate and moderate pregnancy rates in heifers have been achieved in field trials, but sexed semen currently is available in only a few countries and on an extremely limited basis. As of yet, all programs involving the production of transgenic cattle are experimental in nature.

Animal Rights↗

PubMed1990

[Cleaning of Sendai virus-infected mice by embryo transfer technique].

Mouse embryos (8-16 cells) were collected from Sendai virus (SV)-infected mice at 5 or 7 weeks after inoculation. All donors having embryo(s) were positive when tested by CF test or ELISA for SV antibody at the time of embryo collection. Most of the morphologically normal embryos developed (90.6%, 259/286) to morulae or blastocysts after culture for 26-28 hr. A total of 76 embryos cultured were transferred to the uteri of SV-free pseudopregnant recipients. Forty-seven young were obtained from these recipients (61.8% of development rate) and 46 young were successfully reared up to 10th week of age. All the recipients and the young were negative by testing SV antibody. These results indicate that the embryo transfer technique is useful for cleaning of SV-infected mice.

Animals↗