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PubMed2006

Relationship between endometrial thickness and embryo implantation, based on 1,294 cycles of in vitro fertilization with transfer of two blastocyst-stage embryos.

OBJECTIVE: To evaluate the relationship between endometrial thickness and clinical outcome of IVF and ET. DESIGN: Retrospective study. SETTING: Private assisted reproductive technology center. PATIENTS: One thousand two hundred and ninety-four infertility patients. INTERVENTIONS: IVF and fresh autologous ET of two blastocyst-stage embryos, including at least one good-quality blastocyst. MAIN OUTCOME MEASURES: Clinical pregnancy rate (PR) and spontaneous abortion rate. RESULTS: Endometrial thickness was greater in cycles resulting in pregnancy than in cycles not resulting in pregnancy (11.9 vs. 11.3 mm, respectively). Clinical pregnancy rates increased gradually from 53% among patients with a lining of <9 mm, to 77% among patients with a lining of > or =16 mm. Multiple logistic regression analysis indicated significant effects of age, embryo quality, and endometrial thickness on both clinical pregnancy rates and live-birth or ongoing pregnancy rates. There was also a marginally significant trend toward decreasing rates of spontaneous pregnancy loss with increasing endometrial thickness. CONCLUSIONS: Clinical pregnancy and live-birth or ongoing pregnancy rates increase significantly with increasing endometrial thickness, independent of the effects of patient age and embryo quality.

Abortion, Spontaneous↗
PubMed1999

Survival of cryopreservation and thawing with all blastomeres intact identifies multicell embryos with superior frozen embryo transfer outcome.

OBJECTIVE: To assess the impact of survival of cryopreservation and thawing with all blastomeres intact on the outcome of multicell frozen ET. DESIGN: Retrospective study. SETTING: Academic assisted reproductive technology program. PATIENT(S): One hundred sixteen exclusively multicell frozen ETs in 78 patients. INTERVENTION(S): Frozen ET. MAIN OUTCOME MEASURE(S): Relation of embryonic blastomere survival to the outcome of frozen ET (i.e., pregnancy). RESULT(S): When at least one embryo survived with all blastomeres intact, the total pregnancy rate (biochemical, clinical, or delivered) was 37.7%, the clinical pregnancy rate was 24.6%, and the delivered pregnancy rate was 18.8%. When no embryo survived with all blastomeres intact, the corresponding rates were 10.6%, 8.5%, and 6.4%. The differences in the total pregnancy rate and the clinical pregnancy rate were statistically significant. The delivered pregnancy rates approached statistical significance. CONCLUSION(S): Multicell embryonic survival of cryopreservation and thawing with all blastomeres intact identifies embryos with superior developmental potential.

Adult↗
PubMed2000

Where does the embryo implant after embryo transfer in humans?

OBJECTIVE: To investigate where human embryos implant after ET. DESIGN: Prospective analysis. SETTING: University hospital. PATIENT(S): Sixty infertile women without uterine fibroids, a major uterine anomaly, or a history of cesarean section. INTERVENTION(S): Transabdominal and transvaginal three-dimensional ultrasound examinations. MAIN OUTCOME MEASURE(S): The location of ET-associated air bubbles in the uterine cavity and the location of the resultant gestational sac. RESULT(S): Sixty ETs resulted in 22 pregnancies, and 32 gestational sacs were located. Twenty-six of the 32 embryos were within or between the area in which the catheter tip was situated and the area over which air bubbles had spread immediately after ET. CONCLUSION(S): In cases of pregnancy achieved through ET, approximately 80% of embryos implant in areas to which they initially are transferred and approximately 20% implant in other areas.

Adult↗
PubMed1988

Comparison of embryo recovery, embryo quality, oestradiol-17 beta and progesterone profiles in domestic cats (Felis catus) at natural or induced oestrus.

Domestic cats experiencing a natural or FSH-induced oestrus were studied. Mated cats produced fewer (P less than 0.01) unfertilized oocytes and more (P less than 0.01) morulato blastocyst-stage embryos of better quality after a natural oestrus than after FSH treatment. Serum oestradiol-17 beta concentrations were lower (P less than 0.05) and progesterone levels rose earlier (P less than 0.05) in the induced oestrus compared to the natural oestrus group. Morula/blastocyst-stage embryos from both groups transferred to 15FSH/hCG-treated recipients produced 3 pregnancies and 2 live-born litters (1 from a natural oestrus donor and 1 from an FSH-treated donor). These results indicate that fertilization rates and embryo quality in domestic cats appear to be compromised by the FSH treatment, probably because of altered oestradiol-17 beta and progesterone concentrations.

Animals↗
PubMed1997

Estrus, fertility, early embryo development, and autologous embryo transfer in laboratory woodchucks (Marmota monax).

Reproductive parameters were studied in female laboratory woodchucks over a 6-year period. The pregnancy rate in adult females after ad libitum exposure to a male (n = 643) was 72%; that after limited (4 to 8 h) exposure with video observations (n = 31) was only 37%. However, limited exposure resulted in a 75% ovulation rate, suggesting a problem with fertilization and not ovulation. The ovulation rate was 0% in the absence of mating (n = 10), suggesting that spontaneous ovulation is not the usual situation in this species. With ad libitum mating, fertility was greater (P < 0.05) for 2- to 4-year-old females (73%) than for 1-year-old (56%) or > or = 5-year-old (58%) females. Mean (+/-SEM) litter size at birth was greater (P < 0.05) for 2- to 5-year-old animals (4.0 +/- 0.1) than for 1-year-old animals (2.9 +/- 0.2). However, in 1-year-old females the neonatal mortality was low, and the litter size at weaning (2.4 +/- 0.3 pups) did not differ from that of older females (2.7 +/- 0.1 pups). The measurement of vulval diameter every 3 to 4 days in 31 adult females suggested that enlargement to > or = 7 mm was indicative of proestrus or estrus and was a good indicator of willingness to accept mounting by males. Vulval swelling > or = 7 mm (n = 31) lasted 5 to 47 days. Fertile mating occurred from 3 to 30 days after vulval diameter reached > or = 7 mm, near the time of peak enlargement (10.1 +/- 0.2 mm), and was followed in several days by a decrease in vulval size. Fifty-three females were allowed only limited (6 to 10 h) video-observed exposure to males, with (n = 26) or without (n = 27) another 12 to 24 h of unobserved exposure, and were examined surgically for ovulation and pregnancy at known times after mating. There were no consistent differences among nonovulating, ovulating nonfertile, and fertile females in the longest duration of mating (7.2 +/- 0.4 min) or in the number of matings lasting > or = 1 min (5.7 +/- 0.8). Compared with nonfertile females, fertile females experienced more matings > or = 3 min in duration (3.3 +/- 0.4 versus 1.8 +/- 0.2) and > or = 5 min in duration (2.9 +/- 0.4 versus 1.1 +/- 0.1). At postmating days 1, 2, 3, 4, 5, 6, and 7 the embryos were observed to be 1-, 4-, 4- to 32-cell morulae, 16- to 60-cell morulae, free-floating blastocysts, anti-measometrial peri-implantation blastocysts, and attached blastocysts respectively. Autologous transfer of day-5 uterine embryos of normal appearance into the noncontiguous contralateral uterine horn was performed in five females that had been subjected to a hemi-ovariectomy. Transfers resulted in pregnancy and litters in four of the five females. The results suggest that this large, circannual sciurid rodent can be successfully and predictably bred as a laboratory animal model, has vulval changes indicative of proestrus, is principally an induced ovulator, has an early embryo development rate similar to that of rats and mice, and may be amenable to reproductive technologies developed for more common laboratory rodents.

Animals↗
PubMed1994

Effects of glucocorticosteroids and insulin on tyrosine aminotransferase activity in isolated chick embryo hepatocytes and in intact embryos in ovo.

Hepatocytes were isolated from 17-day-old chick embryos. Steroid hormones or insulin, alone or when combined, did not alter tyrosine aminotransferase (TAT) activity in the isolated hepatocytes. However, TAT was stimulated by glucocorticoids in mixed hepatocyte and fibroblast cocultures; hormonal effects were not observed in pure hepatocyte cultures. Administration of hydrocortisone, dexamethasone, or triamcinolone (singly) to chick embryos in ovo resulted in an increase in hepatic TAT activity; insulin injection was without effect on the enzyme. The stimulation of TAT activity evoked by glucocorticosteroids in ovo was abolished by injection of cycloheximide or cordycepin. These observations contrast with reported glucocorticosteroid actions on TAT activity in fetal rat liver. It would appear that the differential regulatory effects on hepatic TAT by glucocorticosteroids are imposed by the distinct nutrient environments of chick embryos and fetal rats.

Animals↗
PubMed1990

In vitro survival of cells derived from isodiploid uniparental half embryos of the mouse after aggregation with normal embryos.

Fertilized mouse eggs, heterozygous for two allozymes of glucose phosphate isomerase (GPI) were bisected, and the resulting half eggs were diploidized with cytochalasin B. After separate aggregation with normal embryos carrying a third allozyme of GPI, the resulting chimaeras were kept in culture up to 10 days. The majority grew out on the culture dish during this period. By GPI analysis, 7.7% of the embryos were found to be chimaeric. Both types of uniparental cells, from gynogenetic and from androgenetic half eggs, were capable of surviving in chimaeras in vitro. These results are comparable with published data obtained by using uniparental embryos generated by micromanipulation.

Animals↗
PubMed1980

Study of some enzyme activities in cultured chick embryo brain nerve cells treated by chick embryo brain extracts.

Brain extracts from 8-day-old chick embryos have been shown to influence morphological development of dissociated brain cells from 7-day-old chick embryos in culture. Stimulatory effects on size of the neuronal somas and on growth of long processes were observed by adding the cytosol of the brain extract or the dialysate of the cytosol. These morphological changes parallel modifications of various enzyme activities according to the age of the cultures. Adenyl cyclase, (Na+,K+)- and Mg2+-ATPase, 5'-nucleotidase, choline acetyltransferase, and acetylcholinesterase activities were studied between 5 and 14 days of culture. Adenyl cyclase activity was strongly stimulated at 8 days by both extracts. (Na+,K+)- and Mg2+-ATPase activities were stimulated in 8-day-old cultures only by the dialysate. 5'-Nucleotidase activity was stimulated in 8-day-old cultures by the dialysate and in 11-day-old cultures by both extracts. Choline acetyltransferase activity was stimulated by the cytosol in 8-day-old cultures and by the dialysate in 11-day-old cultures. The total acetylcholinesterase activity was higher in 8-, 11-, and 14-day-old cultures treated with the cytosol. When the cells were treated with the dialysate, the activity was only higher in 14-day-old cultures. We also found that following the addition of brain extracts, the specific activity of the enzymes we studied was enhanced and became close to the values found in vivo during embryogenesis. Thus in parallel to the morphological modifications observed in nerve cell cultures treated by embryo brain extracts, biochemical variations especially involved in synaptogenesis and membrane development could be measured.

Acetylcholinesterase↗
PubMed1987

Serum prolactin response to embryo transfer during human in vitro fertilization and embryo transfer.

Serum prolactin (PRL) concentrations around the time of embryo transfer (ET) have not been studied, despite the fact that transient hyperprolactinemia regularly occurs in response to laparoscopy for oocyte recovery and ET itself may be stressful enough to induce a PRL rise. Hyperprolactinemia might compromise luteal support for implantation and contribute to the limited success of ET. We measured serum PRL concentrations in 10 normoprolactinemic women immediately before, during, and after ET and compared the PRL response around ET to that induced by laparoscopy as a measure of the competency of the stress-prolactin axis. Nine of ten patients demonstrated a significant PRL response to surgery. The mean (+/- SEM) intraoperative PRL concentration (124.0 +/- 19.6 ng/ml) was significantly higher than the preoperative level (12.3 +/- 2.4 ng/ml) (P less than 0.01). Three hours after surgery PRL levels had decreased (44.8 +/- 11.5 ng/ml) but remained above baseline. All subjects were normoprolactinemic 48 hr after laparoscopy. Serum PRL concentration did not change significantly in response to ET, with levels of 10.4 +/- 1.7, 12.4 +/- 1.1, and 10.6 +/- 1.8 ng/ml immediately before, during, and 3 hr after ET, respectively. While laparoscopy for in vitro fertilization--embryo transfer commonly induces hyperprolactinemia, the PRL rise is transient, with no carryover to the time of ET. Embryo transfer itself does not induce a significant PRL rise.

Embryo Transfer↗
PubMed1994

Relationship between the day of embryo transfer and the outcome in human in vitro fertilization and embryo transfer.

PURPOSE: To clarify the optimal date of embryo transfer (ET), we retrospectively analyzed the relationship between the day of ET and the outcome in human in vitro fertilization and embryo transfer (IVF-ET). METHOD: Of a total of 307 human IVF-ET cycles performed at Kyoto University Hospital between January 1990 and March 1994, we focused on 207 cases of IVF-ET cycles in which two or three good-quality embryos were transferred. These 207 IVF-ET cycles consisted of 54 Day 2 ET cycles, 79 Day 3 ET cycles, 46 Day 4 ET cycles, and 28 Day 5 ET cycles. We compared the pregnancy and live-birth (plus ongoing pregnancy) rates among these four ET groups. RESULTS: The pregnancy rates of ET on Days 2 to 4 were not significantly different, whereas Day 5 ET produced a significantly lower pregnancy rate (Day 2, 29.6%; Day 3, 32.9%; Day 4, 30.4%; Day 5, 10.7%). Similar results were obtained for the live-birth (plus ongoing pregnancy) rates (Day 2, 20.3%; Day 3, 18.9%; Day 4, 17.9%; Day 5, 7.1%). CONCLUSIONS: These results suggest that the day of ET does not fundamentally affect the pregnancy rate in human IVF-ET provided that transfer is made before Day 5.

Embryo Transfer↗
PubMed1984

Homotopic and heterotopic transplantations of quail tectal primordia in chick embryos: organization of the retinotectal projections in the chimeric embryos.

To study the adaptative capabilities of the retinotectal system in birds, the primordium of one optic tectum from 12-somite embryos of Japanese quail was transplanted either homotopically , to replace the ablated same primordium, or heterotopically, to replace the ablated dorsal diencephalon in White Leghorn chick embryos of the same stage. The quail nucleolar marker was used to recognize the transplants. The cytoarchitecture of the tecta and the retinal projections from the eye contralateral to the graft were studied on the 17th or 18th day of incubation in the chimeric embryos by autoradiographic or horseradish peroxidase tracing methods. Morphometric analysis was applied to evaluate the percentage of the tectal surface receiving optic projections. It was observed that: (i) quail mesencephalic alar plate can develop a fully laminated optic tectum even when transplanted heterotopically; (ii) retinal ganglion cells from the chick not only recognize the tectal neurons of the quail as their specific targets in homotopic grafts, but the optic fibers deviate to innervate the heterotopically grafted tectum; (iii) in the presence of a graft, the chick retina is unable to innervate a tectal surface of similar or larger size than that of the control tectum; (iv) tectal regions devoid of optic projections, whether formed by donor or by host cells, always present an atrophic lamination; (v) the diencephalic supernumerary optic tectum competes with and prevails over the host tectum as a target for optic fiber terminals.

Animals↗
PubMed1983

Action of testis graft from puromycin- or cAMP-pretreated donor embryos on the regression of Müllerian ducts in the female chick embryo.

Female chick embryos grafted with a piece of embryonic testis manifest in a high percentage of cases a regression of their Müllerian ducts (MD) under the influence of a anti-Müllerian hormone (AMH) secreted by the graft. Puromycine or cAMP administered to grafted females reduced significantly the percentage of those presenting a MD regression. In the present work puromycin or cAMP was administered to the male graft-donor embryos and not to the grafted females as was done previously. A testis graft from a puromycin-pretreated donor was significantly less active on the MD than that from a normal embryo. It could be then concluded that puromycin acted at the level of the testis by inhibiting the AMH production. On the other hand, the treatment of donors with cAMP did not modify their testes with regard to their action on the grafted female MD. This showed that cAMP directly protected the MD against the AMH.

Animals↗
PubMed2006

Day 3 compared with day 2 cryopreservation does not affect embryo survival but improves the outcome of frozen-thawed embryo transfers.

A retrospective study was performed to determine the differences in embryo survival and frozen-thawed embryo transfers outcome between cryopreservation performed on day 3 versus day 2. We conclude that freezing supernumerary embryos on day 3 provides similar thawing survival parameters, better implantation, pregnancy, and live-birth rates compared with day 2 cryopreservation.

Adult↗
PubMed2000

In vitro culture of bovine embryos in Ménézo's B2 medium with or without coculture and serum: the normalcy of pregnancies and calves resulting from transferred embryos.

The present study was designed to test the efficacy, as assessed by blastocyst production, of culturing slaughterhouse-derived bovine oocytes in Ménézo's B2 (B2) medium with or without serum and with or without buffalo rat cell (BRL) coculture. In addition, OPU-derived oocytes were cultured in B2-BRL coculture with or without serum for the first 72 h or TCM 199-BRL coculture with serum and the resulting embryos were transferred into recipients. Culture in B2 plus serum resulted in more blastocysts than B2 without serum, but both treatments produced far fewer blastocysts than did B2-BRL coculture. In addition, B2 with or without serum produced embryos of a lower stage of development, lower quality and fewer cells than did B2-BRL coculture. Serum restriction for the first 72 h of B2-BRL coculture did not result in a detectable difference in blastocyst production during 7 or 8 days of culture relative to coculture with no serum restriction. Embryos produced in B2-BRL coculture with serum restriction resulted in pregnancy rates, percentage of male fetuses, abortions, and congenital problems similar to those from B2 or TCM 199-BRL coculture with no serum restriction.

Animals↗
PubMed1982

Labelling of prolyl hydroxylase tetrameric subunits in freshly isolated chick-embryo tendon cells and in certain chick-embryo tissues in vivo.

The labelling of the subunits of prolyl 4-hydroxylase tetramers was studied in freshly isolated chick-embryo tendon cells and in chick-embryo tissues. In the former both the alpha- and beta-subunits of the tetramer were labelled during a 4 h labelling and 2 h chase period, although the radioactivity in the beta-subunit was much lower than in the alpha-subunit. The corresponding subunits of the enzyme from 12-day chick-embryo cartilaginous bone and heart were labelled in 7 h, again the beta-subunit much less than the alpha-subunit, the ratio of radioactivity in the beta-subunit to that in the alpha-subunit (beta/alpha-radioactivity) being 0.20 and 0.32 respectively. The beta/alpha-radioactivity then increased almost linearily with time between 7 and 24 h, by 9.5-fold in the cartilaginous bone and 3-fold in the heart, and beta/alpha-radioactivity values above 1.0 were reached. The free beta-subunit-size protein (the beta'-protein), which is also present in cells, had been labelled quite heavily by 7 h. The beta/alpha-radioactivity at 7h, determined in four tissues with different ratios of prolyl hydroxylase tetramers to total immunoreactive protein (tetramer percentage), was low in tissues with a high tetramer percentage. It is thus proposed that only a minor fraction of the beta'-protein must be processed to the tetrameric beta-subunit and utilized in the synthesis of the prolyl 4-hydroxylase tetramers.

Animals↗
PubMed2004

Two cycles with single embryo transfer versus one cycle with double embryo transfer: a randomized controlled trial.

BACKGROUND: With the aim of reducing the number of multiple pregnancies after IVF we investigated the effectiveness of two cycles with single embryo transfer (SET) and one cycle with double embryo transfer (DET) after IVF and calculated the cost-effectiveness of both strategies. METHODS: A randomized controlled trial was performed in 107 women, aged <35 years, in their first IVF cycle, with at least one good quality embryo. They were randomized to the SET (n = 54) or DET (n = 53) group using a computer-generated random block number table, stratified for primary or secondary infertility. RESULTS: The cumulative live birth rates per woman randomized of two consecutive cycles of SET [41%; 95% confidence interval (CI) 27-54] versus one cycle of DET (36%; 95% CI 23-49) were comparable, whereas the multiple pregnancy rate was significantly higher: 37% (95% CI 15-59) in the DET and 0% in the in the SET group (P = 0.002). Combining the medical costs of the IVF treatments (where 1.5 more SET cycles were required to achieve each live birth) and of pregnancies up to 6 weeks after delivery, the total medical costs of DET per live birth were 13,680 and 13,438 for SET. CONCLUSIONS: Two cycles with SET were equally effective as one cycle with DET, and the medical costs per live birth up to 6 weeks after delivery were the same. However, if lifetime costs for severe handicaps are included, more than 7000 per live birth will be saved after implementing SET. Because of the high probability of multiple pregnancies in this group of IVF patients, only SET should be performed.

Adult↗
PubMed1984

Influence of Concanavalin A on 3-O-methylglucose uptake in cultured chick embryo fibroblasts. Evidence for differences related to the age of embryos.

Concanavalin A (Con A) was found to inhibit hexose uptake in cultured fibroblasts derived from 8-day chick embryos and to stimulate this process in those derived from 16-day embryos. Con-A effects depended on the duration of contact with cells and lectin and were inhibited by alpha-methylmannopyrannoside. Con A was shown to mask about 70% of the hexose carriers in both 8- and 16-day embryo fibroblasts. Lectin altered the hexose uptake very rapidly. Con A only modified the Vmax of the uptake system and did not alter the Km. This indicates that either the number or mobility of hexose carriers were modified by Con-A treatment. The differential effect of lectin could be due to a modification of the hexose-carrier mobility during the embryonic differentiation of fibroblasts. Secondary effects may affect cell growth.

3-O-Methylglucose↗
PubMed1976

Collagen glucosyltransferase. Partial purification and characterization of the enzyme from whole chick embryos and chick-embryo cartilage.

A purification of over 2000-fold is reported for collagen glucosyltransferase from Triton X-100 extract of whole chick embryos and one of about 160-fold from similar extract of chick embryo cartilage. The addition of the detergent more than doubled the enzyme activity in the homogenates. The purified enzyme preparations from whole chick embryos showed one major band and two or three minor bands in polyacrylamide gel electrophoresis and were entirely free of collagen galactosyltransferase activity. The molecular weight of collagen glucosyltransferase from both sources was about 52000 -- 54000, as determined by gel filtration. In some enzyme preparations an additional form was observed, with an elution position corresponding to a molecular weight of about 130000. Manganese was the most effective metal co-factor for the purified enzyme, but partial replacement could be obtained with Co2+, Mg2+ and Ca2+, whereas no replacement was found with other metals. The activity of the purified enzyme was stimulated by the addition of dithiothreitol to the incubation system and inhibited by preincubation with p-mercuribenzoate. UDP-glucose or the collagen substrate partially protected the enzyme against p-mercuribenzoate inactivation in the presence of Mn2+ but not in its absence. Some protection was also noted with Mn2+ alone.

Animals↗