PubMed Health⌕ Search

Biomedical subjects

K J Go

Publications and source records attributed to K J Go.

13 recordsLinked to original sources

Ultrasound-guided soft catheter embryo transfers will improve pregnancy rates in in-vitro fertilization.

Attempts to improve clinical pregnancy rates after in-vitro fertilization (IVF) and embryo transfer are constantly being made. Two changes in technique of embryo transfer of potential clinical importance were evaluated over two contiguous time periods in order to observe any corresponding change in clinical pregnancy (CP) rate per transfer: (i) embryo transfer catheter; (ii) ultrasound guidance. Catheter choices were hard: Tefcat, Tom Cat, or Norfolk; or soft: Frydman or Wallace. Ultrasound visualization was considered to be excellent/good when the catheter could be followed from the cervix to the fundus by transabdominal ultrasound with retention of the embryo-containing fluid droplet; fair/poor if visualization could not document the sequence of events. Embryo transfers were performed in 518 cycles. CP rates per transfer using soft and hard catheters was 36 and 17% (P < 0.000) respectively. CP rates per transfer for transfers performed with and without ultrasound guidance were 38 and 25% (P < 0.002) respectively. A statistically significant difference was also noted when visualization ranks were compared. CP rates per transfer in all excellent/good ultrasound-guided transfers was 41.5 versus 16.7% for fair/poor transfers (P < 0.038). In conclusion, performance of embryo transfer with a soft catheter under ultrasound guidance with good visualization resulted in a significant increase in clinical pregnancy rates.

Adult↗

Live birth from a zygote cryopreserved for 8 years.

After a cryopreservation period of 8 years, four zygotes were thawed and transferred to the patient's uterine cavity. A singleton pregnancy resulted in the delivery of a normal male. This case report offers evidence that long terms of cryopreservation are consistent with full developmental potential post-thaw, and encourages further examination of imposing limits on length of storage of frozen concepti.

Adult↗

Is paracervical block anesthesia for oocyte retrieval effective?

OBJECTIVE: To quantitate pain relief associated with paracervical local anesthesia during transvaginal ultrasound-guided collection. DESIGN: The study was a prospective, randomized, double-blinded, placebo-controlled, and no treatment-controlled investigation. Pain scores for vaginal pain associated with entry into the cul-de-sac and global assessment for the entire procedure were generated separately by patient and physician. Variables evaluated include duration of procedure, patient weight and age, total number of vaginal and ovarian "follicular" punctures, number of oocytes retrieved, and amount of IV medication. SETTING: A private IVF-ET program. PATIENTS: Women in an IVF-ET program who volunteered to join the study (n = 101). INTERVENTIONS: Local anesthesia as a paracervical block compared with placebo or no injection during transvaginal oocyte retrieval, with all patients receiving IV sedation. RESULTS: Both vaginal and global pain scores, whether patient or physician assessed were lower for paracervical block than placebo. Agreements between physician and patient assessments of pain scores were close. Duration of the procedure was correlated with pain score. In general, a placebo effect on pain perception compared with no injection was not seen. CONCLUSION: Paracervical local anesthesia compared with placebo injection was associated with lower pain scores for both vaginal puncture and global assessment of the oocyte retrieval process but was not significantly better than no injection for global evaluation.

Adult↗

Bilateral and unilateral gamete intrafallopian transfer (GIFT) are not equivalent therapies if unilateral GIFT is chosen to avoid one abnormal tube.

PURPOSE: The relative effectiveness of bilateral and unilateral gamete intrafallopian transfer (GIFT) was compared. Bilateral GIFT, where possible, was the preferred method of transfer and occurred in 328 patients. One hundred sixty-seven patients undergoing unilateral GIFT were placed into one of seven categories based on the indication for unilateral GIFT. Three categories included patients with either historical or laparoscopic evidence of unilateral tubal abnormalities, two categories included patients without tubal disease, and two categories contained patients in whom the physician could not choose between unilateral or bilateral GIFT. RESULTS: Results demonstrate that unilateral GIFT in patients with either historical or laparoscopic evidence of unilateral tubal disease had significantly lower pregnancy and implantation rates than patients undergoing bilateral GIFT or those undergoing unilateral GIFT without evidence of tubal disease (P < 0.01). CONCLUSION: The presence of unilateral tubal abnormalities predicts a lower likelihood of pregnancy in patients undergoing unilateral GIFT through the tube presumed to be normal.

Adult↗

Predicting success of gamete intrafallopian transfer.

OBJECTIVES: To examine seminal parameters predictive for success in a cycle of GIFT and to construct an algorithm using pertinent seminal data as well as easily obtained historical data to predict pregnancy and viable pregnancy rates. DESIGN: A retrospective study of 544 cycles in 376 couples. SETTING: A private IVF-ET and GIFT center. PATIENTS: Couples in a GIFT program with a mean of 53.6 months of infertility who had failed to conceive with other therapies. INTERVENTIONS: Gamete intrafallopian transfer. MAIN OUTCOME MEASURES: Pregnancy as a function of laboratory historical data with emphasis on seminal parameters. RESULTS: Motility was the only seminal parameter that was predictive. Success was correlated with the number of oocytes returned and inversely related to female age. An algorithm to predict pregnancy in a GIFT cycle as well as viable pregnancy was constructed. CONCLUSIONS: Motility is the only seminal parameter predictive for success in a GIFT cycle. An easily programmable algorithm can be constructed to help patient and physician decide on the appropriateness of GIFT for each couple.

Adult↗

Recent advances in the treatment of male infertility.

The treatment of male infertility has been advanced by developments in the assays used to assess sperm function, methodologies for sperm preparation and augmentation of motility and potential fertilizing ability, and the various assisted reproductive techniques. These have made it possible for fertilization to be achieved even when apparently severe seminal deficits are encountered and have contributed to our knowledge regarding prefertilization and postfertilization events.

Adult↗

Correlations between the human sperm-hamster egg penetration assay and in vitro fertilization results.

The human sperm-hamster egg penetration assay (SPA) has been used to evaluate male fertility under in vivo conditions. The test is not only unstandardized, but agreement does not exist as to the lower limits of normal penetration rates. Therefore, it is not surprising that there is considerable doubt as to whether any correlation exists between SPA results and the behavior of sperm in an in vitro laboratory situation. We investigated this question by examining the SPA results and the subsequent fertilization and cleavage rates in the in vitro fertilization program at Pennsylvania Hospital. The sperm from men whose SPA results were 11% or more fertilized 86% of the morphologically normal and mature human oocytes to which they were exposed. Men whose SPA scores ranged from 1% through 10% fertilized 65% of human oocytes, and men whose sperm failed to penetrate hamster eggs still were able to fertilize 41% of the human oocytes. The differences between these groups are statistically significant. This information can be of practical prognostic value during in vitro fertilization cycles in which the number of mature oocytes seen ultrasonographically appears to be at a minimum.

Animals↗

Early experience with the GIFT procedure.

Gamete intrafallopian transfer (GIFT) was performed in 19 cycles on 15 couples whose infertility had proven resistant to other treatments. Indications included infertility associated with immunologic factors, seminal deficiencies, endometriosis and infertility without a diagnosed etiology. Any history or finding of tubal disease served as an exclusion. Infertility was primary in ten couples and secondary in five, three of whom had conceived previously with a semen donor. Stimulation protocols included clomiphene citrate (CC) and human menopausal gonadotropins, CC alone and gonadotropins alone. Males were screened with the hamster egg sperm penetration assay. Four conceptions were recorded, and three are ongoing. Advantages of this procedure include acceptance by the major orthodox religions, avoidance of extracorporeal incubation and physiologic entry of the embryo into the uterine cavity. Disadvantages include the inability to determine if fertilization has occurred in the absence of pregnancy, the theoretical risk of increased ectopic gestation and tubal infection, and perhaps an increase in multiple gestations.

Adult↗

Albumin-mediated changes in sperm sterol content during capacitation.

The role of albumin in mouse sperm capacitation was studied in relation to its activities as a lipid-solubilizing protein and a sterol acceptor. Two bovine serum albumins (BSA) which supported capacitation, Fraction V and fatty acid-free, both contained cholesterol and phospholipid but were without detectable levels of serum high-density lipoprotein (HDL). The lipid content of BSA could be reduced by trichloroacetic acid (TCA) precipitation; however, removal of all detectable lipids required precipitation with ethanolic acetone and diethyl ether extraction. In medium supplemented with Fraction V, fatty acid-free, or TCA-precipitated BSA, mouse sperm were capacitated as evidenced by their ability to fertilize eggs, concomitant with decreases in total cellular sterol and increases in phospholipid content. Delipidated BSA, fractionated on Sephadex G-100 in guanidine HCl also supported capacitation and mediated a 20% decrease in sperm sterol content, while cellular phospholipid levels remained unchanged. When BSA was modified by cholesterol augmentation, fertilization was inhibited in a cholesterol dose-dependent manner. These findings suggest that modulation of sperm lipid levels comprises an event of capacitation and that albumin mediates this process through its activity as a sterol acceptor.

Animals↗

Selective inhibition of acyl coenzyme A:cholesterol acyltransferase by compound 58-035.

Compound 58-035 (3-[decyldimethylsilyl]-N-[2-(4-methylphenyl)-1-phenylethyl]pro panamide) has been found to inhibit the accumulation of cholesteryl esters in both rat hepatoma (Fu5AH) cells and arterial smooth muscle cells in culture. To explore the specificity of 58-035, we have studied the esterification of cholesterol, retinol, and glycerides by the Fu5AH cell and by isolated membranes. Exposure of Fu5AH to cholesterol/phospholipid dispersions and 58-035 (greater than 100 ng/ml) for 24 h resulted in greater than 95% inhibition of cholesterol esterification while cellular free cholesterol increased slightly. Inhibition was also rapid; incorporation of [3H]oleate into cholesteryl [3H]oleate equaled only 12% of control value after 30 min with 58-035 at 5 micrograms/ml. In contrast, there was no decrease in [3H]oleate incorporation into phospholipids or diglycerides, nor was the esterification of [3H]retinol inhibited by 58-035. In microsomal fractions, acyl-CoA:cholesterol acyltransferase could be inhibited completely by 58-035, while activities of acyl-CoA: retinol acyltransferase and triglyceride synthesis proceeded at 75-100% of control values. These observations that 58-035 is highly selective allow the inference that acyl-CoA:cholesterol acyltransferase is a separate microsomal enzyme whose activity can be modulated independently from acyl-CoA:retinol acyltransferase and other cellular acyltransferases.

Acyltransferases↗