Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Reproductive Technologies”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 523 records · Page 29Linked to original sources

Reproductive technologies 1998: options available for the cancer patient.

Recent advances in the field of reproduction have potentially opened opportunities for the preservation of the reproductive potential of young cancer patients with good long-term prognosis for survival. In the postpubertal male, cryopreservation of ejaculated sperm is both feasible and potentially successful. Semen parameters at the time of procurement are of minor significance; intracytoplasmic sperm injection (ICSI) can bypass sperm concentration and motility problems and can lead to successful fertilization. For the prepubertal male there are no clinically applicable options insofar as extraction and cryopreservation of postmeiotic sperm cells (mature spermatozoa or round spermatids) is not feasible. To date, efforts for culture of testicular tissue and in vitro maturation of male germ cells have not been successful. In both pre- and postpubertal females, cryopreservation of ovarian cortical tissue or enzymatically extracted follicles and the in vitro maturation of preantral follicles are of potential clinical use, but, to date, these approaches have been successful only in laboratory animals. An additional option available to the postpubertal female is the stimulation of ovaries with exogenous gonadotropins and retrieval of mature oocytes for cryopreservation. The recent application of ICSI in previously cryopreserved human mature oocytes has improved fertilization rates and has resulted in live births. Unfortunately, a shortcoming of this approach is the limited number of oocytes that can be harvested after stimulation of the ovaries. Further, all these approaches potentially harbor the risk of the cryopreservation of malignant cells with their subsequent reintroduction in the patient at a later date. This is a more realistic concern for patients suffering from hematologic or gonadal tumors. Finally, even though cryopreservation of embryos has been successfully used for many years, this option is not available to the pediatric and adolescent patient. It should not be forgotten that, even if the patients' own gametes are not available in the future, donor sperm and eggs provide the option for offspring and can give the opportunity to the females to carry a pregnancy as long as their uterus has not been affected by the cancer treatment. Given the rapid progress we are witnessing in the field of reproductive medicine, it is probable that in the very near future most of the options described and newer ones will be clinically available.

Adolescent↗

Human embryo implantation: current knowledge and clinical implications in assisted reproductive technology.

A pregnancy rate of approximately 15% per cycle renders the process of human reproduction inefficient. The cycle-dependent expression of molecules involved in the embryo-endometrial dialogue has lead to the identification of a 'window of implantation'. This is the unique temporal and spatial expression of factors that allows the embryo to implant (via signalling, appositioning, attachment and invasion) in a specific time frame of 48 h, 7-10 days after ovulation. Integrin molecules, L-selectin ligands, mucin-1, heparin-binding epidermal growth factor and pinopodes are involved in appositioning and attachment. The embryo produces cytokines and growth factors [interleukins, prostaglandins, vascular endothelial growth factor (VEGF)] and receptors for endometrial signals (leukaemia inhibitory factor receptor, colony stimulating factor receptor, insulin-like growth factors and heparin binding epidermal growth factor receptor). The immune system plays an important role. Immunomodulatory factors such as glycodelin, inhibin and interleukin prevent a graft-versus-host reaction. Angiogenesis controlled by VEGF and prostaglandins is needed for formation of a receptive endometrium and a placenta. Identification of these factors has led to their use as markers of implantation that may identify defects causing subfertility. An ideal marker of implantation is sensitive and specific, and easy to obtain without disturbing implantation. Glycodelin and leukaemia inhibitory factor (serum) and integrins and pinopodes (biopsies) are promising candidates.

Embryo Implantation↗

Development and application of ovine reproductive technologies: an Indian experience.

Sheep play an important role in the Indian economy by providing employment to a large population of marginal and landless farmers. The production from native breeds is relatively low due to their poor reproductive efficiency. Embryo transfer technology can be utilised for faster multiplication of elite animal to increase the genetic gain. A great deal of research is involved to overcome the constraints in the technology, i.e. expensive and complicated nature of the technology and low success rate. In order to avoid surgical involvement, procedures of laparoscope aided embryo collection and transfer have been developed. Although the use of FSH of ovine origin has given more consistent superovulatory response, but it is still too low to get sufficient numbers of progeny from a donor ewe. The progress made in cryopreservation of ram semen has opened the possibility for conservation and utilisation of frozen semen of elite rams in sheep improvement programme. The lambing rate obtained after laparoscope aided intrauterine artificial insemination with frozen semen is encouraging but the impetus is now to develop the non-invasive transcervical insemination technique.

Journal Article↗

Updating quality control assays in the assisted reproductive technologies laboratory with a cryopreserved hamster oocyte DNA cytogenotoxic assay.

PURPOSE: Despite advances in assisted reproduction, there is no progress in quality control bioassays. The objectives were to develop a comet assay to measure DNA fragmentation in thawed cryopreserved oocytes and compare this assay with one-cell mouse embryo bioassay. METHODS: Thawed hamster oocytes from a commercial source were incubated in culture media with either 0-, 50-, or 100-microM hydrogen peroxide, or, in media exposed to different contact materials and unknown proficiency analytes. Incubation time was 1.5 h at 37 degrees C. The oocytes were dried, fixed, stained with acridine orange, embedded in a mini-agarose layer and electrophoresis was carried out. Fluorescent images were analyzed. The results were compared with standard one-cell mouse assay data. RESULTS: The 100-microM hydrogen peroxide treatment caused greatest DNA fragmentation in the hamster oocytes at Hours 1 and 2. A dose response was observed. Intraassay coefficient of variation was 5.7%. Only one of the five materials tested passed both assays. The data for the unknown proficiency analytes were similar for both assays. CONCLUSIONS: The oocyte comet assay demonstrated DNA fragmentation in the presence of toxic substances. The detection of toxicity in two materials that passed the mouse bioassay suggested increased sensitivity in the new assay. The oocyte comet assay and the mouse bioassay results matched in the proficiency test. However, more studies are still needed to determine optimal sensitivity.

Animals↗

Assisted reproductive technology in Europe, 1999. Results generated from European registers by ESHRE.

European results of assisted reproductive techniques from treatments initiated during 1999, are presented in this third report. Data were collected mainly from pre-existing national registers. From 22 countries 538 clinics reported 258 460 cycles: IVF 125 370, ICSI 95 221, frozen embryo replacement (FER) 34 002 and oocyte donations (OD) 3867. In eight countries, where all clinics reported to the register, a total of 99 629 cycles was performed in a population of nearly 106 million, corresponding to 943 cycles per million inhabitants and 3.9 cycles per 1000 women aged 15-49 years. After IVF and ICSI the distribution of transfer of 1, 2, 3 and >or=4 or more embryos was 11.9, 39.2, 39.6 and 9.3% respectively. Huge differences existed between countries. For IVF the clinical pregnancy rate per aspiration and per transfer was 24.2 and 27.7% respectively. For ICSI the corresponding rates were 26.1 and 27.9%. These figures represent relative increases by 2.2 to 5.2% compared with 1998. The distribution of singleton, twin, triplet and quadruplet deliveries for IVF and ICSI combined was 73.7, 24.0, 2.2 and 0.1%. This gives a total multiple delivery rate of 26.3%. Triplet deliveries after IVF and ICSI ranged from 0.3-7.0% between countries. Compared with 1998, the number of reported cycles increased by 11% and the clinical pregnancy rate per transfer increased from 27.0 to 27.7% after IVF and from 26.8 to 27.9% after ICSI. Multiple deliveries after IVF and ICSI remained unchanged at 26.3% in 1999.

Adolescent↗

Assisted reproductive technology in Europe, 2000. Results generated from European registers by ESHRE.

European results of assisted reproductive techniques from treatments initiated during 2000 are presented in this fourth annual report. Data were collected mainly from pre-existing national registers. From 22 countries, 569 clinics reported 279 267 cycles: IVF 126 961, ICSI 99 976, frozen embryo replacement (FER) 45 800 and oocyte donations (OD) 6530. In nine countries where all clinics reported to the register, a total of 142 174 cycles were performed in a population of 166 million, corresponding to 856 cycles per million inhabitants. After IVF and ICSI, the distribution of transfer of one, two, three and >or=4 embryos was 12.1, 46.7, 33.3 and 6.8%, respectively. Huge differences existed between countries. For IVF, the clinical pregnancy rate per aspiration and per transfer was 24.7 and 28.4%, respectively. For ICSI, the corresponding rates were 26,6% and 28,7%. These figures represent increases of 0.7 and 0.8% compared with 1999. The distribution of singleton, twin, triplet and quadruplet deliveries for IVF and ICSI combined was 73.6, 24.4, 2.0 and 0.04%. This gives a total multiple delivery rate of 26.4%. The range of triplet deliveries after IVF and ICSI ranged from 0.3 to 7.0% between countries. Compared with 1999, the number of reported cycles was increased by 8% and the clinical pregnancy rate per transfer was increased by 0.7% after IVF and by 0.8% after ICSI. The total multiple delivery rates after IVF and ICSI remain unchanged during the last 4 years.

Adolescent↗

Assisted reproductive technology in Europe, 2001. Results generated from European registers by ESHRE.

European results of assisted reproductive techniques from treatments initiated during 2001 are presented in this fifth report. Data were collected mainly from already existing national registers. From 23 countries, 579 clinics reported 289 690 cycles with: IVF 120 946, ICSI 114 378, frozen embryo transfer (FER) 47 195 and egg donation (ED) 7171. Overall this represents a 4% increase since the year 2000. For the first time, results on European data on intra-uterine inseminations (IUIs) were reported from 15 countries. A total of 67 124 cycles [IUI husband'sperm (IUI-H) 52 949 and IUI donor sperm (IUI-D) 14 185] were included. In 12 countries where all clinics reported to the register, a total of 108 910 cycles were performed in a population of 131.4 million, corresponding to 829 cycles per million inhabitants. For IVF, the clinical pregnancy rate per aspiration and per transfer was 25.1 and 29.0%, respectively. For ICSI, the corresponding rates were 26.2 and 28.3%. These figures are similar to the results from 2000. After IUI-H, the clinical pregnancy rate was 12.8% in women <40 and 9.7% in women > or =40 years of age. After IVF and ICSI, the distribution of transfer of one, two, three and > or =4 embryos was 12.0, 51.7, 30.8 and 5.5%, respectively. Compared with the year 2000, fewer embryos were transferred, but huge differences existed between countries. The distribution of singleton, twin and triplet deliveries for IVF and ICSI combined was 74.5, 24.0 and 1.5%, respectively. This gives a total multiple delivery rate of 25.5%, compared with 26.9% in the year 2000. The range of triplet deliveries after IVF and ICSI differed from 0.0 to 8.2% between countries. After IUI-H in women <40 years of age, 10.2% were twin and 1.1% were triplet gestations.

Age Distribution↗

Assisted reproductive technology in Europe, 2002. Results generated from European registers by ESHRE.

European results of assisted reproductive techniques (ART) from treatments initiated during 2002 are presented in this sixth report. Data was mainly collected from already existing national registers. From 25 countries, 631 clinics reported 324,238 treatment cycles with: IVF 122,634, ICSI 135,048, frozen embryo replacement (FER) 57 162, egg donation (ED) 7677, preimplantation genetic diagnosis/screening (PGD/PGS) 1563 and in vitro maturation (IVM) 154. Overall this represents a 12% increase since year 2001. For the second time, results on European data on intrauterine inseminations were reported from 17 countries. A total of 93,284 cycles [IUI-husband/partner (H), 78 505 and IUI-donor (D), 14,779] were included. In 13 countries where all clinics reported to the register, a total of 177,429 cycles were performed in a population of 193.7 million, corresponding to 916 cycles per million inhabitants. For IVF the clinical pregnancy rate per aspiration and per transfer was 26.0 and 29.5%, respectively. For ICSI the corresponding rates were 27.2 and 29.4%. These figures are marginally better than in 2001. After IUI-H the clinical pregnancy rate was 11.6% in women below 40 and 7.8% in women>or=40 years of age. After IVF and ICSI the distribution of transfer of 1, 2, 3 and 4 or more embryos was 13.7, 54.8, 26.9 and 4.7%, respectively. Compared with year 2001, less embryos were transferred, but huge differences existed between countries. The distribution of singleton, twin and triplet deliveries for IVF and ICSI combined was 75.5, 23.2 and 1.3%, respectively. This gives a total multiple delivery rate of 24.5%, compared with 25.5% in year 2001. The range of triplet deliveries after IVF and ICSI varied from 0.0 to 5.2% between countries. After IUI-H in women below 40 years of age, 10.2% were twin and 1.3% triplet gestations.

Adult↗

Current status of in vitro fertilization and the new reproductive technologies.

The rapid pace of development and refinement of in vitro fertilization and ancillary assisted reproductive techniques warrants periodic review to keep the reader abreast of the growth in this clinical and scientific arena. Although not exhaustive, this review targets key areas of special interest and significance, including oocyte and embryo micromanipulation for assisted fertilization and genetic analysis, advances in the approach to ovarian stimulation, and examination of the scientific model afforded by ovum donation.

Female↗