Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Reproductive Techniques”

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 163 records · Page 9Linked to original sources
PubMed2005

[Measurement of endometrial volume and endometrial thickness for assessment of endometrial receptivity in assisted reproductive techniques].

The authors investigated the role of 3D endometrial volume measurements as a predictor of clinical pregnancy in ART and comparison between endometrial volume and endometrial thickness in order to find the better predictor for endometrial receptivity in ART. Endometrial volume emerged recently as a new efficient predictor of endometrial response to hormonal stimulation and successful implantation. In this clinical study, participated 58 infertile patients undergoing IVF-treatment, during the period from 01.01.2004 till 01.01.2005. Endometrial volume of < 2 ml on the day of Embryotransfer (ET) was a better predictor for low endometrial receptivity, than Endometrial thickness on the same day and resulted in significant lower IVF clinical pregnancy and implantation rates. Endometrial volume > 2 ml on the day of ET was a positive predictor for ART outcome.

Embryo Implantation↗
PubMedDate not supplied

[Oocyte maturation. From animal experiments to human reproduction techniques].

The control of the oocyte growth and maturation are complex processus implicating endocrines (gonadotropines) and paracrine factors (growth factors, cytokines, steroids...), the paracrine regulation being under the endocrine control. The control of the cytoplasmic and nuclear maturation is realized by substances going through gap junctions from the follicular cells to the oocyte. Two of these substances, which are present in the follicular fluid, are responsible for maintaining the meiotic arrest: cyclic AMP and purines. Hormones or growth factors, which are able to affect the oocyte maturation both in vivo and in vitro, when they interact with their receptors stimulate enzymes which in turn stimulate the release of second messengers. Actually, the whole process that is oocyte maturation followed by fertilization in vitro does not give good results. This difficulty does not permit yet the freezing of immature oocytes which could be a solution in some cases encountered in Medically Assisted Procreation.

Animals↗
PubMed1997

Follicle aspiration, sperm injection, and assisted rupture (FASIAR): a simple new assisted reproductive technique.

OBJECTIVE: To describe the first successful application of a new fertility-enhancing technique. DESIGN: Case report. SETTING: Academic fertility program. PATIENT(S): A 36-year-old nulligravid woman undergoing inseminations with frozen-thawed donor sperm. INTERVENTION(S): Ovarian superovulation, follicle aspiration, sperm injection, and assisted follicular rupture. MAIN OUTCOME MEASURE(S): Assessment of feasibility of technique and pregnancy outcome. RESULT(S): After failing to conceive during 16 cycles of IUI, the patient successfully achieved an ongoing pregnancy during the second follicle aspiration, sperm injection, and assisted rupture (FASIAR) attempt. CONCLUSION(S): Follicle aspiration, sperm injection, and assisted rupture combines the concepts of superovulation, IUI, and peritoneal oocyte and sperm transfer to obviate the possibility of luteinized unruptured follicle syndrome, assist oocyte release, and ensure gamete intermixing. It also can be used to reduce the number of ovulating oocytes and thus to reduce the risk of multiple gestations. Follicle aspiration, sperm injection, and assisted rupture is a new, simple, office-based procedure that does not require embryologic expertise beyond sperm preparation as for IUI, yet promises to be more successful than IUI.

Adult↗
PubMed2002

GnRH antagonists: do they open new pathways to safer treatment in assisted reproductive techniques?

GnRH antagonists (GnRHnt) induce a rapid decrease in LH and FSH, preventing and interrupting LH surges. Their properties do not require a desensitization period and allow their use in the late follicular phase. GnRHnt could replace GnRH agonists (GnRHa) in ovarian stimulation without their side-effects and their long period of desensitivity. Both protocols using GnRHnt were associated with a smaller amount of gonadotrophin, a shorter stimulation period and a lower incidence of ovarian hyperstimulation syndrome (OHSS) with statistically comparable pregnancy rates. There is room for improvement of both protocols concerning the programming, the antagonist dose and the timing of antagonist administration. Luteal support should be maintained until the results of further studies. The perinatal outcome appears to be similar to that of other stimulation regimens. Triggering of ovulation can be facilitated by GnRHa for patients at risk of OHSS. Provided that pregnancy rates equivalent to those obtained with GnRHa are confirmed in larger series, GnRHnt will clearly represent a safer alternative to GnRHa protocols in IVF.

Female↗
PubMed1995

[Cytogenetic abnormalities in sperm: a risk factor for application of medical reproduction techniques?].

Microinsemination techniques are increasingly applied to achieve fertilisation of the oocyte in cases of male fertility disorders. Thus, spermatozoa can directly interact with the oolemma or the ooplasm, thereby obviating the need for penetration through cumulus oophorus and zona pellucida. However, problems associated with this particular feature arise in view of the following considerations: 1. The gametes from subfertile males are suspected to carry more cytogenetic anomalies in addition to an impaired sperm quality when compared to fertile men. 2. Cumulus and zona play an important role in the selection of morphologically abnormal and dysfunctional spermatozoa. 3. Consequently, bypassing natural sperm selection processes would lead to more abnormal embryos, abortions, and births of diseased or handicapped children. Spermatozoa can be analysed cytogenetically after fusion with zona-free hamster eggs or by fluorescence in situ hybridization (FISH). Both techniques did not confirm increased aberrations in gametes from subfertile men with a normal somatic karyotype. However, a definite conclusion cannot be drawn because of the limited data and restrictions concerning their interpretation. This also holds true for the evaluation of correlations indicating no significant relationship between the chromosomal constitution and sperm motility or morphology, respectively. Currently, the risk of malformation after microinsemination does not appear to be increased when compared to conventional IVF but the results do not yet allow a reliable statistical evaluation. In contrast, decreased morphological quality, impaired implantation, and early abortions have been reported for embryos produced by assisted fertilisation. This suggests that an effective natural selection of abnormal embryos will prevent a significant increase in malformations in the following generation.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Aberrations↗
PubMed2004

Is there a place for immunomodulation in assisted reproduction techniques?

We briefly review the history of the concepts of the materno foetal relationship, and the (various) rationales which have been used to justify lymphocyte alloimmunisation (LA) as a treatment for recurrent spontaneous abortion of putative immune origins. The effectiveness of the treatment is at best dubious and limited to a small number of women for which there is no real positive selection rationale, at worst it is not efficient. The rationales themselves are rather "evolutive". The present one is to use the Th1:Th2 paradigm and, thus, to propose to "dampen NK activity" in abortion prone women and this concept has been extended by some to implantation failure. We briefly review why the Th1:Th2 paradigms is no longer fully valid, describe briefly why it is inappropriate for implantation, and conclude that alloimmunisation should no longer be proposed for RSA, hence, more for implantation failure. We, however, do not reject immunotherapy, but we believe that molecular and cellular defects specific approaches should be used, tailored for the specific pathway whose disruption cause the clinical symptom.

Abortion, Spontaneous↗
PubMed2002

[Contribution of ovarian and uterine color Doppler in medically assisted reproduction techniques (ART)].

Along the menstrual cycle and during pregnancy, small blood vessels proliferate within the uterus and the ovulating ovary. Angiogenic factors such as VEGF are involved in this phenomenon. In the ovulating ovary, neo-angiogenesis spreads progressively inside the dominant follicle wall and plays a role in the maintenance of the corpus luteum, under the influence of LH (or HCG during pregnancy). In ART, the measure of the blood flow is interesting since it correlates to the number and quality of harvested oocytes. Follicle hypoxia may impair chromosomal organization and separation within the oocyte. This neo-angiogenesis is also important in endometrium, in particular for embryo implantation. Ultrasounds with Doppler allow to estimate the endometrial receptivity, especially in IVF cycles. It is assumed that chance for ongoing pregnancy is almost zero if: endometrial thickness is < 8 mm; uterine pulsatility index (PI) is > 3. Doppler ultrasounds are a useful and even mandatory complement to standard vaginal ultrasonoghraphy in ART. It can be viewed as an indicator of the endometrial and follicular "well-being".

Endometrium↗
PubMed2006

[How to improve assisted reproductive techniques results? Biological aspects].

In spite of recent improvements in IVF, pregnancy rates remained dramatically low. Better criteria are therefore necessary to establish the viability of a transferable top quality embryo. Observation of both pronuclei patterns at the zygote stage and early cleavage appears to offer an additional prognostic tool, correlating with chromosomal status and IVF outcome. Developmental ability and morphological evaluation of the embryo on days 2-3 remains the most used and valid method of selection, even though it is not sufficient to select embryos with the higher implantation potential. Blastocyst culture is another possible strategy for selecting the ideal embryo with theoretical, reduced risk of aneuploidies, though not all major chromosomal aberrations are excluded by prolonged in-vitro-culture. Concerning micro-manipulation of embryo such as hatching or cleaning or cytoplasm transfer, only controversial data are still available. In the field of ART, recent meta-analysis could not conclude to a positive effect concerning hatching, blastocyst culture or systematic PGD-AS (preimplantation genetic diagnosis with aneuploidy screening). Beside the technological aspect, Quality Management System is of great importance. Staff development and monitoring of staff performance in the IVF laboratory has to be considered in the next future.

Blastocyst↗
PubMed2006

[DNA sperm methylation in assisted reproductive techniques].

In the last few years, many tests were developed to study the fertilizing properties of the spermatozoa. However none of them was useful to obtain a prognostic factor. Indeed, the integrity of the spermatic DNA is also necessary to a successful fertilization for obtaining a pregnancy. DNA integrity could be evaluated by the measurement of the level of DNA methylation. Indeed, in the mammals, the methylation of the ADN is involved in diverse processes amongst them the regulation of the genome expression during the embryonic development. The objective of this study is to evaluate the impact of the level of methylation of the spermatic DNA in the success of in vitro fertilization (IVF), in terms of rate of fertilization, quality of the embryos and rate of pregnancy. The immunostaining of the 5-methylecytosine, then the quantification by image analysis or with flow cytometry, allowed an objective evaluation of the level of total methylation of spermatic DNA. Our data show that the level of DNA methylation influences neither the fertilization rate nor the embryos quality. On the other hand, the rate of pregnancy is decreased if the total level of DNA methylation is lower than a threshold value. The level of spermatic DNA methylation represents a new parameter of spermatic maturation.

5-Methylcytosine↗
PubMed2003

[Cumulus cell apoptosis as a predictor for oocyte quality in artificial reproduction technique].

OBJECTIVE: To be able to predict the success of ART reliable tests for determining the quality of the oocytes are necessary. Apart from a vague morphologic assessment via microscopy a direct analysis of the oocyte quality is not possible. Because of the very close relation between the oocyte and the cumulus cells the analysis of the cumulus cells might give sufficient information on the oocyte quality. In this study we correlate the apoptotic activity of cumulus cells to the outcome of fertilized oocytes after Intracytoplasmic Sperm Injection (ICSI). MATERIAL AND METHODS: 246 cumulus-oocyte-complexes from patients undergoing infertility treatment with the ICSI procedure were individually collected. The comet assay was used to determine the proportion of apoptotic cells within the cumulus population of each oocyte and correlated with oocyte fertilization and oocyte quality as well as with pregnancy outcome in 86 patients. RESULTS: We were able to show that high quality embryos correlate to a low rate of apoptotic cells in their corresponding cumuli. Differences regarding the pregnancy outcome were statistically not significant. CONCLUSIONS: Our results on cumulus cell apoptosis and embryo quality confirm other publications. To arrive at statistically proven criteria for the further development of single oocytes an increase in the number of analyzed patients is necessary.

Apoptosis↗
PubMed2001

Assisted reproductive techniques for hybridization of camelids.

The camelid family comprises the Old World camelids (or dromedary and Bactrian camels) and the New World camelids (namely the llamas, alpacas, guanacos and vicunas). Although the species within each group can hybridize among themselves to produce fertile offspring, it is only recently that a hybrid between New and Old World camelids has been reported. To create this hybrid, semen was collected from male camels by artificial vagina (AV) and inseminated into female guanacos (n = 9) and llamas (n = 3) at the appropriate stage of their follicular wave cycle. Similarly, guanaco and llama semen was collected, also by AV, and inseminated into female camels (n = 42). Although several conceptions occurred, only one hybrid (camel sire x guanaco dam) continued to term and was born alive after 328 days of gestation, and another is pregnant at the time of writing (camel sire x llama dam). Further studies are presently being carried out using extraspecific embryo transfer to try and improve the success rate of live offspring being born. Female guanacos (n = 4) are treated with hormones to stimulate their ovaries to produce several follicles before being inseminated with camel semen. Of the 12 camel recipients that have to date received hybrid embryos (camel sire x guanaco dam), 10 conceived, but 9 of these subsequently aborted between 30 and 365 days and only one recipient was still pregnant at the time of writing.

Abortion, Veterinary↗
PubMed2000

Preimplantation diagnosis after assisted reproduction techniques for genetically-determined male infertility.

One hundred and thirty-six cycles with a poor prognosis for full-term pregnancy underwent preimplantation genetic diagnosis (PGD) of aneuploidy. The mean maternal age was 31.8 +/- 2.5 years. Only patients younger than 36 years were included in the study with the aim of evaluating whether sperm indices have an effect on the chromosomal constitution of preimplantation embryos. No differences were detected in the percentage of aneuploid embryos; however a higher incidence of monosomies and trisomies was found in MESA-TESE embryos compared to the group of normospermic patients. In addition, an increase in the proportion of gonosomal aneuploidy seemed to be associated with the severity of the male factor parameters. The rate of de-novo chromosomal abnormalities in embryos from patients with a normal karyotype suggested an increased frequency proportional to the severity of the male factor condition, the proportion of monosomic and trisomic embryos, and the percentage of gonosomal aneuploidy increased accordingly. In the case of couples with a male altered karyotype, comparable frequency of chromosomally abnormal embryos, and monosomy and trisomy were observed irrespective of semen indices, gonosomal aneuploidy was only observed in one case where the patient had a karyotype with gonosomal mosaicism. These data confirm that the severe male infertility condition determines an increase in the rate of de-novo abnormalities, as anticipate by the follow-up of the children born after ICSI.

Adult↗
PubMed2003

Patterns of intracellular calcium oscillations in horse oocytes fertilized by intracytoplasmic sperm injection: possible explanations for the low success of this assisted reproduction technique in the horse.

In all species studied, fertilization induces intracellular Ca2+ ([Ca2+]i) oscillations required for oocyte activation and embryonic development. This species-specific pattern has not been studied in the equine, partly due to the difficulties linked to in vitro fertilization in this species. Therefore, the objective of this study was to use intracytoplasmic sperm injection (ICSI) to investigate fertilization-induced [Ca2+]i signaling and, possibly, ascertain problems linked to the success of this technology in the horse. In vivo- and in vitro-matured mare oocytes were injected with a single motile stallion sperm. Few oocytes displayed [Ca2+]i responses regardless of oocyte source and we hypothesized that this may result from insufficient release of the sperm-borne active molecule (sperm factor) into the oocyte. However, permeabilization of sperm membranes with Triton-X or by sonication did not alleviate the deficient [Ca2+]i responses in mare oocytes. Thus, we hypothesized that a step downstream of release, possibly required for sperm factor function, is not appropriately accomplished in horse oocytes. To test this, ICSI-fertilized horse oocytes were fused to unfertilized mouse oocytes, which are known to respond with [Ca2+]i oscillations to injection of stallion sperm, and [Ca2+]i monitoring was performed. Such pairs consistently displayed [Ca2+]i responses demonstrating that the sperm factor is appropriately released into the ooplasm of horse oocytes, but that these are unable to activate and/or provide the appropriate substrate that is required for the sperm factor delivered by ICSI to initiate oscillations. These findings may have implications to improve the success of ICSI in the equine and other livestock species.

Animals↗
PubMed2004

The results of aneuploidy screening in 276 couples undergoing assisted reproductive techniques.

Preimplantation genetic diagnosis for aneuploidy screening (PGD-AS) using sequential in situ hybridization was applied for aneuploidy testing in 276 couples with 282 ART cycles. Patients with advanced maternal age (AMA, n = 147), recurrent implantation failure (RIF, n = 48), repeated early spontaneous abortion (RSA, n = 32) and abnormal gamete cell morphology (AGCM, n = 55) including macrocephal sperm forms or cytoplasmic granular oocytes were included. Embryo biopsy was performed on day 3 in a calcium-magnesium-free medium by using a noncontact diode laser system. After fixation and enzymatic treatment, fluorescent in situ hybridization (FISH) was carried out on 1147 blastomeres with specific probes for chromosomes 13, 16, 18, 21 and 22 for AMA group, 13, 18, 21, X and Y for AGCM group and 13, 16, 18, 21, 22, X and Y for RIF and RSA groups respectively. The overall chromosomal abnormality rate in analyzed embryos was 40.9%, with no significant difference between AMA, RIF and RSA groups (p > 0.05). However, AGCM group presented a higher rate of chromosomal aneuploidies (57.4%) than the other three groups (p < 0.01). A total of 84% biopsied embryos presented cleavage in 24 h and embryo transfer was realized in 278 cycles. In four cycles, no chromosomally normal embryo was found for embryo transfer. A total of 88 pregnancies (31.6%) were achieved, 19.3% resulted in abortion and 63 healthy births were obtained, with a total of 93 babies born. Aneuploidy testing in couples with poor prognosis undergoing ART cycles is a useful tool to increase the chance of ART success. Furthermore, abnormal gamete cell morphology should be considered one of the major indications for PGD in ART programs as high aneuploidy rates were observed in this group.

Abortion, Habitual↗
PubMed1999

Aggressive perinatal care for high-order multiple gestations: Does good perinatal outcome justify aggressive assisted reproductive techniques?

OBJECTIVE: The purpose of this study was to determine the factors that must be considered for appropriate counseling of patients with high-order multiple gestations. STUDY DESIGN: A retrospective chart review was carried out from all high-order multiple gestations that were managed by a single perinatology group from February 1993-June 1998. Twin pregnancies that did not result from fetal reduction procedures were used as a control group. RESULTS: Clinical outcome data were analyzed from 9 quadruplet, 25 triplet, 19 reduced twin, and 24 nonreduced twin pregnancies. Women with quadruplet pregnancies were admitted more frequently at an early gestational age, the infants were delivered earlier, and the maternal and neonatal hospital days were longer than for triplet and reduced and nonreduced twin gestations. Triplet pregnancies had an earlier gestational age at delivery (32.3 vs 34.2 weeks), a higher incidence of preterm labor (87% vs 68%), and a higher percentage of neonatal intensive care unit admissions (94% vs 59%) than reduced twin gestations. Reduced twins were hospitalized longer (16.4 vs 9.8 days), were delivered earlier (34.2 vs 36.2 weeks), had a higher incidence of preterm labor (68% vs 29%), and had a greater percentage of neonatal intensive care unit admissions (59% vs 21%), a greater percentage of birth weight <1500 g, and a greater frequency of respiratory distress syndrome (16% vs 2%) than nonreduced twins. There was no difference in neonatal survival and neurologic morbidity when all groups were compared. CONCLUSION: Although early delivery and prolonged (maternal and neonatal) hospitalization were common with quadruplets and triplets, maternal and neonatal outcomes were excellent. The decision for reduction from triplets to twins may not necessarily change pregnancy outcome but should still be discussed as an option for the parents. Continued efforts need to be made to reduce the overall number of iatrogenic high-order multiple gestations.

Female↗
PubMed2000

Recent trends in assisted reproductive techniques and associated outcomes.

OBJECTIVE: We examined recent trends in success rates for assisted reproduction and determined the influence of changes in patient selection and treatment characteristics on these trends. METHODS: We collected baseline information and abstracted treatment-related details and outcomes on 1244 couples accepted for in vitro fertilization (IVF) or gamete intrafallopian transfer (GIFT) at three clinics in greater Boston from 1994-1998. RESULTS: Delivery rates per initiated cycle improved significantly from 14.9% for IVF and 20.6% for GIFT in 1994-1995 to 22.5% for IVF and 28.0% for GIFT in 1997-1998 (P < or = .001). After adjusting for female age, the two treatment-related variables that appeared most likely to explain this trend were decreased use of GnRH agonists in short course (flare) regimens and increased use of highly purified forms of urinary gonadotropins. CONCLUSION: There were significant improvements in the success rates for IVF and GIFT from 1994-1998 that correlated with changes in ovulation induction regimens.

Adult↗
PubMed2000

Evaluation of a reproduction technique for the study of the enamel composite/bracket base area.

The objective of the study was to evaluate a reproduction method that would enable the study of the enamel/ bracket/composite interface in vivo, and consisted of in vitro assessment of two different impression materials to compare reproduction of brackets bonded to extracted teeth followed by in vivo assessment of the superior material. In vitro standard edgewise brackets were bonded to two extracted teeth and impressions were taken using two different types of low viscosity silicone-based impression materials. A medium viscosity silicone impression material was used to support the original impression. Three impressions of both the gingival and occlusal aspect of the bracket base region were obtained using each of the impression materials. Replicas were then prepared for SEM viewing and these compared to SEMs of the real teeth for reproduction of detail. A 3-point Reproducibility Index was used to compare the SEM photographs of the comparable replicas. One impression material was clearly superior to the other and produced an acceptably accurate representation of the true clinical situation in three out of four samples. This material also performed well in the in vivo situation. The technique described is satisfactory for the production and analysis of SEM pictures of the enamel/composite/ bracket base interface in vivo.

Acrylic Resins↗
PubMed2001

Results of assisted reproduction techniques in Latin America.

The fact that today it is possible to write a comprehensive report on assisted reproduction technologies in Latin America is the result of a serious and systematic effort, accomplished by more than 80 centres, from Mexico to Chile. Over the past 10 years, these centres representing the vast majority of assisted reproductive treatment cycles performed in Latin America, have agreed voluntarily to report their work to our regional registry using a pre-established format. Furthermore, during 1999 and part of 2000, all centres were visited by a team of biologists and clinicians, who evaluated for consistencies in the data reported. This activity also included an evaluation of personnel, facilities, etc. It can be proudly said that the data reported are a true reflection of the actual situation in our region.

Journal Article↗