Biomedical subjects

Anne-Sophie Vannin

Publications and source records attributed to Anne-Sophie Vannin.

5 recordsLinked to original sources

PubMed2006

Development and evaluation of a qualitative reverse-transcriptase nested polymerase chain reaction protocol for same-day viral validation of human immunodeficiency virus type 1 ribonucleic acid in processed semen.

OBJECTIVE: To develop a method for same-day validation of processed semen in the setting of assisted reproductive techniques (ART) with patients who are seropositive for human immunodeficiency virus, type 1 (HIV-1). DESIGN: Laboratory experiments. SETTING: University hospital. PATIENT(S): Volunteers who are HIV-1 seronegative and seropositive. INTERVENTION(S): Evaluation of the sensitivity of a reverse-transcriptase (RT)-nested polymerase chain reaction (PCR) in HIV-1 RNA-positive blood plasma, in artificially infected blood plasma and semen, and in 85 semen samples of 29 HIV-1-seropositive volunteers. Semen was submitted to gradient separation, followed by swim-up. MAIN OUTCOME MEASURE(S): Qualitative detection of HIV-1 RNA in blood plasma and in different parts of semen preparation by using RT-nested PCR, PCR inhibition control by dilution of samples, and an internal control. RESULT(S): The detection limit of our PCR was 20 HIV-1 RNA copies per milliliter. Among seropositive patients, RNA was detected in 25% of fresh semen, 36.5% of seminal plasma, 27.5% of gradient supernatants, and 7.1% of final preparations before the migration-sedimentation stage. Positive final preparations were observed in patients who had blood viral loads of >/=20,000 HIV-1 RNA copies per milliliter. Inhibition was present in 17.6% of seminal plasma and in 20% gradient supernatants and in 2 final preparations among 69 tested. Among 25 preparations tested after the migration-sedimentation stage, 2 were positive (1 patient; 70,000 HIV-1 RNA copies per milliliter). CONCLUSION(S): The RT-nested PCR detects low viral load and allows the validation of semen preparations of HIV-1-seropositive patients for ART on the day of sampling. For this purpose, the validation is performed on spermatozoa that are obtained after gradient separation before swim-up. Inhibition of the PCR must be controlled by using an internal control that is well-designed to explore the detection limit of the method.

Cells, Cultured↗

PubMed2006

Impact of the assessment of early cleavage in a single embryo transfer policy.

The policy of single embryo transfer (SET) adopted for women <36 years old since 1 July 2003, strongly calls for improvement of embryo selection. A total of 196 cycles in which SET was performed were randomly allocated to two groups. In the first group, early cleavage was assessed (ECA) 25 h after insemination. The embryo with the best score that cleaved early, if present, was selected for transfer. In the second group, early cleavage was not assessed (ECNA) and embryo selection was based solely on the embryo score. Ninety-eight cycles were allocated in the ECA and ECNA group respectively. Early cleavage occurred in 64% of cycles and 32.2% of embryos. Patient population and embryo morphology were similar between the two groups, and similar delivery rates were observed (27.6 versus 24.5% respectively in the ECA and ECNA groups). The assessment of early cleavage as additional parameter did not improve the delivery rate in the single embryo transfer policy.

Adult↗

PubMed2003

Incidence of chromosomal mosaicism in human embryos at different developmental stages analyzed by fluorescence in situ hybridization.

Chromosomal mosaicism has been reported in in vitro-cultured embryos at early cleavage stages, as well as in morulae and blastocysts. We have assessed the incidence and pattern of mosaicism during in vitro development of human embryos from early-cleavage stages to morula and blastocyst. Fifty spare embryos were fixed for fluorescence in situ hybridization (FISH) analysis for chromosomes X, Y, 13, 18, and 21 on days 2 or 3 (4- to 10-cell stage) (n = 16), on day 4 (morula stage) (n = 14), on day 5 (pre-expanded blastocyst) (n = 5), and the expanded blastocyst stages (n = 15). Blocked embryos (no cleavage observed within the last 24 hr) were not included. A total of 2367 cells were analyzed. Four early-cleavage stage embryos were found uniformly diploid; all of the others were mosaic for the chromosomes analyzed (mean diploid nuclei 48.3% +/- 28.7). All of the embryos at more advanced developmental stages, except one fully normal morula, had mosaic chromosome constitutions, with an increase in the percentage of diploid cells in morulae, pre-expanded, and expanded blastocysts, respectively (mean diploid nuclei 78.6% +/- 11.7, 66.0% +/- 20.8, 79.6% +/- 12.8), in comparison with earlier stages. Hypotheses about the origin of mosaicism and embryo regulation mechanisms will be discussed.

Aneuploidy↗

PubMed2003

Similar delivery rates in a selected group of patients, for day 2 and day 5 embryos both cultured in sequential medium: a randomized study.

BACKGROUND: The existence of a real benefit of blastocyst transfer is still a matter of debate. The aim of this study was to compare, in a prospective randomized trial, the outcome of day 2 and day 5 transfer of human embryos cultured in an 'in-house' sequential medium. METHODS: A total of 193 cycles from 171 patients with less than four previous IVF cycles, <39 years old and with four or more zygotes on day 1, were randomly allocated to day 2 (94 cycles) or day 5 (99 cycles) transfer. Zygotes were kept in fertilization medium until 18 h post-fertilization and then placed in a 'glucose-free' cleavage medium. Embryos allocated for day 5 transfer were placed in a blastocyst medium 66 h post-fertilization. Two or three embryos were replaced according to the morphology. RESULTS: A mean (+/- SEM) number of 2.1 +/- 0.4 and 1.9 +/- 0.3 embryos were replaced on day 2 and day 5 (P < 0.001) respectively. Delivery rates per transfer were 44.1 and 37.1% [P = not significant (NS)], implantation rates were 31.4 and 29.4% (NS) and multiple delivery rates 22 and 36% (NS) for day 2 and day 5 groups respectively. Ten patients (10.1%) had no blastocysts available for transfer. CONCLUSIONS: No clear benefits were observed using blastocyst transfer for patients aged <39 years who had had less than four previous IVF cycle attempts.

Adult↗

PubMedDate not supplied

Medically assisted reproduction in the presence of chronic viral diseases.

Teams practising medically assisted reproduction techniques try to avoid viruses as much as possible. Attitudes towards chronic carriers of viruses are rapidly changing, especially for human immunodeficiency virus (HIV) patients. We focus our attention on the legitimacy of systematic screening before assisted reproductive techniques and the need for specialized approaches including an adapted laboratory for viral hazards as well as the need for a multidisciplinary team. Specificities of HIV, hepatitis C virus (HCV), hepatitis B virus (HBV) carriers and the hypothesis of a reduced fertility potential are discussed. Are male HIV carriers a new indication for assisted reproductive techniques in order to prevent virus transmission? It is largely proven that sperm gradient preparation techniques efficiently decrease viral loads and therefore have a protective effect on contamination risk during assisted reproductive techniques. Although a few thousand assisted reproductive technique cycles were performed in the world for this indication without contamination, it is still too early to demonstrate that this technology is fully safe. Two examples of contaminations during insemination are examined. Many questions remain unresolved, such as the lack of standardized techniques for semen preparation or virus detection or the relative merits of intrauterine insemination or ICSI to prevent HIV contamination during assisted reproductive techniques. The authors plead for well-structured, separate programmes of care linked to research objectives.

Acquired Immunodeficiency Syndrome↗