Microbial contamination of embryo cultures in an ART laboratory: sources and management.

BACKGROUND: Although rare, microbial contamination of culture dishes occasionally occurs in our IVF/ICSI programme. Despite stringent culture conditions and the use of medium containing penicillin and streptomycin, an increasing number of infections was observed once they were routinely recorded. In this study, 95 cases of contaminated culture dishes were examined, in an attempt to identify possible causes. METHODS: Relevant data of the IVF/ICSI treatment cycles and the micro-organisms isolated from the infected culture dishes were evaluated retrospectively. RESULTS: Infections were observed only in IVF culture dishes and never after applying intra-cytoplasmic sperm injection. Identification of the contaminating micro-organisms showed that infections were mainly caused by Escherichia coli (n = 56; 58.9%) and Candida species (n = 24; 25.3%). Of the E. coli strains isolated, 41 (73.2%) appeared to be resistant to both antibiotics used in the culture medium and 13 (23.2%) appeared to resist either penicillin or streptomycin. Of all bacterial strains isolated, the resistances were 61.4% to both and 30% to one of the antibiotics used. CONCLUSIONS: Applying the ICSI procedure prevents colonization of the culture dishes by micro-organisms. Infections in IVF culture dishes are mainly caused by bacterial strains insensitive to the antibiotics used or due to yeast colonization by Candida species which frequently reside in the vagina.

A case study of the applicability of a prediction model for the selection of patients undergoing in vitro fertilization for single embryo transfer in another center.

OBJECTIVE: To evaluate the application in a different fertility clinic of a prediction model for selecting IVF patients for elective single embryo transfer. DESIGN: Retrospective analysis of a large database obtained from a tertiary infertility center. SETTING: University medical center. PATIENT(S): The model, derived at the "development center" was applied in 494 consecutive first IVF cycles carried out at the "application center." INTERVENTION(S): After adjustment of embryo scoring system to be compatible with that used by the prediction model, it was applied to the development center data. A score chart for predicting the probability of singleton or twin pregnancy was constructed. MAIN OUTCOME MEASURE(S): The area under the receiver operator curve (ROC) was determined to measure the ability of the model to discriminate between ongoing pregnancy and twin pregnancy. Calibration plots were made to assess agreement between predicted and observed pregnancy rates (PR). RESULTS: The areas under the ROC for predicting ongoing pregnancy and twin pregnancy were 0.63 and 0.66, respectively. Insertion of a correction factor equivalent to the difference in odds ratios for ongoing PR between the two centers was required to improve the calibration of the model. CONCLUSION(S): After adaptation, the model performed well in the application center.

FSH receptor genotype is associated with pregnancy but not with ovarian response in IVF.

Two very common single nucleotide polymorphisms at positions 307 and 680 in exon 10 of the FSH receptor gene have been associated with ovarian response in IVF. This observational study evaluated the role of the FSH receptor genotype in the prediction of poor response and clinical pregnancy in IVF in comparison with other markers, such as age, basal FSH, anti-Müllerian hormone and antral follicle count. In addition, the in-vitro cAMP response towards recombinant FSH in cultured granulosa cells of patients with different FSH receptor genotypes was determined. A total of 105 IVF patients undergoing ovarian stimulation in a long suppression protocol were included in the study. The ovarian response was comparable between patients with different FSH receptor genotypes. Patients with polymorphism Ser/Ser had implantation and pregnancy rates that were three times higher compared with patients with polymorphism Asn/Asn. FSH receptor genotype was not associated with a poor response in IVF, but showed a positive association with pregnancy, independent of age. There was no difference in cAMP production in cultured granulosa cells of patients with different FSH receptor genotypes (n=62). It is concluded that FSH receptor genotype is associated with pregnancy in IVF, but not with ovarian response.

A high number of oocytes obtained after ovarian hyperstimulation for in vitro fertilization or intracytoplasmic sperm injection is not associated with decreased pregnancy outcome.

OBJECTIVE: To investigate the possible negative effects of a strong ovarian response on oocyte quality. DESIGN: Retrospective study. SETTING: Tertiary academic center. PATIENT(S): A total of 1,894 women (IVF, n = 1,544; ICSI, n = 350) who underwent their first ovarian stimulation cycle during the period 1995-2002. INTERVENTION(S): Standardized controlled ovarian stimulation with urinary FSH or recombinant FSH after pituitary down-regulation, followed by IVF/intracytoplasmic sperm injection (ICSI) and ET. MAIN OUTCOME MEASURE(S): Fertilization rate, fraction of high-quality embryos, and implantation rate. RESULT(S): Using multivariate logistic regression, we analyzed the effect, expressed as an odds ratio (OR), of the number of oocytes obtained (i.e., ovarian response) on the outcome measures. No effect of the response on the ongoing implantation rate or fraction of high-quality embryos was observed. Both in IVF (OR = 0.81, 95% confidence interval [CI] 0.75-0.87) and in ICSI (OR = 0.88, 95% CI 0.76-1.00), a negative effect of increasing ovarian response was seen on the fertilization rate per oocyte obtained. However, no negative effect was observed on the fertilization rate per oocyte injected in ICSI (OR = 1.00, 95% CI 0.87-1.14). The fraction of immature oocytes rises from 3.9%, in women with < or = 3 oocytes, to 26% in women with > 20 oocytes. CONCLUSION(S): Oocytes from high responders contain a greater fraction of immature oocytes, but pregnancy outcome is not impaired.

Human embryonic stem cells: towards therapies for cardiac disease. Derivation of a Dutch human embryonic stem cell line.

Cell transplantation is being discussed as a potential therapy for multiple disorders caused by loss or malfunction of single or at most a few cell types. These include diabetes, Parkinson's disease and myocardial infarction or cardiac failure. However, it is not yet clear whether cells from adult tissues ('adult stem cells') or embryos ('embryonic stem cells') will prove to be the most appropriate replacement cells; most likely, each disease will have its own preferred source. This study presents the background to this discussion and the current state of research in replacement of cardiac tissue, with focus on recent developments using human embryonic stem cells. It also describes a new human embryonic stem cell (HESC) line, NL-HESC1, the first to be derived in the Netherlands, and shows that it forms cardiac cells in a manner comparable with that of hES2 and hES3 cells grown in the same laboratory.