Importance of a 5- versus 7-day pill-free interval in a GnRH antagonist protocol using corifollitropin alfa: a prospective cohort study in oocyte donors.

In this prospective cohort study, oocyte donors were recruited prospectively and assigned to receive corifollitropin alfa: 5 days after pill discontinuation (group D5; 42 donors), or 7 days after pill discontinuation (group D7; 50 donors) in a gonadotrophin-releasing hormone antagonist protocol. Fixed additional daily doses of 200 IU recombinent FSH (rFSH) were started after 7 days of corifollitropinalfa, until triggering. No significant differences in basal characteristics were observed between both groups. In group D5, mean (SD) total additional rFSH dose was 659 (452) IU; in group D7, total rFSH dose was 459 (356) IU (P = 0.022). Duration of stimulation was significantly longer in group D5 compared with group D7 (P = 0.002). No differences were found in total number of oocytes obtained. Total number of injections was significantly lower in group D7 compared with group D5 (9.8 [3.2] versus 11.9 [3.9], respectively; P = 0.004). Total cost of medication used for donor treatment was significantly higher in group D5 than in group D7 (P = 0.015). After more than 22 days of pill-taking, extending the pill-free interval to 7 days significantly reduces the total dose of gonadotrophins, duration of stimulation, total cost of medication and total number of injections.

Is AMH useful to reduce low ovarian response to GnRH antagonist protocol in oocyte donors?

We aimed to establish the reference values of Anti-Müllerian hormone (AMH) in our oocyte donor population and correlate them with the ovarian response to an antagonist stimulation protocol and to study the predictive capacity of AMH for poor response (PR). Normal AMH curves were obtained for 172 candidates. AMH levels decreased with age although they showed great heterogeneity and spread in absolute values at any age range. AMH levels showed a positive correlation, statistically significant, with the Antral Follicle Count (r = 0,705), and number of oocytes retrieved (r = 0,356). In receiver operating characteristic curve analysis a threshold value of AMH = 2.31 ng/ml predictive for retrieval <6 MII (area under the curve (AUC) 0.675) was identified. This cut-off predicted PR with a sensitivity of 70.4% and a specificity of 61.8%, (PPV = 39.6%; NPV = 85.5%, p = 0.004). When performing a multiple logistic regression analysis including age, AFC and FSH, an AUC = 0.668 for PR was obtained whereas if AMH was added to the model it resulted in an AUC = 0.713. In oocyte donors aged 18 to 35 with an AFC ≥ 10 and basal FSH <10 mIU/ml, measuring AMH levels improved just slightly the prediction for PR.

Vitrified blastocysts from Preimplantation Genetic Diagnosis (PGD) as a source for human Embryonic Stem Cell (hESC) derivation.

Embryos diagnosed as abnormal in Preimplantation Genetic Diagnosis (PGD) cycles are useful for the establishment of human Embryonic Stem Cells (hESC) lines with genetic disorders. These lines can be helpful for drug screening and for the development of new treatments. Vitrification has proved to be an efficient method to preserve human blastocysts. One hundred and three abnormal or undiagnosed vitrified blastocysts from the PGD programme at Institut Universitari Dexeus were donated for human embryonic stem cell derivation. The overall survival rate after warming was 70.6 %. Our results showed better survival rates when blastocysts have not started the hatching process (initial/expanded 87.8 %, hatching 68.3 % and hatched 27.3 %). Thirty-five blastocysts and 12 partially surviving embryos were seeded. One hESC line with the multiple exostoses type 2 paternal mutation was obtained.

Triggering ovulation with 250 µg or 500 µg of r-hCG in oocyte donors treated with antagonist protocol has no effect on the number of mature oocytes retrieved: a randomized clinical trial.

The aim of this study is to compare two r-hCG doses to trigger ovulation (250 µg vs. 500 µg of r-hCG) in an oocyte donation program. A prospective, randomized study was conducted in 118 oocyte donors. Group DI received 250 µg and Group DII received 500 µg of r-hCG. Both the groups were homogeneous. No significant differences were found in the total dose of gonadotropins, duration of the treatment, total number of oocytes, or Metaphase II (MII)oocytes. The pregnancy rate per embryo transfer in the corresponding recipients was similar for both the groups (58.2% for DII recipients and 56.1% for DI recipients). Mild hyperstimulation was observed in 17 donors in Group DI (29%) and in 23 donors in Group DII (39%). No cases of severe ovarian hyperstimulation syndrome (SOHSS) were observed. In conclusion, a double dose of r-hCG in oocyte donors to trigger ovulation after stimulation with r-FSH and antagonist does not translate into a higher number of MII oocytes retrieved or into higher pregnancy rates among recipients. Our results confirm that the optimal dose to induce the final oocyte maturation with r-hCG is 250 µg, and that a higher dose does not add any benefit.

Correlation between embryological factors and pregnancy rate: development of an embryo score in a cryopreservation programme.

PURPOSE: To establish which embryo parameters, in frozen thawed embryo transfers, have the highest prognosis value in the establishment of pregnancy. The relative importance of different embryo parameters is used to develop an embryo score. METHODS: Retrospective analysis of the implantation rate in 356 frozen/thawed single embryo transfers. A logistic regression model is used to establish an embryo score. RESULTS: A direct correlation is established between the implantation rate and fresh embryo development (number of blastomeres and their symmetry), survival rate after thawing and mitosis resumption after overnight culture. CONCLUSIONS: An embryo score is developed to determine the implantation potential of frozen/thawed embryos.

Analysis of factors associated with multiple pregnancy in an oocyte donation programme.

The aim of this study is to identify the factors associated with multiple pregnancy in an oocyte donation programme. A retrospective study (2000-2007) of 945 synchronous cycles was performed. Two embryos were transferred in all cycles on day 2 after oocyte retrieval. All variables (egg donor and recipient age, number of inseminated oocytes, fertilized oocytes, cleaved embryos, good-quality embryos available, good-quality embryos transferred and frozen embryos) were analysed in relation to the clinical pregnancy rate per transfer (PR) and the multiple pregnancy rate (MPR). The donor age was 26.8±4.5 years and recipient age was 41.0±5.4. The number of good-quality embryos per recipient was 3.1±2.5. The PR was 55.1% and the MPR 36.5%. The number of good-quality embryos transferred (2 versus 0) was significantly associated (P<0.05) with the PR (60.6% versus 43.5%). The relationship between the MPR and the number of good-quality embryos transferred was adjusted by donor and recipient's age. For those patients who received 2 versus 0 good-quality embryos, the odds ratio of a multiple pregnancy was 2.1 (95% CI 1.121-3.876). The only predictive factor for multiple pregnancies in an oocyte donation programme is the quality of the transferred embryos. Since the development of assisted reproduction techniques, most countries have witnessed increased rates of multiple pregnancy. In IVF/intracytoplasmic sperm injection, effective strategies must be established to prevent multiple pregnancy without reducing overall pregnancy rates. In oocyte donation programmes, there is less awareness about the related risks. Actually, a minimum of two embryos are still transferred in most centres. The patient's age is higher and this fact implies more obstetric and perinatal complications. The aim of this study is to identify the factors associated with multiple pregnancy to contribute to establish future guidelines to avoid those risks.

Derivation of human embryonic stem cells at the Center of Regenerative Medicine in Barcelona.

We report here the legislative issues related to embryo research and human embryonic stem cell (hESC) research in Spain and the derivation of nine hESC lines at the Center of Regenerative Medicine in Barcelona. You can find the information for obtaining our lines for research purposes at blc@cmrb.eu.

Outcome of intracytoplasmic sperm injection in relation to the meiotic pattern in patients with severe oligoasthenozoospermia.

OBJECTIVE: The aim of the study was to evaluate the intracytoplasmic sperm injection outcome in a selected group of patients with oligoasthenozoospermia in relation to the results obtained from their meiotic analysis. DESIGN: Retrospective clinical study. SETTING: An assisted reproduction service and a university department. PATIENT(S): One hundred thirty-seven men with oligoasthenozoospermia grouped in relation to their meiotic pattern. INTERVENTION(S): Two hundred twenty-four intracytoplasmic sperm injection cycles from 137 men with oligoasthenozoospermia in whom diagnostic meiotic analyses had been performed. MAIN OUTCOME MEASURE(S): Fertilization, pregnancy, implantation, and abortion rates. RESULT(S): There were no significant statistical differences in fertilization, pregnancy, implantation, or abortion rates among the three groups studied. CONCLUSION(S): No statistically significant differences in fertilization, pregnancy, implantation, or abortion rates were found in patients with oligoasthenozoospermia in relation to the meiotic pattern.

Spermatogenic patterns and early embryo development after intracytoplasmic sperm injection in severe oligoasthenozoospermia.

PURPOSE: Evaluate the influence of different baseline spermatogenic patterns [meiotic pattern (normal or abnormal), sperm concentration (> 1 x 10(6)/mL or < or = 1 x 10(6)/mL), and the combined meiosis-sperm concentration pattern] on early embryo development in severe oligoasthenozoospermia. METHODS: Embryo outcomes (fertilization rate, cleavage rate, and 4-cell stage embryo division rate on day 2) after IVF-ICSI in 75 oligoasthenozoospermia and 79 normozoospermic males. RESULTS: The embryo division rate was significantly lower in oligoasthenozoospermia compared to normozoospermia (50.43% vs. 58.72%, p < 0.01) and in the oligoasthenozoospermia group for meiotic anomalies (43.40%), sperm concentration < or = 1 x 10(6)/mL (44.35%), and the combined pattern < or = 1 x 10(6)/mL with meiotic anomalies (37.17%). Logistic regression analysis showed a synergic effect (OR = 2.00; 95% CI = 1.28-3.12) when the two spermatogenic patterns predictive of slow embryo development [meiotic anomalies (OR = 1.49; 95% CI = 1.03-2.15) and sperm concentration < or = 1 x 10(6)/mL (OR = 1.53; 95% CI = 1.09-2.13)] were present. CONCLUSIONS: The data suggest that the early embryonic developmental capacity is inversely related to the severity of spermatogenic impairment (meiotic anomalies and/or sperm concentration < or = 1 x 10(6)/mL).

A confocal microscopy analysis of the spindle and chromosome configurations of human oocytes cryopreserved at the germinal vesicle and metaphase II stage.

BACKGROUND: Routine oocyte cryopreservation remains an elusive technique in the wide range of assisted reproductive technologies available. This study examines the effect of a cryopreservation protocol on the spindle and chromosome configurations of human oocytes cryopreserved at the germinal vesicle (GV) and metaphase II (MII) stage. METHODS: GV oocytes were randomly assigned to one of three groups: (i) control oocytes matured in vitro to MII stage (n = 156); (ii) oocytes cryopreserved at the GV stage and then matured in vitro (n = 90); (iii) oocytes cryopreserved at the MII stage (n = 147). Following cryopreservation and in-vitro maturation, immunostaining of tubulin and chromatin was performed, before visualization using confocal microscopy. RESULTS: A statistically significant increase was observed in the survival rate in group 2 (73.3%, 66/90) compared to group 3 (55.7%, 82/147) (P < 0.007). Exposure of oocytes to the cryoprotective solutions without freezing had no effect on the structure of their second meiotic spindle. However, statistically significant differences were observed on both spindle and chromosome configurations of oocytes from group 2 (5.2 and 5.2% respectively) and group 3 (16.2 and 18.8% respectively) compared with group 1 oocytes (71.6 and 82.0% respectively) (P < 0.001 in all cases). CONCLUSIONS: The protocol followed results in high rates of survival and potential for in-vitro maturation, but has a deleterious effect on the organization of the meiotic spindle of human oocytes cryopreserved at both the GV and MII stages.