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Giovanni Coticchio

Publications and source records attributed to Giovanni Coticchio.

8 recordsLinked to original sources
PubMed2006

Cumulative pregnancy rates resulting from the use of fresh and frozen oocytes: 7 years' experience.

Storing supernumerary embryos and transferring them later fully utilizes the reproductive potential of retrieved oocytes, allowing a significant increase in the overall number of pregnancies achieved from a single cycle of ovarian stimulation treatment. As an alternative to embryo cryopreservation, preservation of unfertilized oocytes has been proposed to maximize clinical outcome. This paper presents data concerning the cumulative pregnancy rate after use of fresh and cryopreserved oocytes. In 80 treatment cycles in which patients chose to have only a few fresh oocytes inseminated, 24 pregnancies were obtained (30.0%), with an implantation rate of 22.6%. After cryopreservation with the standard slow-cooling protocol, the survival, fertilization and cleavage rates of 918 frozen oocytes were 43.4, 51.5 and 86.0% respectively. A total of 14 frozen pregnancies were achieved, with pregnancy rate 19.2% per transfer and implantation rate 12.3%. The cumulative pregnancy rate was 47.5% per patient. Therefore, despite a low rate of oocyte post-thaw survival, it appears that oocyte storage appreciably improves the number of pregnancies per treatment cycle in cases in which only a minority of oocytes are destined for the fresh treatment. This outcome provides valuable information for appraising the chances of clinical success when the option of embryo cryopreservation is not available.

Adult↗
PubMed2005

Polar body morphology and spindle imaging as predictors of oocyte quality.

It has been suggested that first polar body (PBI) morphology reflects oocyte competence. Oocytes with an intact normal-sized PBI have been described as generating better day 2 embryos, higher blastocyst yield, and increased pregnancy and implantation rates. In other studies, PBI morphology was found to be unrelated to fertilization rate, embryo quality, and blastocyst formation. In a prospective analysis, the predictive value of the PBI was investigated by comparing the development of oocytes retrieved from intracytoplasmic sperm injection patients and displaying different PBI morphology, classified according to the following characteristics: normal size and smooth surface (I), fragmented (II), rough surface (III), or large size (IV). Fertilization rates were 59, 57, 64 and 60% respectively. No significant differences were found between the various groups. The proportions of high quality (grade A) day 2 embryos were also comparable among groups I-III (14, 12 and 17% respectively), while the low number of grade A embryos in group IV (two embryos) did not allow comparison with the other classes. These data do not suggest that PBI selection can contribute to identification of embryos with high developmental ability. In order to establish alternative criteria for oocyte selection, a metaphase II (MII) spindle analysis was also conducted via Polscope. In oocytes of patients of different age, spindle retardance (which reflects the high order and density of microtubules) was compared with parameters of embryo development. In aged patients, a trend was observed between low retardance and poor embryo quality, although in general the association between retardance and oocyte developmental performance did not reach statistical significance.

Adult↗
PubMed2005

Predictive factors for embryo implantation potential.

In spite of recent improvements in IVF, pregnancy rates have not increased significantly and one of the major problems remains the high multiple pregnancy rate. Better criteria are therefore necessary to establish the viability of a transferable embryo. Early prognosis of the developmental fate of the oocyte would help in selecting the best embryos to transfer, but non-invasive selection at the oocyte stage (extracytoplasmic and intracytoplasmic morphology) has proved to be of little prognostic value. Recently, it has been shown that follicular vascularization appears to be predictive of oocyte developmental fate, making it a good first-step approach for selection. Observation of pronuclei patterns at the zygote stage appears to offer an additional prognostic tool, correlating well with IVF outcome. Morphological evaluation of the embryo at 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 best embryos with reduced risk of aneuploidies, though not all major chromosomal aberrations are excluded by prolonged in-vitro culture. In summary, selecting the best embryo for transfer is a decision that should be based on choices made during the different stages of assisted reproductive technologies.

Blastocyst↗
PubMed2004

Influence of thyroid hormone on mouse preantral follicle development in vitro.

OBJECTIVE: To evaluate the role of 3,3',5-triiodothyronine (T(3)) on ovarian follicle development in vitro. DESIGN: Experimental study. SETTING: University reproductive biology unit. ANIMAL(S): CD1 mice (female). INTERVENTION(S): In vitro culture. MAIN OUTCOME MEASURE(S): Assessment of follicle and oocyte development following a 6-day culture with FSH (100 mU/mL), (Bu)(2)cAMP (0.5 mM), and T(3) (1-100 nM), alone or in combination. RESULT(S): A high percentage of in vitro grown (IVG) FSH-stimulated follicles formed an antral cavity (AC), while the addition of T(3) (100 nM) significantly reduced this response in a statistically significant manner. A statistically significant recovery of AC formation was obtained by limiting exposure to 4 days of culture. Formation of AC was induced by (Bu)(2)cAMP, which prevented T(3)-mediated suppression of AC formation. Under different conditions, high proportions of germinal vesicle-arrested IVG oocytes displayed condensed chromatin configuration. The capacity to undergo germinal vesicle breakdown (GVBD) was similar in all groups, and a statistically significant reduction in the percentage of oocytes with PB1 was recorded when T(3) was added to FSH or (Bu)(2)cAMP. This ability was partially recovered by removing T(3) on day 4 of culture. CONCLUSION(S): Exposure to high T(3) concentrations can impair preantral follicle development, but this effect can be partly reverted by restoring a physiological hormonal milieu before follicle commitment to antral development.

Animals↗
PubMed2004

Pregnancies and births after oocyte cryopreservation.

OBJECTIVE: To determine the potential of oocyte cryopreservation techniques. DESIGN: Retrospective data analysis. SETTING: A tertiary infertility center. PATIENT(S): Sixty-eight patients (29 to 37 years of age) undergoing assisted reproduction procedures for infertility problems. INTERVENTION(S): Oocytes from women treated for infertility were cryopreserved with a slow cooling/rapid thawing protocol in which 1,2 propanediol and sucrose were used as cryoprotectants. Eighty-six thawing cycles were performed. MAIN OUTCOME MEASURE(S): Rates of survival after thawing, fertilization after intracytoplasmic sperm injection, cleavage, implantation, and pregnancy. RESULT(S): We treated 68 patients through 86 thawing cycles. Seven hundred thirty-seven oocytes were thawed, and 59 transfer cycles were performed. The survival rate was 37%. The fertilization and cleavage rates were 45.4% and 86.3%, respectively. A total of 15 clinical pregnancies were achieved with pregnancy rates of 25.4% per transfer and 22% per patient. There were three miscarriages, resulting in an abortion rate of 20%. Seventeen of the 104 transferred embryos implanted, corresponding to an implantation rate of 16.4%. Thirteen babies were born, 8 females and 5 males. CONCLUSION(S): Statistically significant results were obtained for fertilization, cleavage, and pregnancy rates. Our results show oocyte cryopreservation may represent an alternative to embryo storage in selected cases.

Cell Survival↗
PubMed2004

What criteria for the definition of oocyte quality?

Although the spermatozoon provides an essential contribution to the generation of a new individual, the developmental fate of the embryo is principally dictated by the oocyte. Oocyte competencies are acquired throughout oogenesis, via the interaction with somatic cells. The ability to reinitiate the meiotic process and undergo preimplantation development is progressively determined during the antral phase. It is known that these changes involve the nuclear and cytoplasmic compartments, respectively, but the underlying cellular and molecular mechanisms are still poorly understood. Analysis of various aspects of oocyte morphology (cytoplasm, zona pellucida, and polar body) via conventional phase-contrast microscopy has generated contrasting evidence on the possibility of establishing reliable criteria for the prediction of developmental potential. The introduction of a newly developed microscopy technique based on the detection of polarized light generated by birefringent cell structures has offered the possibility of visualizing noninvasively the meiotic spindle, whose presence is critical for fertilization and later developmental stages. However, further studies are needed to standardize and interpret the information accessible through such a technique. Although unable to preserve cell viability and therefore provide a method by which to select oocytes with superior developmental competence, invasive techniques can make a fundamental contribution to defining objective criteria of oocyte quality. In particular, immunofluorescence analysis, which is able to identify critical anomalies of the meiotic spindle and cytoskeleton organization that can account for oocyte quality, is an important method for assessing the efficiency of in vitro maturation systems.

Female↗
PubMed2004

Artificial reproductive technology achievements for optimizing embryo quality.

Evaluation of morphological characteristics, to date, has been the most widely accepted method for the selection of embryos with higher developmental ability and optimization of the outcome of in vitro fertilization (IVF). Improvement in clinical results has also been pursued through attempts to generate embryos of high quality or to identify more reliable selection criteria. This work evaluates the possibility of improving embryo quality and subsequent IVF outcome in situations in which creation of supernumerary embryos is not allowed. Optimization of gamete selection and conditions of insemination, such as hormonal therapy to improve sperm quality of patients undergoing intracytoplasmic sperm injection treatment, use of power Doppler image for follicle selection, short coincubation of gametes during insemination, and use of a polscope for spindle detection, is described.

Blastocyst↗