RESUMEN
The present study aimed to correlate morphometric parameters of the oocytes with the occurrence of fertilization following intracytoplasmic sperm injection (ICSI). In a prospective, controlled cohort design, women (n = 32) who were candidates for ICSI had oocytes (n = 258) collected and submitted to morphometric evaluation using the Cronus3 software program. The morphometric parameters obtained were oocyte diameter, perivitelline space width, zona pellucida thickness, and first polar body diameter. The median oocyte diameter was similar in cases in which fertilization occurred compared with those in which fertilization failed (75.2 and 75.9 µm, respectively; P = .218). The 2 groups also had similar measurements of perivitelline space, zona pellucida, and first polar body. However, the best quality zygotes identified by a morphological score resulted from oocytes with larger diameter (75.6 vs 74.0 µm; P < .01) and narrow perivitelline space (5.3 vs 7.1 µm; P < .01). Embryo development, as assessed by cleavage at second day of culture, was not significantly associated with oocyte morphometric parameters. These findings suggest that morphometric parameters of the oocytes do not correlate with the occurrence of fertilization following ICSI but may assist in selecting oocytes more likely to originate high-quality zygotes.
Asunto(s)
Ectogénesis , Oocitos/citología , Inyecciones de Esperma Intracitoplasmáticas , Cigoto/citología , Adulto , Forma de la Célula , Tamaño de la Célula , Estudios de Cohortes , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Infertilidad/terapia , Masculino , Embarazo , Índice de Embarazo , Estudios Prospectivos , Adulto JovenRESUMEN
The aim of this study was to show the effects of freezing and thawing in bovine ovarian tissue by histological analysis. Ten cortical slices (2-4 mm in diameter) were obtained from each ovary by tru-cut biopsy and randomly divided into two groups: five fragments were immediately processed as a fresh tissue control group, while the remaining 5 fragments were slowly frozen using DMSO plus sucrose as cryoprotectors, then stored for two weeks and quickly thawed. Histological examination of all cryopreserved ovarian fragments showed no damage in the structure of the organ. Furthermore, there was no difference in the average number of primordial and primary follicles between the two groups of ovarian tissue. These data suggest that the bovine ovary can be used as a suitable model to test new freezing and thawing procedures in search for a standard protocol of human ovary cryopreservation.