The role for preimplantation genetic diagnosis in balanced translocation carriers.

OBJECTIVE: Preimplantation genetic diagnosis is an established technique that provides an alternative to prenatal diagnosis for patients who are at risk of transmitting a serious genetic disorder to their offspring. Preimplantation genetic diagnosis has been used for couples who have been at risk for having offspring with single gene or X-linked disorders and for screening for common age-related aneuploidy and in couples who themselves carry balanced chromosomal rearrangements. The aim of this study was to summarize our experience using preimplantation genetic diagnosis after the identification of a parental balanced translocation, specifically as it relates to the number of embryos that are suitable for transfer after preimplantation genetic diagnosis for a known translocation and aneuploidy screening. STUDY DESIGN: This is a retrospective review of data from a single center that involved 6 couples that initiated the process of preimplantation genetic diagnosis for translocation and aneuploidy screening by fluorescent in situ hybridization. RESULTS: A total of 65 embryos were obtained, of which 56 embryos (86%) were suitable for fluorescent in situ hybridization analysis. After fluorescent in situ hybridization, 1 embryo was diagnosed as normal or balanced (1.7%). Forty-three embryos (76.8%) were unbalanced for the translocation; 8 embryos (14.3%) were aneuploid, and 4 embryos (7.1%) were uninformative. There were no clinical pregnancies. CONCLUSION: In our experience, there are very few embryos that are available for transfer from these patients after translocation and aneuploidy screening because of multiple unbalanced segregation products and a high rate of aneuploidy. Factors that contributed to this may be related to which parent carries the translocation, methods that were used for in vitro fertilization, and advanced maternal age. Although preimplantation genetic diagnosis for translocation carriers theoretically can enhance the pregnancy rate for a couple, there are limitations. This information should be shared with couples who are contemplating preimplantation genetic diagnosis for translocation, and the options of sperm or egg donor should be considered.

Follicular development, ovulation, and corpus luteum formation in cryopreserved human ovarian tissue after xenotransplantation.

OBJECTIVE: To assess the competency of human frozen/thawed ovarian follicles matured in xenografts to form functioning corpora luteae after human chorionic gonadotropin (hCG) administration. DESIGN: Prospective controlled animal study. SETTING: University research laboratory. PATIENT(S): Three women (19, 28, and 36 years) who underwent oophorectomy. ANIMAL(S): Nineteen female severe combined immunodeficient (SCID) mice. INTERVENTION(S): Cryopreserved human ovarian tissues were grafted into the s.c. space of bilaterally oophorectomized SCID mice. All the animals were stimulated with pregnant mare's serum gonadotropin (PMSG) for 4 weeks starting from 16 weeks after transplantation. Twelve animals were injected with hCG at the end of gonadotropin stimulation. MAIN OUTCOME MEASURE(S): [1] The rate of grafts with growing follicles, with antral follicles, and/or with corpora luteae. [2] The histologic assessment of follicles and corpora luteae. [3] The serum progesterone and estradiol level in animals with corpus luteum in the grafts. RESULT(S): [1] The rate of grafts with growing follicles and with corpora luteae was 33% to 100%, and 28% to 50%, respectively. [2] Corpora luteae in xenografts were all morphologically normal. [3] The progesterone levels were all above 3.0 ng/mL. CONCLUSION(S): This study showed that the cryopreserved human ovarian follicles can be matured to a stage at which they can form functioning corpora luteae in the host animal.