Since the very early establishment of in vitro insemination, it became clear that one of the limiting steps is the achievement of fertilization. Among the different assisted fertilization methods, intracytoplasmic sperm injection emerged as the ultimate technique to allow fertilization with ejaculated, epididymal, and testicular spermatozoa. This work describes the early steps that brought forth the development of intracytoplasmic sperm injection and its role in assisted reproductive techniques. The current methods to select the preferential male gamete will be elucidated and the concerns related to the offspring of severe male factor couples will be discussed.
OBJECTIVE: To review the literature database regarding current methods for diagnosing male subfertility and to critique new testing methods that have the potential to be incorporated as part of routine semen analysis.
DESIGN: Literature database review.
SETTING: None.
PATIENT(S): None.
INTERVENTION(S): None.
MAIN OUTCOME MEASURE(S): None.
RESULT(S): Methods for performing high quality semen analysis are standardized and clearly presented in the 2010 World Health Organization (WHO) laboratory manual for the examination and processing of human semen. In spite of the fact that lower reference limits contained therein are now evidence-based, debate persists about their clinical value. One test put forth as being additive to the semen analysis is assessment of DNA integrity. However, due to lack of standardized methods and quality control measures, accessibility to instrumentation, and evidence-based reference values for clinical interpretation this test has not become incorporated into the clinical andrology mainstream. Novel tests that probe molecular function have emerged that also have promise for integration into routine clinical semen analysis.
CONCLUSION(S): Semen analysis, when performed according to WHO guidelines, will yield accurate and precise clinical laboratory data on traditional semen parameters. Due to the biological nature of the specimen in question definitive diagnosis of subfertility and its cause(s) remains enigmatic. Novel tests that may be easily standardized for subsequent multi-center, prospective randomized trials need to be integrated so more meaningful clinical diagnoses can be made.
OBJECTIVE: To review and summarize the current understanding of the epigenetic status of human sperm in regards to protamination, specific localization and modifications of retained histones, and DNA methylation.
DESIGN: Review of the relevant literature.
SETTING: University-based clinical and research laboratories.
PATIENT(S): Fertile and infertile men.
INTERVENTION(S): None.
MAIN OUTCOME MEASURE(S): Critical review of the literature.
RESULT(S): Sperm from normospermic, fertile men have epigenetic modifications consistent with gene “poising” at the promoters of genes involved in development, including the localization of retained histones with bivalent histone modifications and hypomethylation of DNA. These epigenetic marks are altered in some patients with abnormal spermatogenesis, and in some men who exhibit unexplained, altered embryogenesis during IVF therapy.
CONCLUSION(S): The sperm epigenome implies a poising of the paternal genome for embryogenesis and a possible role in the establishment of totipotency of the embryo and may help in understanding some causes of reduced fertility and transmission of disease risk.
OBJECTIVE: To provide a focused review of the scientific literature pertaining to spermatozoal RNA.
DESIGN: Review of the literature and appraisal of relevant articles.
SETTING: Not applicable.
PATIENT(S): Infertile male.
INTERVENTION(S): None.
MAIN OUTCOME MEASURE(S): Spermatozoal RNAs as potential epigenetic modifiers in early embryo development and as clinical markers of male infertility.
RESULT(S): The nucleus of mature spermatozoa contains a complex population of mRNAs and miRNAs despite its transcriptionally inert state.
CONCLUSION(S): A specific set of functional RNAs are delivered into oocytes during fertilization and are thought to contribute extragenomically to early embryonic development. Even if spermatozoal RNAs is merely residual, it still has the potential to greatly improve the investigative and diagnostic potential of male infertility.
INTERVENTION(S): Early secondary follicles were isolated from the ovaries and were cultured individually in vitro with or without androstenedione (10(-11) to 10(-5) M) for 12 days. Thereafter, the follicles were treated with hCG and epidermal growth factor (EGF).
MAIN OUTCOME MEASURE(S): Diameters and morphology of follicles and oocytes; E(2) and P secretion; and chromatin configuration and expression of growth differentiation factor 9 (GDF9) in oocytes were examined.
RESULT(S): Early secondary follicles developed to the preovulatory stage. Androstenedione treatments increased the follicle diameters, reduced survival rates of follicles, and promoted the formation of follicles with abnormal morphology, including misshapen oocyte. The secretion of E(2) and P was significantly higher in androstenedione-exposed follicles. Androstenedione prevented the alteration in chromatin configuration and reduced oocyte GDF9 expression. When follicles cultured with androstenedione were treated with hCG and EGF, the first polar body exclusion, chromosome alignment on metaphase plate, and spindle assembly were inhibited in the oocytes.
CONCLUSION(S): These results demonstrate that excess androgen induces abnormalities in the morphology and function of developing oocytes, which impairs oocyte meiotic competence.
Ovarian response to controlled ovarian hyperstimulation in cancer patients is diminished even before oncological treatment.
Fertil Steril. 2012 Jan 26;
Authors: Domingo J, Guillén V, Ayllón Y, Martínez M, Muñoz E, Pellicer A, Garcia-Velasco JA
Abstract
OBJECTIVE: To evaluate the results of controlled ovarian stimulation before chemotherapy for oocyte vitrification to preserve fertility in women diagnosed with cancer and compare them with a historical control group. DESIGN: A retrospective, multicenter, observational study performed between March 2007 and January 2011. SETTING: University-affiliated infertility clinics. PATIENT(S): Of 272 patients affected by cancer in our Fertility Preservation Program, 223 women underwent a stimulated cycle for oocyte vitrification according to our protocols before cancer treatment. Their results were compared with a historical control group of 98 patients diagnosed with male factor infertility who were stimulated for a conventional IVF cycle. INTERVENTION(S): Controlled ovarian stimulation and oocyte retrieval. MAIN OUTCOME MEASURE(S): Days of stimulation, total dose of gonadotropins, estrogen levels, and number of oocytes retrieved and vitrified. RESULT(S): No differences were found in days of stimulation, but significant differences in E(2) levels and the number of retrieved oocytes were measured, especially in the hormone-dependent cancer group. CONCLUSION(S): Patients with hormone-dependent cancer had a weaker response to controlled ovarian stimulation compared with patients with non-hormone-dependent cancer. Whether the oncological disease already affects the ovaries before chemo-/radiotherapy remains to be elucidated.
PMID: 22283969 [PubMed - as supplied by publisher]
Committee opinion: role of tubal surgery in the era of assisted reproductive technology.
Fertil Steril. 2012 Jan 27;
Authors:
Abstract
There is a need to determine the optimal treatment methods for patients with tubal factor infertility. This document reviews the available treatments and discusses factors that must be considered when deciding between surgical repair versus in vitro fertilization. This document replaces the 2008 document of the same name.
PMID: 22285747 [PubMed - as supplied by publisher]
FSH co-trigger after ovarian stimulation has been shown to improve oocyte competence and a recent report suggested that the FSH co-trigger can completely prevent OHSS. We report two cases of late OHSS after the FSH co-trigger was administered, underscoring the need for further research on the mechanisms, effects, benefits, and potential risks of FSH co-trigger.
PMID: 22285746 [PubMed - as supplied by publisher]
