[Spermatogenesis arrest]. / Detención de la espermatogénesis.

Spermatogenesis arrest is a complex process of interruption in the differentiation of germinal cells of specific cellular type, which elicits an altered spermatozoa formation. In contrast, hypospermatogenesis is defined as a decrease in number of germ cells and its proportion. Factors identified intervening upon spermatogenesis arrest are: genetic, hormonal, growth factors, interaction between Sertoli and germ cells and ectoplasmic specialization integrity of spermatozoa. In addition, environmental toxic effects have shown to exert subletal and letal cellular damage with gene disruption. Hence in this work we review sperm physiology along with etiologic elements associated to spermatogenesis arrest delineating the most appropriate conduct for diagnosis and treatment.

[Epidemiological analysis of infertility in a Mexican population]. / Análisis epidemiológico de la infertilidad en una población mexicana.

BACKGROUND: Infertility is defined as the failure to conceive after a year of sexual life without a method of birth control. Most studies indicate that 15% of all couples will experience primary or secondary infertility in some moment of their reproductive life. OBJECTIVE: To gain knowledge of general characteristics from patients with infertility in our environment (social, clinical, diagnostic and therapeutic) that attended the Reproductive Biology Department of Hospital Juárez de Mexico. PATIENTS AND METHODS: A descriptive, observational, situational, and retrospective indagatory study was performed on 116 infertile patients, seen in the outpatient clinic, from January through December 1999. All had entered our protocol of infertility and selected treatment. RESULTS: The altered ovarian endocrine factor was the most frequent (82.7%), followed by cervical factor (80%), masculine factor (38%) and tuboperitoneal factor (29%). In most cases the cause was multifactorial. The percentage of successful pregnancies (31.88%) was similar to that reported in the literature. CONCLUSIONS: The most common factors that influence infertility resembled those exhibited by specialized clinics of affluent countries with similar pregnancy rates.