Gonadotropin Type in Ovarian Stimulation

The follicular environment is primarily influenced by the type of gonadotropin the follicle is exposed to during the follicular phase. The role of gonadotropins has been especially important in improving the efficiency of in vitro fertilization. Several studies comparing the use of human menopausal gonadotropin (hMG) with recombinant follicle-stimulating hormone (rFSH) have found significant differences in the endocrinological profile and the follicular dynamics. These differences have been related to the human chorionic gonadotropin (hCG)-driven luteinizing hormone (LH) activity added to hMG. Moreover, differences in the proportion of acid residues in FSH molecules should be considered.

On the other hand, the main physiological regulatory hormones of follicular survival are the gonadotropins. Suppression of serum gonadotropins leads to massive apoptosis of granulosa cells in developing follicles resulting in atresia; whereas, gonadotropin treatment of early antral and pre-ovulatory follicles prevents this unplanned apoptosis. However, studies using cultured rat granulosa cells have shown that treatments with FSH or LH/hCG are ineffective in preventing spontaneous apoptosis, suggesting neighboring theca cells and local factors produced in the ovary are important for regulation of follicle growth and atresia.

Inclusion criteria

• 18-35 years old
• regular menstrual cycles
• no hereditary or chromosomal diseases normal karyotype negative for sexually transmitted diseases
• at least seven antral follicles per ovary

Exclusion criteria

• PCO