Background: Poor ovarian response to standard in vitro fertilization-embryo transfer (IVF-ET) protocols or different regimens of treatment, as consequence of a diminished ovarian reserve, correlates strictly with patient age, elevated follicle-stimulating hormone (FSH) and reduced antral follicle count. The aim of the present pilot study was to evaluate the outcome of patients with poor prognostic features undergoing IVF-ET with natural cycles as a first approach and not as a consequence of a previous failure treatment.
Materials and methods: Eighteen aged patients (mean +/- standard deviation 40.2 +/- 0.7 years, range 37-43 years) with elevated serum FSH and reduced antral follicle count underwent intracytoplasmic sperm injection (ICSI) after spontaneous ovulation.
Results: A total of 26 natural cycles with ICSI were analyzed. Pregnancy was observed in three patients, of which two were ongoing as assessed by fetal heart beat at ultrasound scan performed 4-5 weeks after ET.
Conclusion: The overall pregnancy rates achieved (11.5% per cycle, 20.0% per ET) are comparable with those of conventional IVF-ET in aged patients, and not impaired by a single embryo transferred. Better embryo quality, as a consequence of natural selection of oocytes, better endometrium receptivity and monthly repeatability of the procedure, can balance the relatively low chance to perform ET.