Ultrasonically guided oocyte recovery for in vitro fertilization: an improved method.

Ultrasonically guided follicular aspiration is now routinely used for in vitro fertilization (IVF) in many centers. We present an improved method for oocyte recovery. One hundred nine consecutive patients with mechanical infertility submitted for IVF were included in the study. Superovulation was induced with human menopausal gonadotropin (hMG)/human chorionic gonadotropin (hCG). Oocyte recovery was ultrasonically guided, the bladder filled with phosphate-buffered saline (PBS), and a cannula with trocar used for single percutaneous puncture. The aspiration needle was of 1.6 mm in internal diameter. When compared to published data using smaller-bore needles, it seems that this improved needle increased the number of oocytes recovered to a mean of 6.5 and the number of embryos replaced to a mean of 3.9 per patient, with a pregnancy rate of 20% per transfer.