Subzonal insemination, partial zona dissection or intracytoplasmic sperm injection? An easy decision?

This review aims to analyse and compare the results to date of subzonal insemination (SUZI), partial zona dissection (PZD) and intracytoplasmic sperm injection (ICSI) to evaluate critically whether it is now possible to replace SUZI and PZD by ICSI. It appears that ICSI is a much more efficient assisted reproduction technique than SUZI and PZD for resolving cases of severe male infertility and/or repeated failure of conventional in-vitro fertilization (IVF). For ICSI compared with SUZI and PZD, fertilization (49.4, 17.7 and 16.8% respectively), percentage of patients reaching embryo transfer (91.0, 55.1 and 23.3% respectively), percentage of transfers performed with two or three embryos (83.3% ICSI and 39.3% SUZI), pregnancy rate per embryo replacement (28.2, 18.7 and 16.5% respectively) and pregnancy rate per oocyte retrieval (24.8, 10.3 and 3.8% respectively) are all improved. In addition, cases of severely impaired semen characteristics, which were condemned to infertility for life with conventional IVF, SUZI or PZD, can now be treated and resolved efficiently with ICSI.