Hl. Chen et al., FAILED FERTILIZATION IN-VITRO - 2ND-DAY MICROMANIPULATION OF OOCYTES VERSUS REINSEMINATION, Fertility and sterility, 63(6), 1995, pp. 1337-1340
Objective: To compare routine reinsemination with 2nd day micromanipul
ation in patients with poor day 1 fertilization. Design: A retrospecti
ve review of patient records. Setting: The Mount Sinai Medical Center
Assisted Reproductive Technologies Program. Participants: Patients und
ergoing IVF-ET who had poor fertilization (<35%) with standard insemin
ation and underwent second day reinsemination of oocytes (group I, n =
84) compared with patients who underwent 2nd day micromanipulation wi
th subzonal insemination (group II, n = 12). Main Outcome Measures: Fe
rtilization rate, cleavage rate, number of embryo transfers, and pregn
ancy rate. Results: Fertilization rate and cleavage rate were signific
antly higher in group II patients. Pregnancies per transfer were simil
ar between groups I (3/21, 14.3%) and II (0/9, 0%). Second day fertili
zation was possible in 9 of 12 group II patients, and fertilization ra
te was higher than day 1 in all nine, however, only 50% achieved cleav
age, and none achieved pregnancy. Conclusions: Although micromanipulat
ing oocytes that fail to fertilize may identify occult male factor inf
ertility, may help the clinician plan future cycles, and may result in
fertilization and even transfer of embryos in some cycles, there were
no pregnancies in our series, and, for now, the clinical efficacy of
this procedure remains in question.