In vitro fertilization-intracytoplasmic sperm injection split: an insemination method to prevent fertilization failure.
OBJECTIVE
To determine whether the performance of intracytoplasmic sperm injection (ICSI) in cases of unexplained infertility and of borderline semen parameters can prevent fertilization failure.


METHODS
Prospective cohort study.


METHODS
Hospital-based assisted reproductive technology program.


METHODS
Sixty couples with unexplained infertility (group 1) and 50 couples with borderline semen (group 2).


METHODS
Conventional IVF and ICSI were performed on sibling oocyte cumulus complexes.


METHODS
Rate of fertilization according to patient diagnosis.


RESULTS
The fertilization rate per oocyte cumulus complex in couples with unexplained infertility (group 1) was significantly higher with ICSI (65.3%) compared with IVF insemination (48.1%). Fertilization rates per OCC in couples with borderline semen (group 2) were not significantly different between ICSI (58.1%) and IVF (56.7%). In group 1, failure of fertilization after IVF insemination occurred in 10 of the 60 couples (16.7%) and in none with ICSI. In group 2, 2 of 50 couples (4.0%) failed fertilization by IVF, and 1 (2.0%) failed with ICSI. No couple in group 2 failed both IVF insemination and ICSI.


CONCLUSIONS
In couples with unexplained infertility, a higher fertilization rate was achieved through ICSI compared with conventional IVF. No such benefit could be demonstrated for couples with borderline semen parameters. The use of ICSI rescued 12 of 110 cycles (10.9%) where IVF failed. Adoption of the ICSI-IVF insemination split in cases of unexplained infertility may help eliminate fertilization failures.
Hershlag
Avner
A
Center for Human Reproduction, Ambulatory Surgery, North Shore University Hospital-New York University School of Medicine, 300 Community Drive, Manhasset, NY 11030, USA. ahershlag@nshs.org
Paine
Terry
T
Kvapil
Georgina
G
Feng
Huailiang
H
Napolitano
Barbara
B
D015331:Cohort Studies; D005260:Female; D005306:Fertilization / Q000502:physiology*; D006801:Humans; D007248:Infertility, Male / Q000628:therapy*; D008297:Male; D009865:Oocytes / Q000502:physiology; D011247:Pregnancy; D011446:Prospective Studies; D012661:Semen / Q000502:physiology*; D013076:Sperm Count; D020554:Sperm Injections, Intracytoplasmic; D013081:Sperm Motility / Q000502:physiology