Repeated sperm injection under the zona following initial fertilization failure.
When fertilization fails following micromanipulative under-zona insemination, it is possible to repeat the procedure adding more spermatozoa to achieve fertilization, embryonic development and pregnancy. We report on 18 human in-vitro fertilization cycles where this approach was used. In nine cycles only late-fertilized embryos were available for transfer, and these gave rise to two viable pregnancies (22.2% per transfer). In six cycles, where a mixture of late- and timely fertilized embryos were available for transfer, two viable pregnancies arose (33.3% per transfer). In three cycles no fertilization was achieved even after reinsemination by repeated under-zona insemination.
Wiker
S R
SR
Reproductive Biology Associates, Atlanta, GA 30342.
Tucker
M J
MJ
Wright
G
G
Malter
H E
HE
Kort
H I
HI
Massey
J B
JB
D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008297:Male; D008845:Microinjections; D011247:Pregnancy; D013094:Spermatozoa / Q000502:physiology*; D015044:Zona Pellucida