Partial zona dissection of the human oocyte: a nontraumatic method using micromanipulation to assist zona pellucida penetration.
Partial zona dissection (PZD), a method using mechanical force to open the human zona pellucida, and zona drilling, which uses acidic Tyrode's (AT) medium, were compared in 1-day-old oocytes prior to reinsemination. The incidences of monospermy and polyspermy were 13/54 (24%) and 14/54 (26%) following PZD and 6/46 (13%) and 8/46 (17%) following the use of AT medium. This compared favorably with conventional reinsemination: 15/161 (9%) monospermy and 4/161 (3%) polyspermy. Three of the 27 PZD embryos became blastocysts, while none of the AT-exposed embryos developed satisfactorily. Eleven male-factor couples had some of their oocytes randomly treated with PZD prior to insemination; each of the patients had non-micromanipulated control oocytes. Monospermic fertilization and cleavage (23/34; 68%) doubled (P less than 0.05) when PZD was compared with the control oocytes (10/30; 33%). Replacing two PZD and a single control embryo in two patients resulted in twin pregnancies. A third twin pregnancy was established following replacement of only micromanipulated embryos.
Malter
H E
HE
Department of Gynecology and Obstetrics, Emory University, Atlanta, Georgia.
Cohen
J
J
D002455:Cell Division; D003470:Culture Media; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D007248:Infertility, Male / Q000628:therapy; D007317:Insemination, Artificial, Homologous; D008297:Male; D009865:Oocytes / Q000166:cytology; D010063:Ovum; D013084:Sperm-Ovum Interactions; D015044:Zona Pellucida
D003470:Culture Media