+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Blastocyst formation and hatching in vitro following zona drilling of mouse and human embryos



Blastocyst formation and hatching in vitro following zona drilling of mouse and human embryos



Gamete Research 24(1): 67-80



Hatching in vitro was studied following zona drilling of 507 two-cell mouse embryos using three methods: 1) acidic Tyrode's (AT), 2) partial zona dissection (PZD) using a sharp microneedle, and 3) zona chiseling (CH), using a large beveled needle. PZD and CH were performed while the embryos were kept in a sucrose/PBS solution. Hatching was compared to 191 unmicromanipulated controls. The incidences of cavitation and completion of hatching did not differ between groups, however more micromanipulated embryos (20-25%) hatched partially than controls (9%). The zona pellucida thinned in 59/59 (100%) control blastocysts during expansion, but in only 3/205 (2%) micromanipulated blastocysts. The hatching gap was wide in all control embryos, but smaller in 96/129 (75%) micromanipulated embryos. Partially hatched blastocysts with a "figure-8" shape were found in 59/129 (46%) micromanipulated embryos and in none of the 39 hatching controls. Hatching usually occurred a day earlier in micromanipulated embryos as 214/218 (98%) had started extruding on day 5 as compared to 20/59 (27%) control blastocysts. Fifty percent of 1-day-old human oocytes were fertilized following PZD and reinsemination and 15/31 (48%) were monospermic. Thirteen monospermic embryos cleaved, six compacted and four cavitated--of these, three extruded through the PZD incision upon expansion. The zonae did not thin and one blastocyst twinned spontaneously as it was caught between the thick ridges of the PZD hole. Results indicate that the hatching process is abnormal following zona drilling; more embryos start hatching, extrusion occurs earlier, and many become trapped which may lead to artificial twinning or the formation of trophoblastic vesicles.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 007064439

Download citation: RISBibTeXText

PMID: 2591852

DOI: 10.1002/mrd.1120240110


Related references

Enriched fractions containing an estrogen -dependent sheep oviduct glycoprotein prevent in vitro hardening of the zona pellucida and enhance in vitro blastocyst formation and hatching in the mouse. Biology of Reproduction 52(SUPPL 1): 153, 1995

Effects of laser drilling on blastocyst hatching and pregnancy rates from in vitro produced cattle embryos. Theriogenology 55(1): 352, January 1, 2001

Assisted hatching by zona drilling of human embryos in women of advanced age. Human Reproduction 12(2): 317-320, 1997

Partial dissection of the zona pellucida of frozen-thawed e human embryos may enhance blastocyst hatching, implantation, and pregnancy rates. American Journal of Obstetrics and Gynecology 165(2): 341-345, 1991

Partial dissection of the zona pellucida of frozen-thawed human embryos may enhance blastocyst hatching, implantation, and pregnancy rates. American Journal of Obstetrics and Gynecology 165(2): 341-4; Discussion 344-5, 1991

Implantation enhancement by selective assisted hatching using zona drilling of human embryos with poor prognosis. Human Reproduction 7(5): 685-691, 1992

Effects of removal of necrotic blastomeres from mouse cryopreserved embryos on blastocyst formation and hatching. Theriogenology 64(5): 1114-1120, 2005

Improvement in blastocyst hatching of mouse embryos cocultured with human placental cells. Journal Of Assisted Reproduction & Genetics. 10(7): 463-467, 1993

Effect of assisted hatching by partial zona pellucida dissection on mouse embryos in vitro. Journal of the Formosan Medical Association 94(8): 463-468, 1995

A new mouse model for embryos with a hatching deficiency and its use to elucidate the mechanism of blastocyst hatching. Fertility and Sterility 59(6): 1296-1301, 1993

Visualization of atypical hatching of a human blastocyst in vitro forming two identical embryos. Fertility and Sterility 80(6): 1502-1503, 2003

A prospective, randomized study to compare acidified Tyrodes zona drilling with laser-assisted hatching for day-3 embryo biopsy followed by blastocyst culture. Fertility & Sterility 80(Suppl 3): S197-S198, 2003

Effect of L-carnitine on in vitro developmental rate, the zona pellucida and hatching of blastocysts and their cell numbers in mouse embryos. International Journal of Reproductive Biomedicine 14(10): 649-656, 2016

The use of Matrigel at low concentration enhances in vitro blastocyst formation and hatching in a mouse embryo model. Fertility & Sterility 71(6): 1133-1137, 1999

Trypsin-like hatching enzyme of mouse blastocysts: Evidence for its participation in hatching process before zona shedding of embryos. Development Growth & Differentiation 36(2): 149-154, 1994