Human embryo fragmentation in vitro and its implications for pregnancy and implantation.
OBJECTIVE
To evaluate the effects of fragmentation and fragment removal in day 3 human embryos on implantation and pregnancy.


METHODS
Retrospective analysis of ETs homogeneous with respect to embryo fragmentation.


METHODS
A program of IVF-ET.


METHODS
The study population consisted of 2,410 patients.


METHODS
The degree and pattern of fragmentation were evaluated on days 2 and 3; microsurgical fragment removal was performed after assisted hatching on day 3.


METHODS
Clinical pregnancy and implantation rates.


RESULTS
The degree and pattern of fragmentation significantly impact pregnancy and implantation. With the application of microsurgical fragment removal before ET, embryos with 6%-35% fragmentation implant with similar frequency. The presence of large fragments (type IV) is detrimental to the developing embryo, whereas localized or small and scattered fragments do not significantly affect implantation.


CONCLUSIONS
The potential of fragmented embryos for implantation is determined partly by the distribution of fragments. Adoption of an embryo classification system reflecting types of fragmentation is advisable. The use of microsurgical fragment removal significantly alters the course of development for some embryos and improves their implanting potential.
Alikani
M
M
Institute for Reproductive Medicine and Science of Saint Barnabas, West Orange, New Jersey, USA. mina.alikani@embryos.net
Cohen
J
J
Tomkin
G
G
Garrisi
G J
GJ
Mack
C
C
Scott
R T
RT
D000328:Adult; D053938:DNA Fragmentation; D010064:Embryo Implantation; D004622:Embryo, Mammalian; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies