Ultrastructure of cytoplasmic fragments in human cleavage stage embryos.
OBJECTIVE
The goal of this study was to evaluate the ultrastructure of cytoplasmic fragments along with the effect of cytoplasmic fragment and perivitelline space coarse granulation removal (cosmetic microsurgery) from embryos before embryo transfer on ART outcomes.


METHODS
One hundred and fifty intracytoplasmic sperm injection cycles with male factor infertility were included in this prospective study. Patients were divided into three groups of case (n = 50), sham (n = 50), and control (n = 50). Embryos with 10-50 % fragmentation were included in this study. Cosmetic microsurgery and zona assisted hatching were only performed in case and sham groups respectively. Extracted fragments were evaluated ultrastructurally by transmission electron microscopy (TEM). Rates of clinical pregnancy, live birth, miscarriage, multiple pregnancies, and congenital anomaly in the three groups were also compared.


RESULTS
Micrographs from TEM showed that mitochondria were the most abundant structures found in the fragments along with mitochondria-vesicle complexes, Golgi apparatus, primary lysosomes, and vacuoles. There were no significant differences in demographic characteristics, laboratory and clinical data, or embryo morphological features between the groups. The rate of clinical pregnancy in control, sham, and case groups had no significant differences (24, 18, and 18 %, respectively). The rates of live birth, miscarriage, multiple pregnancy, and congenital anomaly were also similar between the different groups.


CONCLUSIONS
Our data demonstrated that cosmetic microsurgery on preimplantation embryos had no beneficial effect on ART outcomes in unselected groups of patients. As mitochondria are the most abundant organelles found in cytoplasmic fragments, fragment removal should be performed with more caution in embryos with moderate fragmentation.
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Iman
I
Halvaei
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran. khalili59@hotmail.com.
Mohammad Ali
MA
Khalili
Division of Reproductive Endocrinology and Infertility, Department of Ob-Gyn, Geisel School of Medicine at Dartmouth, Lebanon, NH, USA.
Navid
N
Esfandiari
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Somayyeh
S
Safari
Research and Clinical Center for Infertility, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Ali Reza
AR
Talebi
Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, La Sapienza University of Rome, Rome, Italy.
Selenia
S
Miglietta
Department of Anatomy, Histology, Forensic Medicine and Orthopaedics, La Sapienza University of Rome, Rome, Italy.
Stefania A
SA
Nottola
D000022:Abortion, Spontaneous; D000328:Adult; D001755:Blastocyst / Q000648:ultrastructure*; D002970:Cleavage Stage, Ovum; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D008247:Lysosomes / Q000648:ultrastructure; D008297:Male; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000648:ultrastructure*; D011247:Pregnancy; D011256:Pregnancy Outcome; D027724:Reproductive Techniques, Assisted; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods
Cosmetic microsurgery; Embryo fragmentation; Mitochondria; Transmission electron microscopy