A tilting embryo culture system increases the number of high-grade human blastocysts with high implantation competence.
Human embryos normally experience mechanical stimuli during development in vivo. To apply appropriate stimuli to embryos, this study group developed a tilting embryo culture system (TECS) and investigated whether it could improve the grade of fresh human embryos compared with a control static culture system. A total of 450 retrieved oocytes from 32 IVF or intracytoplasmic sperm injection cycles of 32 women were cultured for 5-6 days. Oocytes were divided randomly into TECS and control groups and then were inseminated in vitro. All embryos were evaluated at days 3 and 5 using standard grading criteria for embryo quality. The rates of fertilization per mature oocyte and high-grade cleavage-stage embryo formation in the TECS group were similar to those in the control group. The rates of blastocyst formation and of blastocysts graded 3BB or higher at day 5 were significantly higher in the TECS group than those in the control group: 45.3% (67/148) versus 32.1% (51/159) (P=0.018) and 29.1% (43/148) versus 17.6% (28/159) (P=0.018), respectively. The TECS group produced more high-grade blastocysts than the control group. Embryo movement or mechanical stimulation during embryo culture may be beneficial for human embryonic development.
Division of Reproductive Medicine, Hiroshima Prefectural Hospital, 1-5-54 Ujinakanda, Minami-ku, Hiroshima, Japan. t-hara@hph.pref.hiroshima.jp
Tetsuaki
T
Hara
Koji
K
Matsuura
Takashi
T
Kodama
Keiko
K
Sato
Yuko
Y
Kikkawa
Tomomi
T
Muneto
Junko
J
Tanaka
Keiji
K
Naruse
D000328:Adult; D001755:Blastocyst / Q000502:physiology*; D015925:Cryopreservation; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D005260:Female; D005306:Fertilization; D006801:Humans; D054315:Oocyte Retrieval; D010812:Physical Stimulation; D011247:Pregnancy; D056826:Single Embryo Transfer