What we learned from extended culture of 'rejected' day-3 cleavage stage embryos: a prospective cohort study

• Published in: Journal of ovarian research Vol. 10; no. 1; p. 35
• Main Authors: Hershko Klement, Anat, Ovadia, Michal, Wiser, Amir, Berkovitz, Arie, Shavit, Tal, Nemerovsky, Luba, Ghetler, Yehudith, Cohen, Ilan, Shulman, Adrian
• Format: Journal Article
• Language: English
• Published: England BioMed Central 16.05.2017; BMC
• Subjects: Adult; Blastocyst; Blastocyst - physiology; Cleavage Stage, Ovum - physiology; Cohort analysis; Cryopreservation; Embryo Culture Techniques; Embryo implantation; Embryo Implantation - physiology; Embryo transfer; Embryo Transfer - methods; Embryology; Embryos; Female; Health risk assessment; Humans; Implantation; Infertility; Laboratories; Maternal Age; Morphology; Pregnancy; Pregnancy Rate; Prognosis; Prospective Studies; Quality; Sperm; Embryo culture techniques; Embryo transfer; Embryo implantation; Blastocyst
• ISSN: 1757-2215; 1757-2215
• DOI: 10.1186/s13048-017-0332-5

To test whether poor quality day-3 embryos can undergo successful blastulation and implantation. A prospective cohort study was conducted. Whether or not a good quality embryo was transferred on day-3, poor quality (rejected) embryos were further cultured and followed. The clinical outcome of each embryo was assessed. A total of 694 rejected embryos (from 205 patients) were included, with a blastulation rate of 21.2% (147 embryos) compared to 64.2% general blastulation rate reported by our laboratory (P < 0.01). In a multivariate logistic regression model, only their grade on day-3 significantly affected blastulation (P = 0.01). A total of 97 embryos attained eligibility for fresh transfer or cryopreservation, only 6 of which resulted from a day-3 embryo scored < 2. Of these, 52 were transferred, resulting in 21 pregnancies (16 clinical and 5 chemical). In summary, 694 cultured embryos yielded 16 clinical pregnancies; a 2.3% clinical pregnancy rate. Low score day-3 embryos can result in successful blastulation and clinical pregnancies. However, the normal blastulation rate is poor.