Clinical outcomes of vitrified-thawed embryo transfer using a pull and cut straw method

• Published in: Obstetrics & gynecology science Vol. 56; no. 3; pp. 182 - 189
• Main Authors: Lim, Joon Gyo, Heo, Young Tae, Min, Seung Gi, Min, Byeong Yeol, Uhm, Sang Jun, Kim, Nam Hyung
• Format: Journal Article
• Language: English
• Published: Korea (South) Korean Society of Obstetrics and Gynecology; Korean Society of Contraception and Reproductive Health; Korean Society of Gynecologic Endocrinology; Korean Society of Gynecologic Endoscopy and Minimal Invasive Surgery; Korean Society of Maternal Fetal Medicine; Korean Society of Ultrasound in Obstetrics and Gynecology 01-05-2013; 대한산부인과학회
• Subjects: Original; 산부인과학; Vitrified-thawed embryo; Pull and cut straw; Assisted hatching
• ISSN: 2287-8572; 2287-8580
• DOI: 10.5468/ogs.2013.56.3.182

To compare the clinical outcomes of patients with vitrified-thawed embryos transferred using either the 0.25 mL straw method and the pull and cut straw (PNC) method. To evaluate the clinical outcomes of patients with transferred embryos that underwent assisted hatching at the cleaved embryo (day 3) or the blastocyst (day 5) stage.
The study population consisted of women who underwent vitrified-warmed embryo transfer between May 2000 and December 2011 and assisted hatching was performed after warming of embryos. Cycles of thawing between assisted hatching treated and non treated groups were compared for survival and pregnancy rates.
The PNC vitrification method improved survival and pregnancy rates in partial lysed embryos. While assisted hatching did not affect the developmental and clinical pregnancy rates of the vitrified-warmed blastocyst group, it did increase the pregnancy rate of poor quality vitrified-warmed cleaved embryos.
These results suggest that PNC may increase the number of clinical pregnancies via the vitrification of both cleaved embryos and blastocysts. In addition, selective assisted hatching treatment of embryos that show a poor prognosis after warming may increase the rate of clinical pregnancy.