A pragmatic RCT of conventional versus increased concentration sucrose in freezing and thawing solutions for human embryos
Authors: Wood, M. J.; Mollison, J.; Harrild, K.; Ferguson, E.; McKay, T.; Srikantharajah, A.; Bell, L.; Bhattacharya, S.
Source: Human Reproduction, Volume 26, Number 8, 8 August 2011 , pp. 1987-1996(10)
Publisher: Oxford University Press
Abstract:BACKGROUNDIntact frozen-thawed embryos have a greater potential than damaged embryos to establish successful pregnancies. This study aimed to determine whether elevated concentrations of sucrose during freezing would increase the proportion of patients with ≥50% of embryos intact after thawing (primary outcome), and improve clinical outcome.METHODSIn a two arm, parallel group, pragmatic trial, IVF/ICSI couples were randomized prospectively to have their supernumerary embryos frozen in a medium containing 0.1 M sucrose (control; n = 99) or 0.3 M sucrose (intervention; n = 102).RESULTSMore control (74/99) than intervention (63/102) couples had at least one embryo thawed (P = 0.07). Significantly more (P = 0.005) intervention (53/63) than control (45/74) couples had ≥50% of embryos intact. Freezing in a medium containing 0.3 M sucrose increased by 3.4-fold [95% confidence interval (CI) (1.45, 7.82)] the likelihood of a couple having ≥50% of their embryos intact. In the fresh cycle, live birth rate per transfer was similar in the control (35/95) and intervention (36/93) groups (P = 0.91). More control (19/63) than intervention (9/59) couples had a live birth after frozen embryo transfer (P = 0.08). When fresh and frozen cycles were combined, fewer intervention (n = 102) than control (n = 99) couples had at least one live birth (42 versus 53%). The difference in cumulative live birth rate was not significant [hazard ratio = 0.75, 95% CI (0.49, 1.13); P = 0.17].CONCLUSIONSIncreasing the concentration of sucrose in the freezing medium improves embryo survival, but this is not reflected by increased cumulative birth rates.Clinical Trials Registration number: ISRCTN93314892.
Document Type: Research article
Publication date: 2011-08-08
- Human Reproduction features full-length, peer-reviewed papers reporting original research, clinical case histories, as well as opinions and debates on topical issues. Papers published cover the scientific and medical aspects of reproductive physiology and pathology, endocrinology, andrology, gonad function, gametogenesis, fertilization, embryo development, implantation, pregnancy, genetics, genetic diagnosis, oncology, infectious disease, surgery, contraception, infertility treatment, psychology, ethics and social issues. The highest scientific and editorial standard is maintained throughout the journal along with a rapid rate of publication.