A pragmatic RCT of conventional versus increased concentration sucrose in freezing and thawing solutions for human embryos.
Hum Reprod
; 26(8): 1987-96, 2011 Aug.
Article
in En
| MEDLINE
| ID: mdl-21586432
ABSTRACT
BACKGROUND:
Intact 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.METHODS:
In 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).RESULTS:
More 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].CONCLUSIONS:
Increasing 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.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sucrose
/
Cryopreservation
/
Cryoprotective Agents
/
Embryo, Mammalian
/
Embryo Transfer
Type of study:
Clinical_trials
Limits:
Female
/
Humans
/
Pregnancy
Language:
En
Journal:
Hum Reprod
Journal subject:
MEDICINA REPRODUTIVA
Year:
2011
Document type:
Article
Affiliation country:
United kingdom