A randomized controlled trial of prophylactic antibiotics (co-amoxiclav) prior to embryo transfer.
BACKGROUND
Bacterial contamination of the transfer catheter during embryo transfer is associated with poor clinical outcomes. Antibiotics at the time of embryo transfer may improve outcomes. We evaluated the effect of co-amoxiclav on the rates of bacterial contamination of transfer catheters and clinical pregnancy.


METHODS
On the day of oocyte collection, 350 patients were randomized, with sequentially numbered opaque-sealed envelopes containing treatment allocation assigned randomly by computer, to receive co-amoxiclav on the day before and the day of embryo transfer, or no antibiotics. Following transfer, the catheter tips were cultured and assessed to identify the organism(s) isolated and to quantify the level of the contamination. Couples were followed for 8 weeks to determine whether they had achieved clinical pregnancy. Outcome assessors were blinded to the treatment allocation, and the analysis was by intention to treat.


RESULTS
Antibiotics significantly reduced catheter contamination rates (49.4 versus 62.3%, RR = 0.79, 95% CI: 0.64, 0.97, P = 0.03). There was no difference detected in clinical pregnancy rates between the two groups (36.0 versus 35.5%, P = 0.83) although there was a significant (P = 0.03) association between the level of bacterial contamination and clinical pregnancy rates.


CONCLUSIONS
Co-amoxiclav reduces catheter contamination, but this is not translated into better clinically relevant outcomes such as clinical pregnancy rates. Our findings do not support the routine use of antibiotics at embryo transfer.
Brook
N
N
Assisted Conception Unit, Guy's and St Thomas's Hospital Foundation Trust, London, UK.
Khalaf
Y
Y
Coomarasamy
A
A
Edgeworth
J
J
Braude
P
P
D000328:Adult; D019980:Amoxicillin-Potassium Clavulanate Combination / Q000627:therapeutic use*; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification; D002404:Catheterization; D004624:Embryo Transfer; D004866:Equipment Contamination; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000209:etiology; D008297:Male; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D011256:Pregnancy Outcome
D000900:Anti-Bacterial Agents; D019980:Amoxicillin-Potassium Clavulanate Combination