it appears that there is either a persistent infection in the uterus or some deficiency of the immune system either local to the uterus or even generalised.
I assume that there has been some form or uterine irrigation. May be worth continuing either with a broad spectrum antibiotic or an Iodine solution.
Large volume flushes with dilute potassium permangenate or even warm saline are also worth trying.
Combining these treatments with repeated doses of prostaglandins at 10 -12 day intervals may also aid in clearing out residual infections.
Artificial insemination is likely to be cleaner than natural service.

15/9/11

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