Perhaps this article will help: http://www.wdxcyber.com/nvulva08.htm
Hello,
Recurrent vulvovaginal candidiasis is defined as four or more episodes of infection per year; it occurs in 5 to 8 percent of healthy women. Causes for recurrent infection are apparent in only a small group of women. These include women with poorly controlled diabetes and immunosuppressive therapy. In the remainder, causes for recurrent infection are not well understood and it is not clear it is related to sexual transmission and thus treating a patient's sexual partner is not advocated.
If the infections are not responding as well to Diflucan it may be that a different organism is the cause, or resistance has developed. A vaginal culture will be helpful in sorting that out.
Best regards,
Dr. Downing