Can BV cause a miscarriage? This seems to be the million dollar question on many pregnancy forums. It is also still somewhat controversial in medical circles. Some doctors still advise their patients that BV does not cause miscarriages while others advise that BV does cause miscarriages. The official word on the subject is still in flux but what does the early research show? Does BV cause miscarriages according to the official evidence?
There are two significant research studies published in the British Medical Journal (BMJ) that conclude that BV is linked to a higher than normal rate of miscarriages. The first study was published in 1999 and followed women who were undergoing in vitro fertilization. All women in this study were tested extensively, including tests for BV. The bottom line conclusion was that women who tested positive for BV during their first trimester had a statistically higher chance of having a miscarriage. The second study was published in 2002 and involved 1214 women, i.e. it was a rather large study. This study showed a statistically higher chance of having a miscarriage in the second trimester if the woman had BV but not in the first trimester. Obviously, more large scale studies need to be done to prove convincingly beyond a shadow of a doubt if BV is associated with a higher frequency of miscarriages. However, these two research studies were peer reviewed and conducted by respected scientists and clinicians. There is no reason not to take the results seriously.
There also seems to be some debate over whether or not a BV infection causes miscarriages more in the first trimester or the second trimester. Some doctors seem to be telling their patients that BV is a more serious risk for late term (second trimester) miscarriages than in early (first trimester) miscarriages. However, it should be noted that it is sometimes very difficult to determine the cause of a first trimester miscarriage. In fact, some women have miscarriage during very early pregnancy without ever even knowing they were pregnant.
While the question of “can BV cause a miscarriage” cannot be answered with 100% certainty, it seems highly likely that this will be the ultimate conclusion of the traditional medical community. It is also the conclusion draw by many women who have had the experience. My heart goes out to these women and I have a great deal of respect for the fact that they are trying to get the word out on this very important, yet still controversial, subject.