Written by Susan Devaney Published on 22nd February 2022 Updated on 23rd May 2022

In previous years, many high profile women, including Chrissy Teigen, Michelle Obama and the Duchess of Sussex have openly discussed pregnancy loss. In recent days, singer Charlotte Church detailed the pain she experienced after suffering from a miscarriage. It’s still a topic shrouded in shame and unknowns. However, new research, published in BMC Medicine, has found that changes to a woman’s vaginal microbiome may be associated with miscarriage. 

Half of early miscarriages happen because of chromosome abnormalities in the baby, but the other 50% doctors don’t have an answer for. Researchers at the National Centre for Miscarriage Research – a partnership between University of Birmingham, University of Warwick and Imperial College London – have been making it their mission to find the answers. 

What’s the vaginal microbiome? 

According to Tommy’s, the vaginal microbiome is: “an environment of microorganisms which live inside the vagina. A healthy vaginal microbiome is mainly made up of a type of bacteria called lactobacillus. This helps maintain a healthy balance of microbes by preventing the growth of other potentially harmful bacteria.”

What did the experts find out?

Reacting off growing evidence, experts wanted to find out if the way a pregnant woman’s immune system interacts with the bacteria in her vagina can cause a miscarriage. The study, which involved recruiting 167 pregnant women from March 2014 to February 2019, looked at women who had had a miscarriage or experienced pain and/or bleeding during their first trimester of their pregnancy. Interestingly, women who had taken antibiotics, probiotics or progesterone supplements couldn’t be included as these might have changed their vaginal microbiome. 

The study found that, in total, 93 women had a miscarriage and 74 gave birth. Of the women who experienced a miscarriage, 54 had no chromosomal abnormalities in the embryo. As such, the researchers looked for molecular signs of inflammation and examined the vaginal bacteria present in all of the women. 

Looking to the future 

The good news is that researchers may have found a possible link between the two that may be treatable. However, more research is needed to be done to better understand what exactly triggers this immune response. The researchers are now actively looking for methods to analyse vaginal bacteria quickly in healthcare. 

“If confirmed by further research, this suggests that the vaginal microbiome might play a role in miscarriage,” said lead author Professor Phillip Bennett, from Imperial’s Department of Metabolism, Digestion and Reproduction. “If that is the case, this might highlight an important role for good vaginal hygiene in early pregnancy. For example, it might be a good idea to wash regularly, but to avoid perfumed soaps, gels and antiseptics as we know that these can affect the healthy balance of bacteria and acid levels in the vagina. It is best not to use vaginal douches because this can disrupt the normal vaginal bacteria.

“Our early findings don’t provide enough information for us to say that there’s a link between these kinds of products and miscarriage, but they do suggest we need to look more closely at the role of the vaginal microbiome.”