Study links gut flora and fertility

Researchers are learning that the trillions of microbes making up the human microbiome are connected to an increasing number of biological processes and health conditions. Immune response, mental health, nutrition and vitamin uptake, and infectious disease outcomes are some of the biggies being discovered in the most current clinical research (Engineering. 2017;3[1]:71-82).

For the millions of women who hope to conceive a child but cannot, a recently published study adds fertility to that list and may shed some light on their situation by connecting gut microbiome composition and pregnancy outcomes.

Specifically, the preliminary study published last year in the Journal of Chemical Biochemistry Nutrition used metagenomic sequencing to examine genetic diversity in microbial communities found in 18 fertile women and 18 female patients with infertility (J Clin Biochem Nutr. 2020;67[1]:105-111). In short, the fertile group was found to have higher amounts of Bifidobacterium.

A second goal of the study was to examine the impact of prebiotic fiber on fertility, so researchers had 12 of the infertile women consume 10 g of prebiotic PHGG (partially hydrolyzed guar gum), as Sunfiber from Taiyo International, while attempting to conceive through in vitro fertilization. Sunfiber has been proven to nourish Bifidobacterium (Nutr Metab [Lond]. 2016;13:10).

Seven of the 12 infertile women were able to conceive—slightly higher than the known rate for patients subjected to assisted reproductive technology—leading researchers to tentatively conclude that “PHGG supplementation helped improve gut dysbiosis and the success of pregnancy in females with infertility.”

Admittedly, the sample size is quite small, and, “Further studies are needed to elucidate the mechanisms involved in this phenomenon, and a clinical study using a large number of samples is highly recommended,” according to the Japanese researchers leading the study.

But, it’s believed that the research is the first to reveal the differences in gut microbiota between fertile females and females with infertility, an important finding.

“It’s only been a few years since conversations began about the gut/brain connection, fueling interest in whatever else may be influenced by gut health. We’re not surprised that researchers are now associating the gut microbiome with fertility,” said Taiyo International Vice President Scott Smith, in a press statement promoting the recent study findings.

The U.S. infertility rate for women of childbearing age is 8.8%, and an estimated 12.7% of American women seek fertility assistance, according to the company.