Sugars Found in Breastmilk Could Prevent Premature Birth

Researchers from Vanderbilt University have discovered that sugars naturally found in breast milk can treat prenatal infections in human tissues and potentially prevent preterm births. The paper was published in the ACS Central Science.

Treating Group B streptococcus in pregnancy

Approximately 11.1% of babies are born prematurely worldwide every year, putting many mothers and infants in potentially life-threatening scenarios. There are several factors that can cause preterm birth, however 40% of cases are linked to infection. Group B streptococcus (GBS) is one of the most common bacteria that affect pregnancies. Infection during gestation can lead to many harmful effects such as neonatal pneumonia and preterm birth if left untreated.

Breastfeeding has been used and recommended for many generations to protect newborn babies during their first period of life. Breastmilk contains a concoction of ingredients that help keep babies safe from many diseases. One example includes the prebiotic molecules human milk oligosaccharides (HMOs) – sugars found in breast milk. Isolated HMOs have demonstrated antibacterial effects against GBS in cell culture previously and may offer protection to infants even before they’re born.

Existing treatments for GBS infection include antibiotics that could give rise to other potentially harmful bacteria strains. Antibiotic use during pregnancy may also lead to maternal gut dysbiosis, which has been associated with both harmful short-term and long-term effects on both mother and infant. Alternative treatments could prevent pregnancy complications without the undesired effects of unnecessary antibiotics.

HMOs provide a protective effect

Dr. Steven D. Townsend, Stevenson Professor of Chemistry at Vanderbilt College of Arts and Science, and colleagues sought to investigate HMO activity in GBS infections in pregnant mice and human tissues. The researchers infected human vaginal organoid tissue with GBS and treated the organoids with HMOs, discovering that these sugars prevented both bacterial adherence and biofilm formation, which can stop bacterial colonization, a “critical step in the enhancement of GBS disease”, the authors say.

Townsend and colleagues also demonstrated the beneficial effects of using HMOs during adverse pregnancy complications. Pregnant mice were inoculated with HMOs and infected with GBS the following day. The infected mice that were treated with HMOs experienced no instances of preterm premature rupture of the membranes, premature birth or maternal death compared to the controls, where a significant increase in these events was observed.

Townsend and team suggest these results are due to anti-inflammatory effects of HMOs that may cause a decrease in proinflammatory cytokines in response to infection and the downregulation of several genes linked to GBS virulence.

The future of natural therapeutics

As our understanding of the effects of maternal antibiotic exposure grows, the need for alternative treatments for GBS infection is becoming increasingly clear. The paper demonstrates HMOs' antimicrobial effect against GBS without the need for antibiotics. Townsend said, “These results highlight the potential of HMOs as promising therapeutic interventions in perinatal health.”

The research may pave the way for future work exploring how these sugars can be utilized as a viable option for the treatment of GBS and potentially other harmful infections.

Reference: Moore RE, Spicer SK, Lu J, et al. The utility of human milk oligosaccharides against Group B Streptococcus infections of reproductive tissues and cognate adverse pregnancy outcomes. ACS Central Science. 2023. doi: 10.1021/acscentsci.3c00101

This article is a rework of a press release issued by the American Chemical Society. Material has been edited for length and content.