Unraveling the link between genital infections, antibiotics, and preterm birth

There is an intricate relationship between genital infections, antibiotics, and preterm birth, according to a recent study published in Antibiotics.

Approximately 15 million infants are born preterm per year, indicating a significant health concern. Preterm birth is associated with increased risks of neonatal mortality and long-term morbidity.

Risk factors such as demographic, genetic, environmental, and infectious characteristics have been linked to preterm birth, with genital infections among pregnant women especially recognized as a gestation disrupting factor. Genital infections lead to inflammatory responses that can lead to preterm labor.

Genital infection management is difficult during pregnancy because of maternal and fetal safety concerns, as antibiotic use must combat the infection without adversely impacting maternal and fetal health. Additionally, data about mechanistic pathways and antibiotic efficacy in preventing preterm birth is lacking.

Investigators conducted a study to evaluate the association between genital infections, antibiotic use, and preterm birth. Participants included expectant mothers presenting with genital infections at the Obstetrics and Gynecology department of Clinical County Hospital, Timisoara, between 2019 and 2023.

Patients aged 18 years or older with available, comprehensive medical histories, agreement to data collection, positive bacterial cultures for genital infections during pregnancy, and antibiotic consumption history were eligible for inclusion. Exclusion criteria included HIV, pre-existing chronic conditions, incomplete or absent medical records, and pregnancy complications.

Exposures were extended to vaginal culture results, including microorganisms, antibiotic sensitivity, and multidrug resistance patterns. Various Gram-negative and Gram-positive bacterium types were analyzed.

Neonatal outcomes evaluated included gestational weight, age, and type of birth. Covariates included background maternal characteristics, lifestyle factors, and medical history variables.

There were 71 pregnant women with genital infections during pregnancy who had a preterm birth and 94 who gave birth at term included in the analysis. Participants with preterm birth were aged a mean 27.3 years, vs 28.1 years for women with full-term birth. Obesity was reported among 16.9% of the preterm birth group and 19.1% of the full-term group.

Of the preterm birth group, 18.3% reported smoking during pregnancy, 11.3% alcohol consumption during pregnancy, and 53.5% being primigravida. In the full-term group, these rates were 11.7%, 10.6%, and 57.4%, respectively.

A significantly greater proportion of preterm birth patients had sexually transmitted diseases vs full-term birth patients, at 25.4% and 3.2%, respectively. Genital herpes was reported in 8.5% and 1.1%, respectively. Significant differences were not observed for other conditions such as urinary tract infections and diabetes.

Fever and pelvis pain were also significantly more common in the preterm birth group, at 81.7% and 50.7%, respectively, vs 25.5% and 21.3%, respectively, in the full-term birth group. Vaginal spotting was reported in 40.8% vs 24.5%, respectively.

Gestational weight also differed significantly between the 2 groups. In the preterm birth group, 2.8% of infants at a gestational weight of 500 to 999 g and 8.5% a weight of 1000 to 1499 g. No infants were in these weight categories in the full-term group. A weight over 2500 g was reported in 67.8% of the preterm group vs 77.7% of the full-term group.

Significantly varying vaginal pH levels between the groups indicated the impact of genital infections. In the preterm group, the average pH was 5.5, vs 4.5 in the full-term group.

Nugent scores indicating normal flora were also lower in the preterm birth group, at 16.9% vs 41.5% in the full-term birth group. Bacterial vaginosis was reported in 33.8% vs 20.2%, respectively.

Resistance to Penicillin was reported in 42.3% of the preterm group and 19.1% of the full-term group. Resistance to second-generation Cephalosporin was reported in 29.6% and 12.8%, respectively, and resistance to third-generation Cephalosporin in 31% and 11.7%, respectively.

These results indicated an intricate association between genital infection, antibiotic use, and preterm birth risk. Investigators emphasized the importance of early detection, appropriate antibiotic use, and genital infection management.

Reference

Marti DT, Bratosin F, Rosca O, et al. Impact of genital infections and antibiotic use on incidence of preterm birth: A retrospective observational study. Antibiotics (Basel). 2024;13(3):240. doi:10.3390/antibiotics13030240