A study published in The American Journal of Obstetrics and Gynecology reports that Mycoplasma genitalium (MGen) does not increase the risk of recurrent preterm birth. Researchers at UTHealth Houston, who followed nearly 500 pregnant individuals with prior complications, found that while the infection is common among those with history of preterm delivery, it does not act as a driver for subsequent early births.
Does MGen Cause Preterm Birth?
Current clinical data suggests that Mycoplasma genitalium does not directly trigger recurrent preterm birth. According to a prospective study led by Dr. Irene Stafford of UTHealth Houston, researchers tracked 500 pregnant individuals between July 2023 and December 2025 to determine the bacteria’s impact on pregnancy outcomes. While 12% of participants tested positive for the infection via FDA-cleared vaginal swabs, the presence of the bacteria did not correlate with an increased rate of spontaneous preterm delivery or second-trimester loss.
Why Does MGen Appear More Often in High-Risk Patients?
Although the infection does not cause recurrent preterm birth, it is statistically more prevalent in patients who have already experienced one. Dr. Stafford suggests that Mycoplasma genitalium may pose a higher risk during a first-time or “incident” infection. In these cases, the body has not yet developed an immune response, potentially leading to the inflammation that initially prompted researchers to investigate a link to pregnancy complications. This contrasts with earlier, limited research that hypothesized a broader, direct causal link between various Mycoplasma species and preterm labor.
Future Trends in Prenatal Screening
The medical community is shifting toward more targeted screening protocols as antimicrobial resistance grows. Because Mycoplasma genitalium is increasingly resistant to standard treatments, public health experts emphasize the importance of distinguishing between infections that require intervention and those that are incidental. According to Dr. Stafford, the UTHealth Houston findings provide clinicians with the clarity needed to avoid unnecessary alarm for patients who test positive but are not at an elevated risk of a second preterm birth.
Frequently Asked Questions
Is MGen considered a high-risk factor for every pregnant person?
No. While it is a common sexually transmitted infection linked to inflammation, the latest UTHealth Houston study indicates it does not increase the risk of recurrent preterm birth in individuals with a prior history of such complications.
Why is Mycoplasma genitalium hard to treat?
According to researchers, the bacteria lack a cell wall. This structural difference makes standard diagnostic tests less effective and complicates the selection of appropriate antibiotics, particularly as the bacteria develop resistance.
Should I be tested for MGen during pregnancy?
Clinical decisions regarding testing should be made in consultation with your OB-GYN. The recent findings suggest that for those at high risk of preterm birth, a positive result does not automatically equate to a higher likelihood of an early delivery.
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