One simple change in how doctors prevent premature births could be a revolutionary lifesaver for pregnant women and newborn babies all over the world.
Expectant women with a record of early labor and who show signs that their cervixes are opening before they’re ready, undergo cervical cerclage – a procedure where the doctors sews the opening shut in an effort to postpone delivery then removes the stitches weeks later. The most common stitching method in the process uses braided sutures, reports Science Magazine.
A new study finds that cervical cerclages completed with these braided sutures are linked to three times the risk of stillbirths and close to twice the risk of preterm births.
Philip Bennett, study co-author and obstetrics researcher at Imperial College London, says that while there are no specific guidelines on what material to use in suturing, physicians prefer braided polyester sutures because they are thought to be stronger compared to thinner nylon monofilament sutures.
However, it turns out that the multiple fibers of braided sutures absorb fluids more, leading to bacteria growth that increases a pregnant woman’s risk for infections.
The researchers studied the medical records of 678 women who had undergone the stitching procedure to prevent preterm birth. Those who had used braided suturing material had a 15% risk of stillbirth, compared to 5% for those who used monofilament. The risk of preterm birth was 28% for the former, compared to 17% for the latter, as well.
To get to the bottom of the case, the research team monitored a smaller group of women during their pregnancies, randomly assigning 25 participants to get braided sutures and 24 to get stitches with monofilament. They then tracked the women’s vaginal environments throughout their pregnancies and found that the vaginal microbiome — naturally-occurring bacteria — had changed drastically in the women who got braided sutures.
Healthy pregnant women have microbiomes rich in Lactobacillus, which fights harmful bacteria using antibiotics and a strong acid. If Lactobacillus is disrupted in any way, invasive bacteria can begin to accumulate, causing inflammations in the cervix which in turn may lead to premature births. The study showed that 37% of the women who had braided sutures had increased bacterial activity in their vaginal environment compared to none of the women who had received monofilament sutures.
Some experts are skeptical about the study’s results, though. Andrew Shennan of King’s College London says there is a need for more studies on cervical stitching and vaginal microbiomes. He also takes issue with what he believes are rather “extraordinary” preterm and stillbirth numbers in Bennett’s research, which are much higher than the figures seen in prior studies on cerclage and braided sutures. He says there might be a rush to change suture materials without a deeper understanding of the risks and results.
Still, Bennett and his team are now looking into the composition of healthy vaginal microbiomes. They are hopeful that their findings could lead to therapies that could change the vaginal microbiome and cut down on birth complications in the future.
The study was published in the journal Science.