History of cervical excisional treatment is associated with changes in the cervical microbiota in women with preterm prelabor rupture of membranes.

Background: This study aimed to determine the differences in the cervical load and prevalence of Lactobacillus crispatus DNA, Lactobacillus iners DNA, Gardnerella vaginalis DNA, Sneathia sanguinegens DNA, and Ureaplasma species DNA between pregnant women with preterm prelabor rupture of membranes (PPROM) with and without a history of cervical excisional treatment. We also assessed the changes in the cervical load and prevalence of L. crispatus DNA, L. iners DNA, G. vaginalis DNA, S. sanguinegens DNA, and U. spp DNA. according to the cone length.

Methods: This retrospective study included 132 women with singleton pregnancies complicated by PPROM. For all women, information about the cervical loads of bacterial DNA corresponding to L. crispatus, L. iners, G. vaginalis, S. sanguinegens, and U. spp., which was assessed using PCR, was available.

Results: Women with a history of cervical excisional treatment had a higher cervical load of L. iners DNA (4.4 × 10⁶ copies DNA/mL vs. 3.5 × 10⁵ copies DNA/mL, p = .04) and a higher load and prevalence of U. spp. DNA (1.1 × 10⁵ copies DNA/mL vs. 9.6 × 10⁴ copies DNA/mL, p = .03; 2.7% vs. 0.5%, p = .04) than those without a history of cervical excisional treatment. In the subset of women with a history of cervical excisional treatment, those with a cone length 18 mm and more had a lower relative abundance of L. crispatus DNA (6% vs. 89%, p = .02), a higher load and relative abundance of L. iners DNA (1.1 × 10⁷ copies DNA/mL vs. 8.2 × 10⁵ copies DNA/mL, p = .04; 91% vs. 35%, p = .04), and higher loads of G. vaginalis DNA (7.6 × 10⁴ copies DNA/mL vs. 3.2 × 10² copies DNA/mL, p = .02) than those with cone length < 18 mm.

Conclusions: A history of cervical excisional treatment was associated with alterations in the cervical microbiota composition in pregnant women with PPROM.