Cervical excision treatment increases intraamniotic infection risk

According to a recent study published in the American Journal of Obstetrics & Gynecology, the risk of intraamniotic infection is greater in women with a history of cervical excisional treatment.

Preterm prelabor rupture of membranes (PPROM), a leakage of amniotic fluid because of fetal membrane rupture occurring before 37 weeks’ gestational age, is seen in 2% to 3% of pregnancies. This has caused debate among clinicians on prevention, prediction, and management strategies.

Microbial invasion of the amniotic cavity (MIAC), characterized by microorganism presence in the amniotic fluid, is seen in 23% to 63% of PPROM cases. MIAC presence may coincide with changes in inflammatory mediators’ concentration, leading to certain clinical scenarios of PPROM.

Clinical scenarios of PPROM include intraamniotic infection, sterile intraamniotic inflammation, MIAC without inflammation, and with negative amniotic fluid for infection. Data has indicatedcervical excisional treatment of cervical intraepithelial neoplasia increases PPROM risk by about 250%.

There is little data on the association between PPROM cases and intraamniotic infection. To compare MIAC and intraamniotic infection rates among women with PPROM during pregnancy with and without cervical excision treatment history, investigators conducted a retrospective study including women with singleton pregnancies complicated by PPROM.

Participants included pregnant women admitted to the Department of Obstetrics and Gynecology, University Hospital Hradec Králové in the Czech Republic from January 2014 to December 2021. Eligibility criteria included singleton pregnancy, PPROM between 24+0 and 36+6 weeks, being aged 18 or more years, and having received transabdominal amniocentesis.

An ultrasound scan during the first trimester was used to determine gestational age, while PPROM was determined using observation of amniotic fluid pooling in the vaginal fornix. Intraamniotic environments were evaluated by transabdominal ultrasound-guided amniocentesis.

Antibiotics were used to treat PPROM, with intraamniotic inflammation being treated with a 7-day regimen of clarithromycin and PPROM without intraamniotic inflammation being treated with a 7-day regimen of intravenous benzylpenicillin. A positive test of MIAC led to modification of antibiotic therapy including corticosteroid therapy.

Five investigators determined cervical excisional treatment history by reviewing maternal and perinatal medical records. When cervical excisional treatment history was found, the patient was contacted by phone to request permission to collect further medical information. This included procedure data and technique, cone length, and cervical dysplasia severity.

Cone length, specified as cone height or cone depth, was measured in millimeters. Data on cone length was collected from pathologic reports. Short-term neonatal morbidity was also evaluated using neonatal medical records.

MIAC was determined by microorganism presence in amniotic fluid cell cultures, while intraamniotic inflammation was determined by IL-6 in the amniotic fluid of 745 pg/mL or more. Intraamniotic inflammation without MIAC was defined as sterile intraamniotic inflammation.

There were 765 women included in the final analysis, 26% of which had MIAC and 20% of which had intraamniotic inflammation. Of women, 14% presented with intraamniotic inflammation, 6% with sterile intraamniotic inflammation, 12% with MIAC without inflammation, and 68% with negative amniotic fluid for infection.

Cervical excisional treatment was found in 10% of women. These women often had increased maternal age, rates of chronic hypertension, acute histologic chorioamnionitis and funisitis, and corticosteroid administration. However, lower birthweights, gestational ages at admission and delivery, and smoking rates were seen in these women.

Rates of polymicrobial findings in the amniotic fluid did not significantly differ between women with and without cervical excisional treatment history. However, higher rates of MIAC, intraamniotic infection, and MIAC without inflammation were seen in women with a history of cervical excisional treatment, along with lower rates of negative amniotic fluid for infection.

A higher rate of intraamniotic infection was also seen in women with a cone length from 3 to 8 mm, while a higher rate of sterile intraamniotic inflammation was seen in women with a cone length from 13 to 17 mm. Those with a cone length of 18 to 32 mm had higher rates of MIAC, intraamniotic infection, and MIAC without inflammation.

An increased rate of early-onset neonatal sepsiswas seen in PPROM pregnancies with cervical excisional treatment history compared to PPROM pregnancies without that history. An association between cone length and the rate of early-onset neonatal sepsis was only seen in women with cone lengths from 18 to 32 mm.

These results indicated increased risks of intraamniotic infection, MIAC without inflammation, and early-onset neonatal sepsis from cervical excisional treatment history. Investigators recommended the increased risk of intraamniotic complications be considered in PPROM cases.

Reference

Kacerovsky M, Musilova I, Baresova S, et al.Cervical excisional treatment increases the risk of intraamniotic infection in subsequent pregnancy complicated by preterm prelabor rupture of membranes. American Journal of Obstetrics & Gynecology. 2023;229(1):51.E1-51.E13. doi:10.1016/j.ajog.2022.12.316