A sonographic short cervix as the only clinical manifestation of intra-amniotic infection

Abstract

Objective: A sonographically short cervix is a powerful predictor of spontaneous preterm delivery. However, the etiology and optimal management of a patient with a short cervix in the mid-trimester of pregnancy remain uncertain. Microbial invasion of the amniotic cavity (MIAC) and intra-amniotic inflammation are frequently present in patients with spontaneous preterm labor or acute cervical insufficiency. This study was conducted to determine the rate of MIAC and intra-amniotic inflammation in patients with a cervical length -25 mm in the mid-trimester. Study design: A retrospective cohort study was conducted of patients referred to our high risk clinic because of a sonographic short cervix or a history of a previous preterm birth. Amniocenteses were performed for the evaluation of MIAC and for karyotype analysis in patients with a short cervix. Fluid was cultured for aerobic and anaerobic bacteria, as well as genital mycoplasmas. Patients with MIAC were treated with antibiotics selected by their physician. Results: Of 152 patients with a short cervix at 14-24 weeks, 57 had amniotic fluid analysis. The prevalence of MIAC was 9% (5/57). Among these patients, the rate of preterm delivery (-32 weeks) was 40% (2/5). Microorganisms isolated from amniotic fluid included Ureaplasma urealyticum (ns4) and Fusobacterium nucleatum (ns1). Patients with a positive culture for Ureaplasma urealyticum received intravenous Azithromycin. Three patients with Ureaplasma urealyticum had a sterile amniotic fluid culture after treatment, and subsequently delivered at term. The patient with Fusobacterium nucleatum developed clinical chorioamnionitis and was induced. Conclusion: (1) Sub-clinical MIAC was detected in 9% of patients with a sonographically short cervix (-25 mm); and (2) maternal parenteral treatment with antibiotics can eradicate MIAC caused by Ureaplasma urealyticum. This was associated with delivery at term in the three patients whose successful treatment was documented by microbiologic studies.

Cervical length for the prediction and prevention of preterm birth

“…Of those, 40% delivered before 32 weeks [53], underlying the relationship between inflammation/infection and sPTB.…”

Cervical length and the risk of microbial invasion of the amniotic cavity in women with preterm premature rupture of membranes

“…However, ultrasound can be used to safely assess cervical status in PPROM patients (12,29), and cervical length as determined by transvaginal ultrasonography in PPROM patients might predict the interval between admission and delivery (12,13,29). Moreover, recently, it has been reported that cervical length measurement usefully predicts microbial invasion of the amniotic cavity in women with preterm labor and intact membranes (14,15). In the present study, it was found that cervical length is a sensitive marker (sensitivity 85%; specificity 65%) of the presence of intra-amniotic microbial invasion in PPROM patients.…”

“…Iams et al found that a short cervix during pregnancy is an independent risk factor of the subsequent developments of clinical chorioamnionitis and neonatal sepsis (30). Hassan et al concluded that a short cervix is a clinical manifestation of intra-amniotic infection (14), and Gomez et al reported that a short cervix in women with preterm labor and intact membranes is a risk factor for microbial invasion of the amniotic cavity (15). Moreover, it has been reported that a short cervix in women with PPROM is a risk factor of imminent delivery (12,13).…”

“…Moreover, cervical length as determined by transvaginal ultrasound has emerged as a powerful means of predicting spontaneous preterm delivery in both women with preterm labor and intact membranes, and in women with PPROM (9)(10)(11)(12)(13). Recently, it was suggested that a short cervix in women with preterm labor and intact membranes is a risk factor for microbial invasion of the amniotic cavity (14,15). Therefore, we considered that if this is the case in women with preterm labor and intact membranes, it is possible that women with PPROM and a shorter cervix may also be at greater risk of microbial invasion of amniotic cavity.…”

Factores asociados con el parto prematuro entre 22 y 34 semanas en un hospital público de Santiago

“…Embarazo con algunas de las siguientes condiciones clínicas presentes sugerentes de infección intrauterina: RPM, corioamnionitis clínica, sangrado vaginal con desprendimiento amniocorial, infección cér-vicovaginal (ICV) especialmente por Streptococcus Grupo B (SGB), infección del tracto urinario (ITU), dispositivo intrauterino (DIU) no extraí-do, placenta previa con sangrado vaginal, cérvix menor de 15 mm medido por ultrasonografía, desprendimiento prematuro de placenta normoinserta (DPPNI), membranas prolapsadas bajo el orificio cervical externo (MPr) [25][26][27][28][29][30][31][32] y asociado con los siguientes marcadores histopatológicos placentarios específicos: corioamnionitis aguda, funisitis aguda [5][6][7][8][9][10][11][12] . b) Enfermedades maternas Hipertensión arterial.…”