Prédiction de l’intervalle de latence par mesure échographique du col utérin dans la rupture prématurée des membranes avant terme

Abstract

Objective: To assess the value of ultrasonographic measurement of cervical length for predicting the duration of the latency period from admission to delivery in women with preterm premature rupture of the membranes (PROM). Method: Prospective study in 88 women with preterm PROM before 34 weeks of amenorrhea. The median gestational age at admission was of 30.1 weeks. The clinical management included: no digital examination of the uterine cervix, antenatal corticosteroids, antibiotics (amoxicillin & clavulanic acid) for 7 days, and hoding back until 34 weeks. Cervical length at admission was determined with transvaginal ultrasonography. The duration of the latency period was studied in relation with cervical length, serum C-reactive protein (CRP) level and white blood cell (WBC) count at admission. Results: The median latency period was longer in women with a cervical length ≥ 25mm (10 vs 5 days; p = 0.04), but this was not associated with a significant increase in birth weight. The median latency period was also longer in women with CRP < 20 mg/l (10 vs 3 days; p < 0.001) and this was associated with a significant increase in birth weight (1716 ± 549 vs 1201 ± 485 g ; p < 0.01). Moreover, increased CRP levels were more frequent in women with a cervical length < 25 mm, and cervical length was no more predictive of the duration of the latency period in the subgroup of women with CRP < 20 mg/l and WBC < 20 000 cells/mm 3. Conclusion: In women with preterm PROM, the latency period from admission to delivery is shorter when cervical length is < 25mm. However, the clinical value of transvaginal ultrasonography is limited in comparison with serum CRP.