Ultrasound examination at 37 weeks' gestation in the prediction of pregnancy outcome: the value of cervical assessment

Abstract

Objective To examine the potential value of routine measurement of cervical length in singleton low-risk pregnancies at 37 weeks of gestation in the prediction of onset and outcome of labor. of < 20, 21-30, 31-40 and 41-50 mm. In the pregnancies with spontaneous onset of labor the incidence of Cesarean section for failure to progress increased from 3.6% to 6. 0%, 6.4% and 11.8% for cervical lengths of < 20, 21-30, 31-40 and 41-50 mm, respectively Methods

Three‐dimensional ultrasound assessment of the cervix for predicting time to spontaneous onset of labor and time to delivery in prolonged pregnancy

“…However, irrespective of whether Bishop score and sonographic cervical length were used as single predicting variables or as one of several predicting variables in a logistic regression model, they changed the likelihood of the outcome very little or at most to only a moderate degree 17 . This is in agreement with the results of studies performed in term pregnancies 4,5,7 . Our results also showed that VI seemed to be related to the time to vaginal delivery in prolonged pregnancy, VI being higher in women giving birth ≤ 60 h than in those giving birth later (P = 0.05).…”

Reference data representative of normal findings at two‐dimensional and three‐dimensional gray‐scale ultrasound examination of the cervix from 17 to 41 weeks' gestation

“…Measurement of cervical length and anteroposterior (AP) diameter and assessment of the inner cervical os by two-dimensional (2D) TVS has been suggested as a method to predict preterm 2 -4 , term or post-term delivery 5,6 and outcome of labor induction 7,8 .…”

Cervical length and the risk of spontaneous labor at term

“…[8][9][10][11] Vimercati et al 8 in 2001 measured CL in 120 nulliparous women starting at 37 weeks and then weekly. They found that CL at 39 and at 40 weeks is shorter in women who delivered prior to 41 weeks.…”

“…These differences can be due to differences in patient population, ultrasound operators or simply chance. In 2003, Ramanathan et al 9 published their findings of CL at 37 weeks' gestation as a predictor of delivery after 40 weeks and 10 days. They found that CL of <20 mm at 37 weeks is associated with 0% incidence of delivery after 40 weeks and 10 days.…”

“…To date, four English language reports (all European) have assessed the relationship between CL at term (X37 weeks' gestation) and pregnancy outcomes. Three of these studies enrolled women at one specific week of gestation: two at 37 weeks 8,9 and one at 39-40 weeks. 10 Only one study enrolled women (N ¼ 93) between 37 and 40 weeks' gestation.…”