Kaisuke Ishihara

Anticipation of Uterine Bleeding in Placenta Previa Based on Vaginal Sonographic Evaluation

Objectives: The aim of this study was to predict massive uterine bleeding during pregnancy and cesarean section in women with placenta previa using transvaginal ultrasonography. Methods: Transvaginal ultrasonography was performed prospectively at and after 28 gestational weeks with follow-up scans at 5- to 7-day intervals until cesarean section in 35 women with placenta previa. The patients were classified into 3 groups based on the following sonographic features of the placental edge in relation to the internal cervical os: type A = two thirds of the placenta from the placental center overlapping the internal os (13 cases); type B = one third of the placenta from the periphery to outside overlapping the internal os (10 cases), and type C = echo-free space (EFS) in the placental edge overlapping the internal os (12 cases). In some cases of type-A placentas, lacunae with blood flow in the placenta from the basal plate to the chorionic plate were also observed. All types were further subdivided based on the presence or absence of associated sponge-like echo (S-echo) in the wall of the uterus adjacent to the placental location. In each type, the relation with the amount of bleeding during hospitalization and preterm delivery was examined. Results: Incidences of sudden massive bleeding during hospitalization were 7.7% (1/13), 10.0% (1/10), and 83.3% (10/12), in types A, B and C, respectively, being significantly higher in type C (p < 0.01). The risk of antepartum massive bleeding was also significantly higher in type C (p < 0.01). The incidence of preterm delivery due to sudden massive bleeding and the amount of bleeding during cesarean section were significantly higher in type A + S and type A + S with lacunae, respectively. Conclusions: Sonographic EFS in the lower edge of the placenta overlying the cervix indicates the risk of sudden massive antepartum bleeding. Furthermore, lacunae with sponge-like echo may also reflect the risk of massive bleeding at cesarean section. These findings warrant further observational studies to verify their clinical implications.

Detection of the Cervical Gland Area in Threatened Preterm Labor Using Transvaginal Sonography in the Assessment of Cervical Maturation and the Outcome of Pregnancy

Objectives: To detect the cervical gland area in threatened preterm labor, and to determine its detection rate and relationship with cervical maturation and outcome of pregnancy in preterm labor. Methods: This was a mixed longitudinal and cross-sectional study involving 615 transvaginal scans performed to detect the cervical gland area and measure cervical length in 101 singleton pregnancies with threatened preterm labor. The patients were treated with intravenous administration of ritodrine chloride for regular uterine contractions at 16–35 weeks of gestation. 260 normal singleton pregnancies served as controls. Simultaneously conventional digital examination was used to assess the cervical maturation index. The detection rates of the cervical gland area, measurements of cervical length by sonography, and assessment of the cervical maturation index by digital examination in threatened preterm labor were compared with those of normal singleton pregnancies. In the threatened labor group, the outcome of pregnancy was assessed according to the sonographic absence or presence of the cervical gland area. Results: In the normal pregnancy group, the detection rate of the cervical gland area remained practically constant until the 31st week of pregnancy (97%), but substantially decreased thereafter (70.2% in gestational weeks 32–35). In the threatened preterm labor group, the detection rate of the cervical gland area was constantly lower (44.5%) and the cervical maturation index was higher (4.65 score) than in the normal pregnancy group (83.1% and 1.80 score, respectively). The outcome of pregnancy in the threatened preterm labor group was poorer in the subgroup with the absence of a cervical gland area than in the subgroup with the presence of a cervical gland area (duration of pregnancy 257.0 vs. 271.0 days, birth weight 2,597.2 vs. 2,990.0 g, and admission to delivery interval 38.8 vs. 60.8 days). Highly significant correlations were noted among the detection rates of a cervical gland area and cervical length, cervical maturation index, and outcome of pregnancy. Conclusions: This study demonstrates for the first time that the sonographic absence of the cervical gland area reflects cervical maturation and could be considered as a predictor of threatened preterm labor and a sign of poor outcome of pregnancy in this condition.

P14Sonographic features of the cervix in the midtrimester as a predictor of preterm delivery

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