Effect of epidural analgesia on cervical ripening using dinoprostone vaginal inserts.

OBJECTIVE: To clarify whether the duration from cervical ripening induction to labor onset is prolonged when epidural analgesia is administered following application of dinoprostone vaginal inserts vs. cervical ripening balloon. METHODS: This retrospective study included mothers with singleton deliveries at a single center between 2020-2021. Nulliparous women who underwent labor induction and requested epidural analgesia during labor after 37 weeks of gestation were included. The duration from cervical ripening induction to labor onset was compared between women using a dinoprostone vaginal insert and those using a cervical ripening balloon and between women who received epidural analgesia before and after labor onset. RESULTS: In the dinoprostone vaginal insert group, the duration was significantly shorter in the subgroup that received epidural analgesia after labor onset (estimated median, 545 [95% confidence interval: 229-861 min]) than the subgroup that received it before labor onset (estimated median, 1,570 [95% confidence interval: 1,226-1,914] min, p = 0.004). However, in the cervical ripening balloon group, the difference between subgroups was not significant. The length of labor among the groups was also not significantly different. CONCLUSION: Epidural analgesia as labor relaxant adversely affected the progression of uterine cervical ripening when dinoprostone vaginal inserts were used, whereas it did not affect cervical ripening when a mechanical cervical dilatation balloon was used. The present results are significant for choosing the appropriate ripening method.

Optimal cervical-ripening method for labor induction in Japan after the era of controlled-release dinoprostone vaginal insert.

OBJECTIVE: To investigate the predictive value of obstetric findings when using dinoprostone (prostaglandin E2 [PGE2]) vaginal inserts for cervical ripening, and to assess the optimal cervical-ripening method between PGE2 vaginal insert and/or cervical dilators. METHODS: This prospective observational study enrolled pregnant women who underwent cervical ripening for labor induction in 37-41 week' gestation in 2020. In evaluation 1, optimal obstetric findings predictive of rapid cervical ripening using PGE2 were assessed. In evaluation 2, the duration from PGE2 administration to labor onset and perinatal outcomes were compared between cases in which only PGE2 was used and cases that were treated with PGE2 after mechanical cervical dilators (Dilapan®) for extremely immature cervical ripening (uterine cervical os <2 cm). RESULTS: In evaluation 1, uterine dilatation before the use of a PGE2 vaginal insert was mostly correlated with the time from PGE2 administration to labor onset (r = -0.428, p < 0.001). When the uterine cervical os dilatation was ≥2 cm, a shorter time-to-labor onset was found. In addition, os dilatation, effacement, and station at the time of PGE2 vaginal insert removal also significantly progressed. In evaluation 2, the median duration from PGE2 administration to labor onset was 1740 min in cases where only PGE2 was used, and 610 min in those where PGE2 was used after mechanical cervical dilators (p = 0.011). CONCLUSION: PGE2 vaginal inserts are relatively effective when the uterine cervical os is ≥2 cm in diameter. However, in cases of extremely immature cervical-ripening, it was feasible to use PGE2 vaginal inserts before mechanical cervical dilatation.

Individualized management of vasa previa and neonatal outcomes.

OBJECTIVE: To describe our individualized management protocol for women with an antenatal diagnosis of vasa previa (VP) and to report maternal and neonatal outcomes in patients managed according to our protocol. METHODS: A retrospective study of prospectively collected data of antenatally diagnosed VP managed at our hospital between 2014 and 2021. Obstetric and neonatal outcomes were reviewed and analyzed. RESULTS: Fourteen cases of antenatally diagnosed VP in 5150 total deliveries were analyzed (0.3%) Five cases (36%) of VP were diagnosed during the routine fetal morphological ultrasound screening, and nine cases (64%) were referred to our hospital due to perinatal complications. There were nine cases that required hospitalization (due to fetal growth restriction [FGR] [1], preterm labor [3], patients' request [5]). The other five were asymptomatic. Eight patients were delivered by scheduled cesarean section at around 36 weeks and only three neonates were admitted to NICU with transient tachypnea of newborn. However, six patients required CS before the scheduled dates because of other complications (preterm labor [3], abnormal cardiotocogram patterns [1], FGR [1] and twin pregnancy [1]). Four neonates born by CS before their scheduled dates were admitted to NICU. No cases required prolonged hospitalization and there were no serious neonatal complications. CONCLUSION: Individualized management may lead to favorable outcomes with VP. Outpatient management may be considered in patients without risk factors. However, maternal hospitalization and earlier scheduled CS should be considered in symptomatic patients or those at risk for preterm delivery.

Declaration of emergency state due to COVID-19 spread in Japan reduced maternal transports without reduction in preterm delivery.

INTRODUCTION: To clarify whether the declaration of an emergency state due to the spread of COVID-19 in Japan affected the number of maternal transports and premature births. METHODS: A questionnaire-based descriptive study was conducted in perinatal centers throughout Japan in 2020. The incidence of maternal transport and preterm delivery rates every month after the COVID-19 spread in 2020 were compared with those in 2019. RESULTS: Participants were recruited from 52 perinatal centres. The maternal transport rate (maternal transports per number of deliveries) was 10.6% in April and 11.0% in June 2020, compared with 12.5% in 2019 (P < 0.05). The maternal transport rate due to preterm labor was 4.8% in April 2020 and 5.8% in 2019 (P < 0.05). The maternal transport rate during the declaration of emergency state decreased by 21% in April 2020 in non-emergency-declared prefectures, and decreased by 17% in May 2020 in emergency-declared prefectures. However, there was no significant difference in the preterm delivery rate between 2020 and 2019, regardless of the prefecture and gestational period. CONCLUSION: Declaration of the emergency status due to COVID-19 spread in Japan reduced maternal transport due to preterm labor, but did not reduce preterm delivery itself.

Ultrasonographic findings of placental abruption observed on superb microvascular imaging.

OBJECTIVE: To demonstrate ultrasound pathological findings of placental abruption (PA) detected using a new Doppler method: superb microvascular imaging (SMI). CASE REPORT: The patient was a pregnant woman with dark brown vaginal discharge at 32 + 4 weeks of gestation. Conventional ultrasound revealed an exophytic heterogeneous area measuring 3 cm, between the placenta and myometrium. SMI showed no minor blood flow inside the area. A diagnosis of marginal sub-chorionic hematoma was made. On the seventh day of hospitalization, SMI showed pulsation of blood flow in the inter-villous space and fetal blood flow in the villous trees. Due to an increase in the frequency of uterine contractions, an emergency cesarean section was performed. Histopathological examination showed hematomas beneath the decidual tissue, and the decidual layer was undamaged. The inter-villous space was preserved. CONCLUSION: SMI can contribute to a more accurate PA diagnosis that may lead to timely administration of obstetric intervention.

Histological Assessment of the Placenta Accreta Spectrum Diagnosed with a 33-MHz Linear Probe during Cesarean Section.

As placenta accreta spectrum (PAS) pathologies affect only the extremely thin tissues between the placenta and the uterine myometrium, superficial endometrial damage such as that caused by placenta creta and increta can be diagnosed only through histopathology. We performed direct uterine ultrasound of PAS using an ultrahigh frequency (33 MHz; i33LX9 Aplio i800) linear transducer. Here, we describe two cases with ultrasound images of placentas with PAS and a case without PAS to compare histological findings. In cases of PAS at the previous Cesarean scar, ultrasonography clearly revealed a thin uterine myometrium with some island-shaped sites where placental tissue was focally anchored to the uterine myometrium near the scar. Speckle blood flow pattern was absent at these sites during scanning with B-mode, but was detectable elsewhere. Histopathology samples from the same site revealed that villous tissue was directly attached to the uterine myometrium with a large area of infarction. In another case of diffuse PAS, speckle blood flow pattern was generally absent, and histopathology revealed deep fibrinoid deposits. We believe that histological evaluation following ultrasound use will improve the accuracy of ultrasound diagnosis and perinatal management of PAS in clinical practice.

Novel ultrasound assessment of placental pathological function using superb microvascular imaging.

Ultrasound Doppler method of Superb Microvascular Imaging (SMI) can significantly visualize low-velocity blood flow using a unique algorithm. We scanned placenta antenatally using SMI and compared those findings with histological findings after delivery in cases with placental abnormalities. In normal, SMI expresses stem villous vessels connecting to the tertiary villous vessels which are sharply diminished, and expresses intervillous blood flow as "scatter." Placental infarction was expressed as an anechoic area in SMI. Avascular villi was expressed as absent villous blood trees in a background scatter flow in SMI. In this report, we demonstrated typical SMI findings of the pathologic placenta as a pilot study.

Degenerative type of placental chorioangioma requiring fetal blood transfusion.

We experienced a case with fetal hydrops, polyhydramnios, and a well-defined oval anechoic lesion of approximately 9 cm in size, without blood flow at 26 weeks' gestation. As increased middle cerebral artery peak systolic velocity, the fetal hydrops was caused by a placental tumor such as a chorioangioma; however, the tumor was atypical. Fetal blood hemoglobin was 8.3 g/dl on percutaneous umbilical cord blood sampling. After erythrocytes transfusion to the fetus, the mother normally delivered at 38 weeks' gestation. The placental tumor was histologically diagnosed as a necrotic chorioangioma. Obstetricians should note such atypical chorioangiomas when differential diagnosis of placental tumors.

Accuracy of predicting neonatal distress using a five-level classification of fetal heart rate monitoring.

AIM: To assess the accuracy of neonatal distress prediction using the five-level classification of fetal heart rate (FHR) and management protocol of the Japan Society of Obstetrics and Gynecology (JSOG). METHODS: A case-control study was conducted. Vertex singleton pregnant women who delivered after 37 weeks' gestation from 2013 to 2015 were enrolled. The participants were categorized into two groups; controls were levels 1-3 (n = 1184), whereas cases were levels 4-5 (n = 117) group. Neonatal distress was defined as Apgar score < 8 points at 5 min or umbilical cord artery pH < 7.1. RESULTS: There were 117 cases (9.0%). The frequency of the neonatal distress was observed in 1.3% controls and 6.8% cases (P < 0.01). Diagnostic accuracy of neonatal distress for cases showed a 6.8% positive-predictive value, 34.8% sensitivity, 91.5% specificity and 98.7% negative-predictive value. Among various obstetrical conditions, high sensitivity (100%) for prediction of neonatal distress was observed in women with chromosome abnormalities, placental abruption, umbilical cord abnormalities and excessive labor pain. Conversely, relatively low specificity (<50%) was observed in cases with oligohydramnios and excessive labor pain. CONCLUSION: The five-level classification scheme was efficient for neonatal distress prediction. However, depending on the obstetric condition, the FHR findings and neonatal condition might be independent.

Ultrasound screening and management of vasa previa in Japan.

AIM: This study aimed to clarify ultrasound screening and management for vasa previa (VP) in perinatal centers and primary facilities in Japan. METHODS: A questionnaire survey about antepartum ultrasound screening and management for VP was delivered in 2018. Questions were sent by email or post to perinatal centers and randomly selected primary hospitals or clinics throughout Japan. RESULTS: Seventy-seven perinatal centers and 300 primary facilities answered. VP was screened in 85.7% of perinatal centers and 81.3% of primary facilities. The reported incidence of VP was 0.05% (86/158 323) and 0.05% (28/54 791) in perinatal centers and primary facilities, respectively. When patients were diagnosed with VP, 88.7% of primary facilities referred the patient to a tertiary hospital. Routine hospitalization (100%) and steroid administration (46%) were frequently performed in perinatal centers. The median gestational age at planned cesarean section was significantly earlier in perinatal centers (34 weeks) than in primary facilities (37 weeks). Of the 31 reported cases of VP, 30 were reported as intact survival, but 1 case required an emergency cesarean section at 38 weeks of gestation without an antenatal diagnosis, resulting in neonatal death. CONCLUSION: More than 80% of obstetric facilities both perinatal centers and clinics in Japan perform ultrasound screening with for VP with similar detection rate. However, to further improve perinatal outcomes related to VP, pathophysiology and diagnosis of VP should be more widely recognized by obstetric caregivers throughout Japan.