Ultrasound assessment of fetal head-perineum distance before induction of labor.

OBJECTIVES: To evaluate fetal head-perineum distance measured by ultrasound imaging as a predictive factor for induction of labor, and to compare this distance with maternal factors, the Bishop score and ultrasound measurements of cervical length, cervical angle and occiput position. METHODS: The study included 275 women admitted for induction of labor. The fetal head-perineum distance was measured by transperineal ultrasound imaging as the shortest distance from the outer bony limit of the fetal skull to the skin surface of the perineum. Cervical length and angle was measured by transvaginal ultrasound examination, and fetal head position was assessed by transabdominal ultrasound imaging. The Bishop score was assessed without knowledge of ultrasound measurements. Receiver-operating characteristics (ROC) curves were used for evaluation of the probability of a successful vaginal delivery. The time from induction to delivery was tested using Cox regression analysis with ultrasound measurements, parity and body mass index (BMI) as possible predictive factors. RESULTS: Areas under the ROC curve for prediction of vaginal delivery were 62% (95% CI, 52-71%) for fetal head-perineum distance (P = 0.03), 61% (95% CI, 51-71%) for cervical length (P = 0.03), 63% (95% CI, 52-74%) for cervical angle (P = 0.02), 61% (95% CI, 52-70%) for Bishop score (P = 0.03) and 60% (95% CI, 51-69%) for BMI (P = 0.05). The Cesarean delivery rate was 22% among nulliparous and 5% among parous women (P < 0.01). Parity, fetal head-perineum distance, cervical length and cervical angle were contributing factors predicting vaginal delivery within 24 h in a Cox regression model. Occiput posterior position had no significant predictive value. CONCLUSIONS: Fetal head-perineum distance measured by transperineal ultrasound examination can predict vaginal delivery after induction of labor, with a predictive value similar to that of ultrasonographically measured cervical length and the Bishop score. However, we judge none of these methods used alone to be good enough in a clinical setting.

Prediction of labour and delivery by ascertaining the fetal head position with transabdominal ultrasound in pregnancies with prelabour rupture of membranes after 37 weeks.

PURPOSE: To evaluate the proportion of fetal head rotation from occiput posterior (OP) to occiput anterior (OA) during labour after term prelabour rupture of membranes (PROM), and to study if OP before labour are associated with a higher risk of operative deliveries and a longer duration of labour. MATERIALS AND METHODS: A transabdominal ultrasound examination was performed in 152 women with PROM after 37 weeks with a single live fetus in cephalic position. The course of labour was compared in women with the fetal head in occiput posterior position or other positions before the start of labour. RESULTS: Before the start of labour, 40 (26%) fetuses were in occiput posterior position (OP), but 34 (85%) of them rotated to occiput anterior (OA) during labour. Ten (6.6%) fetuses were delivered in OP, and six of them were in OP before the start of labour. There were no statistically significant associations between the head position before the start of labour and the duration from PROM to delivery, induction of labour, use of epidural analgesia, augmentation with oxytocin, operative deliveries, perineal tears, Apgar scores, pH or base excess in the umbilical artery. CONCLUSIONS: Transabdominal ultrasound examination can determine the fetal head position before the start of labour, but the position of the head did not predict the course of labour, probably because the fetal head may rotate during labour even after PROM.

Prediction of labor and delivery by transperineal ultrasound in pregnancies with prelabor rupture of membranes at term.

OBJECTIVE: To evaluate whether engagement of the fetal head or cervical length in women with premature rupture of membranes (PROM) at term, are associated with time from PROM to delivery or need for operative delivery. METHODS: A transperineal ultrasound examination was performed in 152 women with a single live fetus in cephalic presentation after PROM (at > 37 gestational weeks). The shortest distance from the outer bony limit of the fetal skull to the skin surface of the perineum was measured in a transverse view, and the cervical length was measured in a sagittal view. The time from PROM to delivery was tested in a Cox regression analysis with ultrasound measurements, parity, maternal age, body mass index and birth weight as possible predictive factors. RESULTS: The head-perineal distance was associated with the time from PROM to delivery (log rank test, P < 0.001). Thirty-six hours after PROM, 32% (95% CI, 15-49) of women with a short head-perineal distance (< 45 mm) and 43% (95% CI, 24-62) of women with a long distance (> or = 45 mm) were still in labor. Women with a short head-perineal distance had fewer Cesarean sections, less use of epidural analgesia and a shorter time in active labor, and their babies had a higher pH in the umbilical artery. The measured cervical length was not associated independently with time to delivery. CONCLUSION: Transperineal ultrasound measurements of fetal head engagement may help clinicians to predict the course of labor in women with PROM.

[Hemorrhage after vaginal delivery]. / Blødning etter vaginal fødsel.

BACKGROUND: Primary postpartum haemorrhage, defined as blood loss of more than 500 ml, is an important cause of maternal morbidity and mortality. MATERIAL AND METHODS: By the use of information registered in a database in 1997-99 at Rogaland Central Hospital 11,681 women with vaginal births were investigated. In 1997 all women received 10 IU oxytocin routinely after delivery, in 1998 and 1999 the use of oxytocin was restricted to special indications. RESULTS: Mean bleeding was 363 ml, 1,123 women (9.6%) had a blood loss of more than 500 ml, and 91 (0.8%) of more than 1,500 ml. First delivery, twins, big baby, induction of labour, epidural analgesia, operative vaginal delivery, episiotomy and tears were associated with increased bleeding. INTERPRETATION: The risk of postpartum haemorrhage seems to be increased with restricted use of oxytocin after delivery.

[Hemorrhage after Cesarean section]. / Blødning ved keisersnitt.

BACKGROUND: Caesarean delivery may cause serious complications; haemorrhage is one of them. MATERIAL AND METHODS: By the use of information registered in a database in 1997-99 at Rogaland Central Hospital, 978 cesarean deliveries were investigated. RESULTS: Mean bleeding was 460 ml. 203 (20.8%) women had a blood loss of more than 500 ml and 17 (1.7%) of more than 1,500 ml. Multiple pregnancies, acute caesarean, general anaesthesia, increasing age of mother, high birth-weight, low gestational age, placenta praevia, abruptio placentae and arrest of delivery progression were associated with increased bleeding. INTERPRETATION: Several identifiable factors are associated with increased blood loss after caesarean delivery. Serious blood loss is rare.