Étude préliminaire du diagnostic d’engagement par une échographie transpérinéale avant une extraction instrumentale

[Are ultrasound measurements of the cervical length and fetal head-perineum distance predictive of delivery outcome in post-term pregnancies?]

OBJECTIVE

Post-term pregnancy is frequently associated with higher fetal and maternal morbidity and mortality. Its management essentially depends on clinical cervical characteristics as evaluated by the Bishop score (BS). However, BS is poorly predictive of the delivery outcome. We sought to demonstrate that ultrasound measurement of cervical length and evaluation of fetal height could predict the outcome in post-term pregnancies.

METHODS

A prospective single center study was undertaken between the 21st of January and the 1st of June 2013. Fetal height was measured using a transperineal technique and cervical length was evaluated by a vaginal ultrasound on patients consulting and their term date. C-section rates were considered to be the primary judgment criteria.

RESULTS

A total of 136 patients were included. C-section rates in this population was 19%. Fetal height and cervical length were not different between the C-section group and the vaginal delivery group.

CONCLUSION

Our study demonstrates that ultrasound measurement of cervical length and fetal height do not show better results than BS in predicting the outcome of post-term pregnancy. Combining these ultrasound measurements has already been suggested in other studies and promising results have been shown. More studies are necessary to further these results.

[Instrumental delivery with perineum-fetal head distance >55 MM on ultrasound]

OBJECTIVE

Compare the issue of an operative vaginal delivery associated to the fetal presentation diagnosed by transperineal ultrasound. Three groups were formed: ≥55 mm, between 45 and 55 mm, and <45 mm.

METHODS

A monocentric prospective study on 108 patients has been conducted between April 2011 and August 2014. The distance between perinea and skull has been analyzed to compare the success of operative vaginal delivery considering the level of the fetal presentation in the pelvic cavity.

RESULTS

The failed operative vaginal deliveries are more frequent while the fetal head is above 55 mm (16.7%) or while the fetal head is between 45 and 55 mm (9.1%) than while the fetal skull is under 45 mm (1.8%) (P=0.04). However there is no significant difference for the fetal shoulder dystocia (5.6% vs 3.0% vs 3.5%, P=0.5), nor for the newborn outcomes (16.7 vs 15.2 vs 14; P=0.9).

CONCLUSION

Despite the high rate of failed operative vaginal delivery above 55 mm, it should be considered not to prohibit but send free to the obstetrician appreciation.

[Correlation between the perineal-to-skull measurement by tranperineal ultrasound, failure of vaginal operative delivery and maternal-fetal morbidity]

OBJECTIVES

To assess the influence of the perineal-to-skull measurement by tranperineal ultrasound (TPU) on the outcome of vaginal operative extraction together with maternal and fetal morbidity.

MATERIALS AND METHODS

Retrospective, monocentric and descriptive study was done on 272 patients, from 2009 January 1st to 2009 December 31st. It compares the failure rate of instrumental extraction, total caesarean section rate together with the maternal morbidity (type of perineal tears and post-partum hemorrhage rate) and fetal morbidity (5' Apgar score, arterial pH, transfer in neonatal intensive care unit) to the values obtained with TPU.

RESULTS

There is a correlation between the perineal-to-skull measurements higher or equal to 50mm at TPU and the instrumental failure rate (<50mm 0.8% vs. ≥50mm 11.9%; P<0.0001), caesarean (0.9% vs. 33.3%; P<0.0001), post-partum haemorrhage (3% vs. 11.9%; P=0.02), et paediatric intervention (16.7% vs. 31%; P=0.03).

CONCLUSION

Perineal-to-skull distance measured with TPU higher or equal to 50mm is at risk of instrumental failure and maternal morbidity. Associated with clinical examination and usual obstetrical risk factors, TPU could be useful to the decision between operative vaginal delivery and prophylactic caesarean section.