Clinical trial NCT02739503: Fetal Head Circumference as a Predictor of Operative Delivery
Official title: Fetal Head Circumference as a Predictor of Operative Delivery
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Pregnancy
Lead sponsor: Hillel Yaffe Medical Center
Sponsor class: OTHER_GOV
First posted: 2016-04-15
Enrollment: 500
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 45
Standard ages: ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Women at term (37+0 - 42+0 weeks' gestation)

Brief summary: This study set out to investigate whether antenatal ultrasound evaluation of the Fetal Head Circumference (FHC) could potentially possess a predictive role in determining women at increased risk for operative delivery or cesarean section.

Detailed description: When vaginal delivery poses a danger to the mother or newborn infant, operative delivery (instrumental or cesarean section) is indicated. Some specific indications for operative delivery include prolonged second-stage of labor, suspected compromise of the fetus, health-related disorders of the fetus or the mother that justify shortening of the second-stage of active labor and more. In cases where cephalo-pelvic disproportion (CPD) is suspected or when instrumental delivery is not possible or fails, cesarean section plays a critical role . Studies trying to identify women at greatest risk of CPD have concluded that neither x ray, nor computed tomography or magnetic resonance imaging have a proven value in labor management or in predicting clinical outcomes . Previous studies assessing fetal factors that are associated with operative delivery have focused mainly on estimated fetal weight to predict macrosomia. Nonetheless, ultrasound estimation of the fetal weight was shown to differ by as much as 20% from actual birth weight, and identifying cases with suspected fetal macrosomia, other than for diabetic pregnancies, was not found to improve labor outcome . As weeks may possibly elapse between the time of last antenatal assessment and onset of labor, a further challenge is related to the timing of ultrasound assessment. Several studies have shown an association between increased Fetal Head Circumference (FHC) and prolonged second-stage of labor, instrumental delivery and cesarean section . However, FHC can only be acquired following delivery and has no predictive value for interventions in labor.

Eligibility criteria: Inclusion Criteria:

1. Women at term (37+0 - 42+0 weeks' gestation)
2. Singleton pregnancies
3. Cephalic presentation
4. Anticipated vaginal delivery

Exclusion Criteria:

1. Younger than 18 years old and older than 45 years old
2. Women who incapable of providing informed consent

Primary outcomes:
measure: The rate of "operative delivery" including instrumental deliveries or cesarean sections.
timeFrame: 1 year
Secondary outcomes:
measure: Length (in hours) of the first and second stages of labor.
timeFrame: 1 year
measure: Rate of obstetric anal sphincter injury.
timeFrame: 1 year
measure: Rate of early postpartum hemorrhage (PPH).
timeFrame: 1 year
measure: Rate of neonatal trauma.
timeFrame: 1 year
measure: Rate of admission to the neonatal intensive care unit.
timeFrame: 1 year
Other outcomes:
Locations:
city: Hadera
country: Israel
facility: Department of Obstetrics and Gynecology, Hillel-Yaffe Medical Center
Study officials:
affiliation: Hillel Yaffe Medical Center
name: Ofer Limonad, M.D
role: PRINCIPAL_INVESTIGATOR
References:
citation: ACOG Practice Bulletin No. 154: Operative Vaginal Delivery. Obstet Gynecol. 2015 Nov;126(5):e56-e65. doi: 10.1097/AOG.0000000000001147. No abstract available.
citation: Murphy DJ, Liebling RE, Verity L, Swingler R, Patel R. Early maternal and neonatal morbidity associated with operative delivery in second stage of labour: a cohort study. Lancet. 2001 Oct 13;358(9289):1203-7. doi: 10.1016/S0140-6736(01)06341-3.
citation: Maharaj D. Assessing cephalopelvic disproportion: back to the basics. Obstet Gynecol Surv. 2010 Jun;65(6):387-95. doi: 10.1097/OGX.0b013e3181ecdf0c.
citation: Lenhard MS, Johnson TR, Weckbach S, Nikolaou K, Friese K, Hasbargen U. Pelvimetry revisited: analyzing cephalopelvic disproportion. Eur J Radiol. 2010 Jun;74(3):e107-11. doi: 10.1016/j.ejrad.2009.04.042. Epub 2009 May 13.
citation: Peregrine E, O'Brien P, Jauniaux E. Clinical and ultrasound estimation of birth weight prior to induction of labor at term. Ultrasound Obstet Gynecol. 2007 Mar;29(3):304-9. doi: 10.1002/uog.3949.
citation: Irion O, Boulvain M. Induction of labour for suspected fetal macrosomia. Cochrane Database Syst Rev. 2000;(2):CD000938. doi: 10.1002/14651858.CD000938.
citation: Elvander C, Hogberg U, Ekeus C. The influence of fetal head circumference on labor outcome: a population-based register study. Acta Obstet Gynecol Scand. 2012 Apr;91(4):470-5. doi: 10.1111/j.1600-0412.2012.01358.x. Epub 2012 Feb 28.
citation: Mujugira A, Osoti A, Deya R, Hawes SE, Phipps AI. Fetal head circumference, operative delivery, and fetal outcomes: a multi-ethnic population-based cohort study. BMC Pregnancy Childbirth. 2013 May 7;13:106. doi: 10.1186/1471-2393-13-106.
citation: Verburg BO, Steegers EA, De Ridder M, Snijders RJ, Smith E, Hofman A, Moll HA, Jaddoe VW, Witteman JC. New charts for ultrasound dating of pregnancy and assessment of fetal growth: longitudinal data from a population-based cohort study. Ultrasound Obstet Gynecol. 2008 Apr;31(4):388-96. doi: 10.1002/uog.5225.