Fetal Clavicular Measurement to Predict Fetal Macrosomia

Official title

Fetal Clavicular Measurement to Predict Fetal Macrosomia: A Prospective Cohort Study

Overview

Macrosomia is associated with increased risks for both the mother and the baby, including complications during delivery, injuries, and even death. The accurate diagnosis of macrosomia is often difficult before birth. There are a number of factors that can increase the risk of macrosomia, such as maternal obesity, diabetes, and excessive weight gain during pregnancy. There are also a number of different techniques that can be used to try to predict macrosomia, but none of them are perfect. The aim of this study is to evaluate sensitivity of measuring fetal clavicle length in third trimester compared with biacromial diameter and Hadlock formula IV for prediction of fetal macrosomia.

Detailed description

Two terms are applied for fetal overgrowth, Large for gestational age (LGA) meaning fetal birth weight (BW) more than 90th percentile for specific gestational age while macrosomia is an absolute value regardless of gestational age which historically defined as 4000-4500 gm. Those two groups have increased risks for neonatal and maternal complications compared to general population and increase sharply when BW \>4500gm, the risks of macrosomia are continuum without threshold defining safe and risky outcome, some authors classify macrosomia into 3 grades, grade 1 (4000gm-4499gm), grade 2(4500-4999), grade 3 (≥5000gm).

Despite its implications, the accurate diagnosis is after birth and its prenatal prediction is poor although published formulas for estimating fetal weight shows correlation with BW, however the variability of the estimate is up to 20% with most of formulas, meta-analysis of 29 studies showed sensitivity of 56% and specificity of 92% in predicting BW ≥ 4000gm accuracy of ultrasound decreases with increasing BW, BW\>4500 accurate prediction is only 33-44 % of cases. Given the poor predictability of macrosomia, variety of other techniques and formulas are investigated, neither repeated US examination nor growth curves improves predictability, Youssef's formula measuring biacromial diameter (distance by between both acromial processes which joins clavicles at acromioclavicular joints) and macrosomic specific formula seems to be predictive. In study evaluating clavicle length for shoulder dystocia, it found that measuring clavicle was significant for macrosomia however the limitation is small sample size and its comparison with other fetal biometrics may be needed.

Interventions

• Device Obstetric Ultrasound
  Measuring fetal clavicular length and estimated fetal weight using Hadlock IV formula and Youssef's formula.

Primary outcome measures

• Third trimester clavicle length measurement [Time frame: 37-42 weeks of gestation]

Secondary outcome measures (8)

• Establish the relationship between third-trimester clavicle length and shoulder dystocia [Time frame: Immediately after delivery - postprocedure]
• Mode of delivery [Time frame: At the day of delivery]
• Gestational age at the time of delivery. [Time frame: At the day of delivery]
• Neonatal Apgar score. [Time frame: postpartum with 1 and 5 minutes]
• Neonatal bi-acromial diameter [Time frame: postpartum within 1 to 5 minutes]
• Neonatal birth weight [Time frame: postpartum within 1 to 5 minutes]
• Neonatal need for NICU [Time frame: postpartum within 1 minutes to 5 minutes]
• Neonatal actual clavicle length [Time frame: postpartum within 1 minutes to 5 minutes]

Eligibility criteria

Inclusion criteria

• Singleton pregnancy.
• Gestational age between 37-42 weeks.
• Accepting to be included in the study.

Exclusion criteria

• Congenital fetal malformation affecting birth weight or affecting clavicle.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model

Cohort

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Barth WH, Jackson R. ACOG PRACTICE BULLETIN Clinical Management Guidelines for Obstetrician-Gynecologists. American collage of obstetricians and gynocologists [Internet]. 2020 Jan;135:18-35. Available from: http://journals.lww.com/greenjournal
• Nesbitt TS, Gilbert WM, Herrchen B. Shoulder dystocia and associated risk factors with macrosomic infants born in California. Am J Obstet Gynecol. 1998 Aug;179(2):476-80. doi: 10.1016/s0002-9378(98)70382-5. PMID 9731856
• Boulet SL, Alexander GR, Salihu HM, Pass M. Macrosomic births in the united states: determinants, outcomes, and proposed grades of risk. Am J Obstet Gynecol. 2003 May;188(5):1372-8. doi: 10.1067/mob.2003.302. PMID 12748514
• Zhang X, Decker A, Platt RW, Kramer MS. How big is too big? The perinatal consequences of fetal macrosomia. Am J Obstet Gynecol. 2008 May;198(5):517.e1-6. doi: 10.1016/j.ajog.2007.12.005. PMID 18455528
• Doty MS, Chen HY, Sibai BM, Chauhan SP. Maternal and Neonatal Morbidity Associated With Early Term Delivery of Large-for-Gestational-Age But Nonmacrosomic Neonates. Obstet Gynecol. 2019 Jun;133(6):1160-1166. doi: 10.1097/AOG.0000000000003285. PMID 31135729
• Hadlock FP, Deter RL, Harrist RB, Park SK. Estimating fetal age: computer-assisted analysis of multiple fetal growth parameters. Radiology. 1984 Aug;152(2):497-501. doi: 10.1148/radiology.152.2.6739822. PMID 6739822
• Malin GL, Bugg GJ, Takwoingi Y, Thornton JG, Jones NW. Antenatal magnetic resonance imaging versus ultrasound for predicting neonatal macrosomia: a systematic review and meta-analysis. BJOG. 2016 Jan;123(1):77-88. doi: 10.1111/1471-0528.13517. Epub 2015 Jul 29. PMID 26224221
• Scioscia M, Vimercati A, Ceci O, Vicino M, Selvaggi LE. Estimation of birth weight by two-dimensional ultrasonography: a critical appraisal of its accuracy. Obstet Gynecol. 2008 Jan;111(1):57-65. doi: 10.1097/01.AOG.0000296656.81143.e6. PMID 18165393

Identifiers

NCT: NCT06283277 · fetal macrosomia

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗