Protocol - Fetal Growth Assessment - Percentiles for U.S. Populations
Description
Determination of fetal growth is a three-step process:
Step 1: Ascertainment of estimated fetal weight (EFW)
Step 2: Verification of gestational age (GA) at which the EFW was recorded
Step 3: Determination of EFW or biometry percentiles by plotting the EFW or relevant biometric measures at the appropriate GA on a pre-defined fetal growth curve
Specific Instructions
Utilization of Fetal Growth Standards based on the Fetal Growth Longitudinal Study (FGLS) is recommended. Another protocol used in international settings, the INTERGROWTH 21st Fetal Growth Standards, is available in Supplemental Information.
Availability
Protocol
1. Ascertainment of Estimated Fetal Weight (EFW)
The investigator is encouraged to utilize one of the following approaches for documentation of EFW. Approach (a) is the preferred approach for retrospective studies, although it is recognized that biometric data may be less easily accessible in retrospective investigations, and as such approach (b) is provided as an alternative.
(a) EFW (preferably in grams) derived by review of available ultrasound reports to obtain relevant biometric measures (bi-parietal diameter [BPD], head circumference [HC], abdominal circumference [AC], and femur length [FL]), followed by calculation of EFW from formula provided by Hadlock (see Hadlock et al., 1985).
Date of ultrasound: ____________________ (DD/MMM/YYYY)
Gestational Age: ________ weeks ________ days (as per protocol for GA)
Biometric measures as they appear on the ultrasound report:
Bi-parietal diameter (BPD): __________ mm
Head circumference (HC): ___________ mm
Abdominal circumference (AC): ___________ mm
Femur length (FL): ___________ mm
Estimated Fetal Weight (EFW): ________________ grams
(b) EFW (preferably in grams) abstracted from ultrasound report contained within the medical record:
Date of ultrasound: ____________________ (DD/MMM/YYYY)
Gestational Age: ________ weeks ________ days (as per protocol for GA)
Estimated Fetal Weight: ________________ grams
2. Verification of Gestational Age (GA)
The PhenX measure for Gestational Age - Medical Record Abstraction is considered essential for interpretation of this measure.
3. Plotting the EFW or Biometric Measures - US populations
Determination of fetal growth should then be undertaken, by plotting EFW or biometric measures on a growth curve, allowing for determination of percentiles, by using the following protocol:
NICHD Fetal Growth Studies
*An SR of 11 methods of EFW assessment did not identify a superior formula; given that Hadlock (1985) is the most widely used formula, it may provide the greatest degree of consistency across studies
Once biometric measures and gestational age have been obtained using one of the approaches described, the investigator should consult the Fetal Growth Standard established via the NICHD Fetal Growth Studies, to determine the specific, ethnicity-specific, EFW percentile. See Table 2 in the Buck Louis et al. 2015 publication for the EFW percentiles of the different ethnicities.
Personnel and Training Required
Personnel who are trained in performing medical records review.
Equipment Needs
None
Requirements
| Requirement Category | Required |
|---|---|
| Major equipment | No |
| Specialized training | No |
| Specialized requirements for biospecimen collection | No |
| Average time of greater than 15 minutes in an unaffected individual | No |
Mode of Administration
Medical record abstraction
Lifestage
Adolescent, Adult, Pregnancy
Participants
Pregnant women aged 18-40
Selection Rationale
This is a robust methodology, accounting for ethnic differences in fetal growth in the United States. The protocol is accessible and easy to use. The formula chosen to calculate estimated fetal weight (EFW), which was then used to develop the fetal growth percentiles, is well-known and widely-available. Researchers searching for a protocol for fetal growth assessment can apply this formula with ease to calculate the EFW for their study, using biometry measures as described above, to be plotted on the available Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) growth curves.
This measure was derived from prospective follow-up of healthy women with low-risk, singleton pregnancies from 12 community and perinatal centers in the United States, including non-Hispanic whites, non-Hispanic blacks, Hispanics, and Asians. Women were screened from 8+0 to 13+6 weeks gestational age (GA) for maternal health status associated with presumably normal fetal growth (aged 18-40 years, body mass index [BMI] 19.0-29.9 kg/m2, healthy lifestyles and living conditions, low-risk medical and obstetrical history). The fetuses of 74% of women continued to be low risk (uncomplicated pregnancy, absent anomalies) at birth, and their measurements were included in the standards.
Language
English
Standards
| Standard | Name | ID | Source |
|---|---|---|---|
| caDSR Form | PhenX PX241501 - Fetal Growth Assessment Percentiles For Us Populatio | 6873323 | caDSR Form |
Derived Variables
None
Process and Review
Not applicable.
Protocol Name from Source
Hadlock, F.P., et al. Racial/ethnic standards for fetal groth: the NICHD Fetal Growth Studies. Am J Obstet Gynecol, 2015
Source
Buck Louis, G. M., Grewal, J., Albert, P. S., Sciscione, A., Wing, D. A., Grobman, W. A., Newman, R. B., Wapner, R., DAlton, M. E., Skupski, D., Nageotte, M. P., Ranzini, A. C., Owen, J., Chien, E. K., Craigo, S., Hediger, M. L., Kim, S., Zhang, C., & Grantz, K. L. (2015). Racial/ethnic standards for fetal growth: the NICHD Fetal Growth Studies. American Journal of Obstetrics & Gynecology, 213(4), 449.e441-449.e441.
Hadlock, F. P., Harrist, R. B., Sharman, R. S., Deter, R. L., & Park, S. K. (1985). Estimation of fetal weight using head, body and femur measurements - a prospective study. American Journal of Obstetrics & Gynecology, 151, 333-337.
General References
Bricker, L., Neilson, J. P., & Dowswell, T. (2008). Routine ultrasound in late pregnancy (after 24 weeks gestation). The Cochrane Database of Systematic Reviews, 4, CD001451.
Conde-Agudelo, A., Papageorghiou, A. T., Kennedy, S. H., & Villar, J. (2013). Novel biomarkers for predicting intrauterine growth restriction: a systematic review and meta-analysis. BJOG: An International Journal of Obstetrics & Gynaecology, 120, 681-694.
Ioannou, C., Talbot, K., Ohuma, E., Sarris, l., Villar, J., Conde-Agudelo, A., & Papageorghiou, A. T. (2012). Systematic review of methodology used in ultrasound studies aimed at creating charts of fetal size. BJOG: An International Journal of Obstetrics & Gynaecology, 119, 1425-1439.
Malone, F. D., Canick, J. A., Ball, R. H., Nyberg, D. A., Comstock, C. H., Bukowski, R., . . . DAlton, M. E., for the First- and Second-Trimester Evalution of Risk (FASTER) Research Consortium. (2005). First-trimester or second-trimester screening, or both, for Downs Syndrome. New England Journal of Medicine, 353(19), 2001-2011.
Sylvan, K., Ryding, E. L., & Rydhstroem, H. (2005). Routine ultrasound screening in the third trimester: A population-based study. Acta Obstetricia et Gynecologica Scandinavica, 84, 1154-1158.
Protocol ID
241501
Variables
Export Variables| Variable Name | Variable ID | Variable Description | dbGaP Mapping | |
|---|---|---|---|---|
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Abdominal_Circumference | ||||
| PX241501060000 | Abdominal circumference (AC): | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Ages_Days | ||||
| PX241501020200 | Gestational Age: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Ages_Weeks | ||||
| PX241501020100 | Gestational Age: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Biometric_Measures | ||||
| PX241501030000 | Biometric measures as they appear on the more | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Biparietal_Diameter | ||||
| PX241501040000 | Bi-parietal diameter (BPD): | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Estimated_Fetal_Weight | ||||
| PX241501080000 | Estimated Fetal Weight (EFW): | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Femur_Length | ||||
| PX241501070000 | Femur length (FL): | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Head_Circumference | ||||
| PX241501050000 | Head circumference (HC): | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Medical_Record_Abstraction | ||||
| PX241501110000 | Estimated Fetal Weight: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Medical_Record_Abstraction_Gestational_Age_Days | ||||
| PX241501100200 | Gestational Age: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Medical_Record_Abstraction_Gestational_Age_Weeks | ||||
| PX241501100100 | Gestational Age: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Medical_Record_Abstraction_Ultrasound_Date | ||||
| PX241501090000 | Date of ultrasound: | N/A | ||
| PX241501_Fetal_Growth_Assessment_Estimated_Weight_Ultrasound_Date | ||||
| PX241501010000 | Date of ultrasound: | N/A | ||
Measure Name
Fetal Growth Assessment - Percentiles for U.S. Populations
Release Date
April 11, 2017
Definition
This measure includes abstraction of fetal growth and ultrasound information from a medical record.
Purpose
Fetal growth is a gestational age-dependent measure of fetal size, measured in grams, in relation to a defined standard growth curve. Fetal growth at both extremes of pathology (Small for gestational age [SGA] and large for gestational age [LGA]) affects fetal/neonatal outcome and has been linked with a variety of comorbidities encountered in later life.
Keywords
pregnancy, gestational age, fetal ultrasound, fetal weight, due date, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health
Measure Protocols
| Protocol ID | Protocol Name |
|---|---|
| 241501 | Fetal Growth Assessment - Percentiles for U.S. Populations |
Publications
There are no publications listed for this protocol.