The Hadlock Method Is Superior to Newer Methods for the Prediction of the Birth Weight Percentile.

OBJECTIVES: To compare a traditional ultrasound (US) method for estimated fetal weight (EFW) calculation and fetal growth restriction diagnosis with 2 newer methods for the prediction of small for gestational age (SGA) at birth. METHODS: We reviewed deliveries at our institution from January 1, 2013, to March 31, 2017. Singleton, nonanomalous, well-dated fetuses with a US examination within 2 weeks of delivery were included. Estimated fetal weights and percentiles were calculated by a traditional method (Hadlock et al; Radiology 1991; 181:129-133) and 2 newer methods: Intergrowth-21st (INTG; Ultrasound Obstet Gynecol 2017; 49:478-486) and Salomon et al (Ultrasound Obstet Gynecol 2007; 29:550-555). We calculated each method's test characteristics to predict SGA (birth weight < 10th percentile) using both traditional (EFW < 10th percentile) and receiver operating characteristic (ROC)-derived fetal growth restriction cutoffs. Mean percentile discrepancies between EFW and birth weight measurements were calculated to compare method accuracy. We hypothesized that the INTG and Salomon methods would have superior SGA prediction compared with the Hadlock method. RESULTS: Of 831 pregnancies with a US examination within 2 weeks of delivery, 138 (16.7%) were SGA at birth. Hadlock had the smallest US-birth weight percentile discrepancy (P < .001 versus both INTG and Salomon). When comparing ROC curves, the Hadlock and INTG methods performed comparably, with areas under the curve of 0.91 and 0.90 (P = .08) and optimal EFW cutoffs of the 15th and 22nd percentiles, respectively. The Salomon method performed less well, with an area under the curve of 0.82 (P < .001 versus both Hadlock and INTG methods). CONCLUSIONS: In our study cohort, the Hadlock method predicted the birth weight percentile more accurately than the INTG or Salomon methods and performed comparably with INTG to predict SGA when ROC-derived cutoffs were used.

Comparing the Hadlock fetal growth standard to the Eunice Kennedy Shriver National Institute of Child Health and Human Development racial/ethnic standard for the prediction of neonatal morbidity and small for gestational age.

BACKGROUND: The fetal growth standard in widest use was published by Hadlock >25 years ago and was derived from a small, homogeneous cohort. In 2015, The Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Study published updated standards that are specific to race/ethnicity. These do not allow for precise estimated fetal weight percentile calculation, however, and their effectiveness to predict neonatal morbidity and small for gestational age has not yet been compared to the long-standing Hadlock standard. OBJECTIVE: We compared the ability of the Hadlock standard to predict neonatal morbidity and small for gestational age at birth with that of The Eunice Kennedy Shriver National Institute of Child Health and Human Development race-/ethnicity-specific standard. Our secondary objective was to compare their performance among our Native American population, which is not accounted for in the Eunice Kennedy Shriver National Institute of Child Health and Human Development standard. STUDY DESIGN: For this retrospective study of diagnostic accuracy, we reviewed deliveries at the University of New Mexico Hospital from Jan. 1, 2013, through March 31, 2017. We included mothers with singleton, well-dated pregnancies and nonanomalous fetuses with an estimated fetal weight within 30 days of delivery. Cubic spline interpolation was performed on the Eunice Kennedy Shriver National Institute of Child Health and Human Development estimated fetal weight-percentile tables to calculate percentiles specific to the gestational day. Estimated fetal weight percentiles were then calculated using both the Hadlock and Eunice Kennedy Shriver National Institute of Child Health and Human Development race-/ethnicity-specific standards according to maternal self-identified race/ethnicity. We calculated the receiver operator area under the curve of each method to predict composite and severe composite neonatal morbidity and small for gestational age at birth (birthweight <10th percentile). As an additional measure of method accuracy, we calculated the mean ultrasound-birthweight percentile discrepancy. For Native Americans, percentiles were calculated using the Hadlock and Eunice Kennedy Shriver National Institute of Child Health and Human Development race/ethnicity standards (white, black, Hispanic, Asian), and test characteristics were calculated for each to predict neonatal morbidity and small for gestational age. RESULTS: We included 1514 women, with a mean ultrasonography-to-delivery interval of 14.4 days (±8.8) and a small for gestational age rate of 13.6% (n = 206). For the prediction of both composite and severe composite neonatal morbidity, the Hadlock method had superior performance, with higher areas under the curve than the Eunice Kennedy Shriver National Institute of Child Health and Human Development method (P < .001 for both), though neither had good discriminatory value (all areas under the curve <0.8). For the prediction of small for gestational age at birth, the Hadlock standard had higher sensitivity (61.1%) than the Eunice Kennedy Shriver National Institute of Child Health and Human Development standard, both when using the interpolated Eunice Kennedy Shriver National Institute of Child Health and Human Development method (36.2%, P < .01) and the Eunice Kennedy Shriver National Institute of Child Health and Human Development whole-week 10th percentile cutoff (46.7%, P < .01). The Hadlock method also had a higher area under the curve than the Eunice Kennedy Shriver National Institute of Child Health and Human Development interpolated method to predict small for gestational age (0.89 vs 0.88, P < .01). The Hadlock method had a lower ultrasound-birthweight percentile discrepancy than the Eunice Kennedy Shriver National Institute of Child Health and Human Development method (6.1 vs 16.5 percentile points, P < .01). Fetuses classified as growth restricted by Hadlock but not Eunice Kennedy Shriver National Institute of Child Health and Human Development had significantly higher composite morbidity than normally grown fetuses. Among Native American women, the Hadlock method had the highest area under the curve to predict composite and severe composite morbidity, while the Hadlock and all Eunice Kennedy Shriver National Institute of Child Health and Human Development race-/ethnicity-specific methods performed comparably to predict small for gestational age. CONCLUSION: Despite its publication >25 years ago, the Hadlock standard is superior to the Eunice Kennedy Shriver National Institute of Child Health and Human Development race-/ethnicity-specific standard for the prediction of both neonatal morbidity and small for gestational age.

Effect of ibuprofen vs acetaminophen on postpartum hypertension in preeclampsia with severe features: a double-masked, randomized controlled trial.

BACKGROUND: Nonsteroidal antiinflammatory drug use has been shown to increase blood pressure in nonpregnant adults. Because of this, the American College of Obstetricians and Gynecologists suggests avoiding their use in women with postpartum hypertension; however, evidence to support this recommendation is lacking. OBJECTIVE: Our goal was to test the hypothesis that nonsteroidal antiinflammatory drugs, such as ibuprofen, adversely affect postpartum blood pressure control in women with preeclampsia with severe features. STUDY DESIGN: At delivery, we randomized women with preeclampsia with severe features to receive around-the-clock oral dosing with either 600 mg of ibuprofen or 650 mg of acetaminophen every 6 hours. Dosing began within 6 hours after delivery and continued until discharge, with opioid analgesics available as needed for breakthrough pain. Study drugs were encapsulated in identical capsules such that patients, nurses, and physicians were masked to study allocation. Exclusion criteria were serum aspartate aminotransferase or alanine aminotransferase >200 mg/dL, serum creatinine >1.0 mg/dL, infectious hepatitis, gastroesophageal reflux disease, age <18 years, or current incarceration. Our primary outcome was the duration of severe-range hypertension, defined as the time (in hours) from delivery to the last blood pressure ≥160/110 mm Hg. Secondary outcomes were time from delivery to last blood pressure ≥150/100 mm Hg, mean arterial pressure, need for antihypertensive medication at discharge, prolongation of hospital stay for blood pressure control, postpartum use of short-acting antihypertensives for acute blood pressure control, and opioid use for breakthrough pain. We analyzed all outcome data according to intention-to-treat principles. RESULTS: We assessed 154 women for eligibility, of whom 100 met entry criteria, agreed to participate, and were randomized to receive postpartum ibuprofen or acetaminophen for first-line pain control. Seven patients crossed over or did not receive their allocated study drug, and 93 completed the study protocol in their assigned groups. We found no differences in baseline characteristics between groups, including mode of delivery, body mass index, parity, race, chronic hypertension, and maximum blood pressure prior to delivery. We did not find a difference in the duration of severe-range hypertension in the ibuprofen vs acetaminophen groups (35.3 vs 38.0 hours, P = .30). There were no differences between groups in the secondary outcome measures of time from delivery to last blood pressure ≥150/100 mm Hg, postpartum mean arterial pressure, maximum postpartum systolic or diastolic blood pressures, any postpartum blood pressure ≥160/110 mm Hg, short-acting antihypertensive use for acute blood pressure control, length of postpartum stay, need to extend postpartum stay for blood pressure control, antihypertensive use at discharge, or opioid use for inadequate pain control. In a subgroup analysis of patients who experienced severe-range hypertension, the mean time to blood pressure control in the acetaminophen group was 68.4 hours and ibuprofen group was 56.7 hours (P = .26). At 6 weeks postpartum, there were no differences between groups in the rates of obstetric triage visits, hospital readmissions, continued opioid use, or continued antihypertensive use. CONCLUSION: The first-line use of ibuprofen rather than acetaminophen for postpartum pain did not lengthen the duration of severe-range hypertension in women with preeclampsia with severe features.

A Comparison of Methods for the Diagnosis of Fetal Growth Restriction Between the Royal College of Obstetricians and Gynaecologists and the American College of Obstetricians and Gynecologists.

OBJECTIVE: The Royal College of Obstetricians and Gynaecologists (RCOG) defines fetal growth restriction as ultrasound-estimated fetal weight less than the 10th percentile or abdominal circumference less than the 10th percentile; the American College of Obstetricians and Gynecologists (ACOG) defines fetal growth restriction as estimated fetal weight less than the 10th percentile alone. We compared each method's ability to predict small for gestational age (SGA) at birth. METHODS: For this retrospective study of diagnostic accuracy, we reviewed deliveries at the University of New Mexico Hospital from January 1, 2013, to March 31, 2017. We included mothers with singleton, well-dated pregnancies and nonanomalous fetuses undergoing indicated fetal growth restriction surveillance with an ultrasound-estimated fetal weight within 30 days of delivery. Estimated fetal weights and percentiles were calculated using the Hadlock intrauterine growth curve. Small for gestational age was defined as birth weight less than the 10th percentile based on a recent, sex-specific curve. We calculated the area under the curve, sensitivity, specificity, and positive and negative likelihood ratios for various approaches using abdominal circumference and estimated fetal weight to diagnose fetal growth restriction, including the definitions endorsed by ACOG and RCOG. RESULTS: We included 1,704 pregnancies with a mean ultrasonography-to-delivery interval of 14.0 days (±8.6). There were 235 SGA neonates (13.8%). The rate of fetal growth restriction was 13.6% when using ACOG's criteria and 16.9% according to RCOG's criteria (P=.007). The area under the curve of RCOG's diagnostic approach was 0.78 (95% CI 0.76-0.80), which was higher than ACOG's (0.76, 95% CI 0.74-0.78, P=.01). Sensitivities and specificities of the various methods were similar. Adopting estimated fetal weight or abdominal circumference less than the 10th percentile instead of estimated fetal weight alone to predict SGA at birth would correctly identify one additional case of SGA for each 14 patients assessed. CONCLUSION: The diagnostic approach endorsed by RCOG is a marginally better predictor of SGA at birth compared with the method endorsed by ACOG. Future research should consider the potential benefits and harms of the different methods in different populations.