ajog.org 1 series, elevated HbA1C at the time of screening patients for gestational diabetes mellitus was predictive of macrosomia (>95 percentile) in 50% of patients with gestational diabetes mellitus. HbA1C was measured by cation column chromatography, and the finding of patients with variant hemoglobin was taken into consideration for more accurate interpretation.3 Fong et al1 mentioned that their patient population was predominantly Hispanic; however, these are the very patients who have high likelihood of variant hemoglobin.3 HbA1C, when measured by cation column chromatography, is lower in patients with variant hemoglobin (such as S or C) and higher in those with thalassemia.4 HbA1C values are affected by a number of other factors such as anemia, variant hemoglobin and hypertriglyceridemia, and uremia; thus, these results should be interpreted keeping this information in mind.5,6 Furthermore, HbA1C norms are lower in all trimesters of pregnancy.7 It would be interesting if Fong et al would address this issue of macrosomia (>90th percentile) in their patients with elevated HbA1C level and method of HbA1C measurement in their patients. If there was no macrosomia, then this finding may be attributed to the early diagnosis that resulted in earlier and better glycemic control or that the cut of value of HbA1C used was very low and hence detection of diabetes mellitus was 27%. Unfortunately, no plasma glucose levels were available at the time of initial glycohemoglobin level that was used for screening. Although an attractive proposition, HbA1C for early prediction of gestational diabetes mellitus, should be used with due consideration to various factors enumerated. Laxmi V. Baxi, MD New York University Langone Medical Center New York, NY 10016

Letters to the Editors Columbia University New York, NY [email protected] Margaret Dziadosz, MD New York University Langone Medical Center New York, NY The authors report no conflict of interest. REPLY DECLINED

REFERENCES 1. Fong A, Serra AE, Gabby L, Wing DA, Berkowitz KM. Use of hemoglobin A1c as an early predictor of gestational diabetes mellitus. Am J Obstet Gynecol 2014;211:641-3. 2. Shah BD, Cohen AW, May C. Comparison of glycohemoglobin determination and the one-hour oral glucose screen in the identification of gestational diabetes. Am J Obstet Gynecol 1982;144:774. 3. Baxi LV, Barad D, Reece EA. Use of glycosylated hemoglobin as a screen for macrosomia in gestational diabetes. Obstet Gynecol 1984;64: 347-50. 4. Baxi LV, Reece EA, Barad D, Farber R, William A. Glycosylated hemoglobin (HbA1) and hemoglobinopathies in pregnancy. J Perinat Med 1984;12:133-6. 5. Vikoren TB, Berg JP, Berg TJ. Sources of error when using hemoglobin A1C. Tidsskr Nor Laegeforen 2014;134:417-21. 6. Mostafa SA, Davies MJ, Srinivasan BT, Carey ME, Webb D, Khunti K. Should glycated hemoglobin (HbA1C) be used to detect people with type 2 diabetes mellitus and impaired glucose regulation? Postgrad Med J 2010;86:656-62. 7. Versantvoort AR, Van Roosmalen J, Radder JK. Course of HbA1C in non-diabetic pregnancy related to birth weight. Neth J Med 2013;71: 22-5. ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog. 2015.03.008

Delayed cord clamping? TO THE EDITORS: I congratulate Tarnow-Mordi et al1 on their excellent scientific analysis of delayed cord clamping. I would like to inquire regarding the authors’ views on the terminology itself. The term, delayed, is generally not a good thing and often denotes a maloccurrence. The technique of delayed cord clamping is delayed only when compared with the current common practice, which might best be described as immediate or accelerated. The delay proposed is generally sooner than would occur compared with physiological cord occlusion from vasoconstriction. In that light, I wonder whether the authors would comment on the possibility of using a more accurate and less pejorative term such as semiphysiological cord clamping. -

Jeffrey Wright, MD Atlantic Fetal Medicine Wilmington, NC [email protected] The author reports no conflict of interest.

REFERENCE 1. Tarnow-Mordi, Duley L, Field D, et al. Timing of cord clamping in very preterm infants: more evidence is needed. Am J Obstet Gynecol 2014;211:118-23. ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.ajog. 2015.03.012

Immediate versus delayed cord clamping TO THE EDITORS: I read with interest the Clinical Opinion by Tarnow-Mordi et al entitled “Timing of cord clamping in very preterm infants: more evidence is needed” in the August

2014 issue of the Journal. The authors were quite correct in their comment section that “perinatal medicine is replete with examples of promising interventions, the short-term benefits

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