Influence of maternal asthma and asthma severity on newborn morphometry.
OBJECTIVE
To determine if maternal asthma or asthma severity affects newborn morphometry.


METHODS
A secondary analysis was performed on data collected in a multicenter prospective observational cohort study of asthma in pregnancy. Patients enrolled included women with asthma stratified by severity of disease and controls. Asthma severity was defined according to the classification proposed by the National Asthma Education Program (NAEP) Report of the Working Group on Asthma and Pregnancy, modified to include medication requirements. Newborn morphometry measurements included birth weight (BW) and multiples of the median birth weight (BW-MOM), head circumference (HC), length (L), HC:BW ratio, and ponderal index (PI).


RESULTS
Of 2480 patients there were 828 nonasthmatic controls, 828 with mild, 775 with moderate, and 49 with severe disease. Comparing all groups, there were statistically significant differences in maternal age (p < .001), race (p = .005), parity (p = .006), prepregnancy weight (p = .028), and medical care source (p = .001), with the severe asthma group having the highest mean maternal age (25.7 years), and proportion of African Americans (71.4%), proportion of multiparous patients (63.3%), and proportion of patients receiving government assistance (85.7%). When the control group was excluded from the comparisons, differences in prepregnancy weight and medical care source were no longer significant. BW-MOM and L did not differ between groups. The HC:BW ratio increased with asthma severity (p = .029) and was increased compared to controls (p = .010). This remained significant after controlling for confounding variables (both p <.001). HC was statistically significantly different between all groups (p = .032), as well as among women with varying degrees of asthma severity (p = .013), which was not clinically significant. After covariates adjustment, HC was not significantly different among all groups (p = .228), nor the asthma groups (p = .144).


CONCLUSIONS
Asthma severity is associated with an increased HC:BW ratio. Severity was not found to impact HC, BW-MOM, L, or PI independently. However, the magnitudes of the effects were too small to suggest a clinically significant effect of asthma on neonatal morphometry in this large prospectively studied sample.
Moldenhauer
Julie S
JS
Department of Obstetrics and Gynecology, Wayne State University, Detroit, Michigan, USA. moldenhauerj@email.chop.edu
Lai
Yinglei
Y
Schatz
Michael
M
Wise
Robert
R
Landon
Mark B
MB
Newman
Roger B
RB
Rouse
Dwight J
DJ
Simhan
Hyagriv N
HN
Leveno
Kenneth J
KJ
Miodovnik
Menachem
M
Lindheimer
Marshall D
MD
Wapner
Ronald J
RJ
Varner
Michael W
MW
O'Sullivan
Mary Jo
MJ
Conway
Deborah L
DL
D000293:Adolescent; D000328:Adult; D001249:Asthma / Q000175:diagnosis*; D001724:Birth Weight; D001827:Body Height; D001835:Body Weight; D001837:Body Weights and Measures; D005260:Female; D047109:Fetal Development; D006257:Head / Q000033:anatomy & histology; D006801:Humans; D007231:Infant, Newborn; D007348:Insurance, Health / Q000706:statistics & numerical data; D008423:Maternal Age; D010298:Parity; D011247:Pregnancy; D011248:Pregnancy Complications; D011446:Prospective Studies; D044469:Racial Groups / Q000706:statistics & numerical data; D012907:Smoking / Q000453:epidemiology; D014481:United States; D055815:Young Adult