Fetal exposures For total births (%)
Tobacco exposure 689 ( 10.9 %)
TABLE 1 Total Births - 6343
Opioid exposure 381 ( 6 %)
Microcephalic (< 3 % for gestation ) - 65 - 1.0 % of all births
Cannabis exposure 317 ( 5 %)
Microcephalic with no exposures ( toxic fetal environment , congenital anomaly ) - 32 estimate 0.6 % of unexposed births
Head circumference Z score ± SD
Microcephalic with fetal exposures - 33 *‡ estimate 3.5 % of exposed births
All Tobacco exposures * ( n = 33 )
Tobacco only * ( n = 10 )
Tobacco + Cannabis * ( n = 5 )
Tobacco + opiate * ( n = 12 )
Tobacco + Opiate + Cannabis * ( n = 6 )
-2.44 ± 1.03 -2.54 ± 0.36 -2.39 ± 0.2 -2.18 ± 1.61 -2.85 ± 0.61 -2.53 ± 0.61
SGA (%) 85 % 90 % 80 % 75 % 100 % 66 % Maternal BMI kg / m 2 29.00 ± 7.15 29.83 ± 9.28 30.88 ± 7.00 29.31 ± 5.92 25.09 ± 6.77 31.63 ± 8.42
Total births and total exposures with 65 infants with microcephaly : exposures , head circumference Z scores ( Z score for 3rd percentile = -2.00 ), percentage of infants small for gestation age ( SGA ), and maternal body mass index ( BMI ).
Bivariate correlation analyses demonstrated that tobacco , opioid , and cannabis exposure were all significantly correlated negatively with head circumference percentile at birth (* p < 0.001 ). The greater number of substance exposures also correlated negatively with circumference percentile at birth (‡ p < 0.02 ).
Growth Chart at our institution . At WVU Medicine Children ’ s Hospital , 6,343 infants were born during the review period . Newborn cases were chosen if they were coded for congenital microcephaly or congenital small head [ ICD-9 : 742.1 , ICD-10 : Q02 ]. The diagnosis was identified via the problem list in the electronic medical record ( Epic Systems , Verona , WI ). A single neonatologist was responsible for maintaining the problem lists for all newborns born and admitted to WVU Medicine Children ’ s Hospital newborn services to assure accurate infant data for our Vermont Oxford Data and for noting important comorbidities that may affect proper coding , and billing . As such , we believe the information obtained for this project is accurate . For the babies diagnosed with microcephaly , as well as determining the total number of babies born , the incidence of maternal opioid use , maternal tobacco use ( cigarette smoking ), and maternal cannabis use born at our hospital during the study period , we used Cogito SlicerDicer , which is an Epic built self-service reporting tool with access to key criteria such as ICD-9 and ICD- 10 codes to filter and focus results ( Epic Systems , Verona , WI ).
Charts of infants identified with microcephaly were examined for any combination of in-utero opioid , tobacco , and cannabis exposure . We also reviewed maternal risk factors , including hypertension , preeclampsia , HELLP Syndrome , and maternal viral exposures noted in the infants ’ and mothers ’ charts . We specifically examined whether the infant was tested for cytomegalovirus , as this can be a cause of microcephaly . 12 We also noted whether the infants were intrauterine growth restricted or had any congenital anomalies . For all infants , we calculated Z scores for HC , as well as maternal body mass index ( BMI ) at the time of delivery . This data is detailed in Table 1 .
Tobacco exposure was determined from maternal history . Exposure to opioids and cannabis was determined by the mother ’ s urine drug screen , maternal verbal history , or from umbilical cord or meconium drug screens of the newborn .
STATISTICAL ANALYSES
We examined the normative characteristics of the sample data by first conducting descriptive statistics on all study variables ( means , standard deviations , ranges , frequencies ). We reviewed and discussed any potential outliers in the data prior to comparing the two groups . We also conducted descriptive statistics on outcome variables to identify the prevalence of microcephaly cases that reported conditions such as hypertension , preeclampsia , and HELLP Syndrome . Bivariate correlation analyses were conducted to examine a potential relationship between reported microcephaly and the type and amount of substance exposure reported at birth . A one-way ANOVA was used to compare outcome means ( BMI , Z score , percentage of SGA infants ) based on exposure group . Significance levels were set at p < 0.05 . SPSS Version 26.0 was used to conduct all study analyses .
RESULTS
A breakdown of our findings is detailed in Table 1 . During the review period , 6,343 births occurred . Of the total number of births at the hospital during the study period , 6 % had opioid exposure ( 381 ), 5 % had cannabis exposure ( 317 ), and 11 % had tobacco exposure ( 698 ).
One hundred forty-eight ( 2 % of births during that period ) newborns were coded for congenital microcephaly ( ICD-10 , Q02 and ICD-9 , 742.1 ). Of these 148 infants ,
West Virginia Medical Journal • December 2022 • 33