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Diabetes, with a prevalence rate of 10-30% in pregnancy, is one of the major causes of intrauterine growth defects and congenital anomalies (1, 2). Various studies have indicated that the risk of fetal anomalies in diabetic mothers is 4-5 times higher than non-diabetic mothers (3, 4). These anomalies can be divided into two categories, namely cardiac and non-cardiac diseases (5, 6). Non-cardiac diseases include cerebral, renal, gastrointestinal, and vascular diseases. According to previous studies, heart diseases account for most of the birth disorders (6).
Based on the statistics, the incidence rate of congenital heart diseases in the normal population is 0.39-0.39% (4), while this rate is 2.8-21% in infants of diabetic mothers (7, 8). Furthermore, it should be mentioned that the most common heart diseases caused by maternal diabetes include PDA, HCM, VSD, ASD, TGA, LVH, PFO, MR, TR, AI, COA, Tetralogy of Fallot, and cardiomegaly (9, 10). Among such diseases, interventricular septal hypertrophy resolves over time (11-15); however, some of them might require intensive care and sometimes medical-surgical interventions. Therefore, there is a need for early detection of such cases and the determination of a method for screening these disorders in high-risk patients (7, 12).
Congenital anomalies are the most important cause of fetal death in diabetic neonates (4), therefore, it is necessary to determine a screening method for them. Echocardiography is increasingly used as a non-invasive method for examining the functional and structural characteristics of the heart. However, it has not yet received much attention in our country as a suitable tool for screening heart diseases. Nevertheless, with the increasing use of these diagnostic tools in our country, further investigations are needed to determine its value as a diagnostic and screening tool. The present study aimed to investigate the types of congenital heart disorders in neonates of diabetic mothers who referred to or were hospitalized in teaching hospitals of Qom, Iran.
  
Materials and Methods
This cross-sectional study was performed on neonates of diabetic mothers who referred to or were hospitalized in Hazrat Masoumeh Hospital, Qom, Iran. The required sample size for this study was estimated at 200 subjects, by using the sample size formula and based on 5% Type I error, 9% accuracy, and a frequency rate of 50% echocardiographic abnormalities in the diabetic mothers, based on the results of similar studies. Moreover, the participants were selected using the convenience sampling method and were investigated for congenital heart disorders. Furthermore, the inclusion criteria consisted of having mothers who use drugs, such as anticonvulsants, lithium, and warfarin.
On the other hand, the exclusion criteria consisted of 1) alcohol abuse of mothers, 2) infliction of mothers with diseases, such as hypertension, thyroid disorders, and lupus, and 3) infliction of neonates with genetic diseases, such as Down and Turner syndromes. The instrument used in this study was a checklist, which included variables, such as the maternal age, gestational age, gender of the infant, occupation of the mother, family history, maternal blood glucose, Apgar score, respiratory distress, cyanosis, and echocardiographic results. These checklists were completed when the participants visited the hospital for neonatal cardiography and in collaboration with the mothers. Regarding the ethical considerations, all the families were told that the information will be kept confidential. After the collection of the questionnaires, the data were analyzed in SPSS software (version 20) using independent t-test, chi-squared, and Fisher tests. Moreover, the mean and standard deviation were calculated for quantitative variables while frequency and percentage were calculated for qualitative variables. A p-value of 0.05 was considered statistically significant for all the tests.
 
Results
For the purposes of the study, 200 patients were studied (72% [n=144] male and 28% [n=56] female). In total, 8%, 44%, and 48% of the participants weighed >2500 gr, 2500-4000 gr, and <4000 gr, respectively. Moreover, the birth of 192 neonates (96%) was term while 8 neonates (4%) were born preterm. Furthermore, the age of 52%, 36%, and 12% of mothers were 20-30, 30-40, and <40 years. In addition, 76% of the mothers had occupations outside of their houses. In total, 56% (n=112) and 44% (n=88) of the mothers were inflicted with gestational diabetes mellitus and overt diabetes. Moreover, 25% (n=50) and 19% (n=38) of the subjects were diagnosed with type 1 and type 2 diabetes. In the present study, 8% (n=16) of neonates had a family history of congenital heart disease and 76% (n=152) of the parents were cousins. It should be mentioned that 72% of the deliveries were Cesarean section while the rest were normal vaginal delivery. Birth Apgar scores in 4% and 96% of the participants were 4-7% and 8-9%, respectively.
In this study, the echocardiographic results were abnormal in 49% (n=82) of the participants which are shown in Table 1.
 
Table 1. Echocardiographic results of diabetic mothers

Variable	Result	Frequency	Percent
PFO	POS	139	69.5
	NEG	61	30.5
PDA	POS	82	41
	NEG	118	59
ASD	POS	3	1.5
	NEG	197	98.5
VSD	POS	6	3
	NEG	194	97
TR	POS	7	3.5
	NEG	193	96.5
MR	POS	0	0
	NEG	200	100
CHD	POS	0	0
	NEG	200	100

 
 

 
 
 
 
Table 2. Relationship between demographic planners and echocardiographic evaluation

			Gestational age			Gender			Occupation of Mothers			Residence			Blood Relationship between parents			Family history
			Term	Pre-term	Male		Female	Clerk		Housewife	Urban		Rural	Cousins		Non-cousins	Yes		No
Echo	Normal		80	38	62		56	2		116	110		8	86		32	1		117
	Abnormal		20	62	53		29	3		79	5		77	55		27	80		2
p-value		0.000				0.089			0.382			0.847			0.377			0.749