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Journal of Human Nutrition and Food Science

Relationship between Different Iodine Status during Pregnancy and Infantile Physical Development in China

Research Article | Open Access Issue 2333-6706
Article DOI :

  • 1. Department of Nutrition and Food Hygiene, Tianjin Medical University, China
  • 2. Department of Epidemiology and Biostatistics, Guangdong Medical University, China
  • 3. Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, China
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Corresponding Authors
Wanqi Zhang, Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin 300070, China, Tel: 011-86-22-8333-6595; Fax: 011-86-22-8333-6603
INTRODUCTION

Iodine is an essential microelement to maintain human health [1, 2]. Especially, during the first 1,000 days of life, adequate iodine intake is unequivocally important for infantile physical and brain development [3]. The iodine requirement increases during pregnancy due to the transfer of iodine to the fetus and increased maternal thyroid hormone synthesis [4]. Therefore, pregnant women are highly vulnerable to iodine deficiency.

Approximately 90% of the iodine ingested by the body is excreted in the urine, so urine iodine is a good indicator of recent iodine intake. Median urinary iodine excretion is a recommended biomarker for monitoring daily iodine intake in specific populations [5,6]. World Health Organization (WHO)/ United Nations International Children’s Emergency Fund (UNICEF)/ International Council for Control of Iodine Deficiency Disorders (ICCIDD) recommended an adequate median urine iodine concentration (UIC) of 150 249μg/L for pregnant women, higher than that for reproductive women (100-199μg/L) [7]. The latest national iodine deficiency disease surveillance reported that the iodine status of residents in China was appropriate. But in six provinces and cities, the median UIC for pregnant women was lower than 150μg/L, indicating mild iodine deficiency [8].

Iodine deficiency during lactation will affect the iodine nutritional status and thyroid function of infants, and even negatively affect their growth and development [9]. But, evidence on the effects of iodine status during pregnancy on infantile growth and development is limited. Severe iodine deficiency during pregnancy can lead to a series of adverse pregnancy outcomes, including thyroid dysfunction, miscarriage, and stillbirth, even congenital cretinism and growth retardation in infants [3,10]. However, current research on the relationship between mild iodine deficiency in pregnancy and physical development is inconclusive. Some studies reported adverse effects of mild iodine deficiency during pregnancy on infantile growth and development [11,12]. However, results from other cohort studies have shown no differences in infantile physical development between mothers with mild iodine deficiency [9,13].

Due to the success of salt iodization programmer commonly implemented in China, public health attention has shifted to mildto-moderate iodine deficiency, which is still prevalent in some areas, especially among pregnant women. Currently, there are few and controversial studies on the relationship between iodine status during pregnancy and physical development. This study was aimed to investigate physical development of infants at 18- 24 months old under different maternal iodine status during pregnancy and evaluate the relationship between iodine status during pregnancy and physical development of infants in China. This prospective study compared different maternal iodine levels in relation to infant physical development.

MATERIALS AND METHODS

Subjects and Design

This study is a part of an ongoing prospective study conducted in Tianjin and Wuqiang, which was designed to explore the relationship between iodine status during pregnancy and neonatal Thyroid stimulating hormone (TSH) and infants’ physical growth at 18-24 months old. These two areas are adjacent, with similar geography, culture, dietary habits, and food and water iodine concentration. Wuqiang is a county in Hebei Province, where the iodine content in drinking water is <15.0μg/L and both crude salt (non-iodized) and refined iodized salt are consumed. In a pilot study among 77 pregnant women in Wuqiang the 24-h UIC was 108 (69, 163) μg/L, and 67.6% of the UIC values were <150μg/L. Therefore, ?Wuqiang was chosen as a mildly iodine-deficient region for this study. Tianjin, where iodized salt is the main source of iodine, is iodine sufficient (8).

All subjects were recruited from the Departments of Obstetrics in ?Tanggu Maternity Hospital, Tianjin and the Wuqiang Center of Diseases Prevention and Control, Hebei from March 2016 to June 2018. All pregnant women presenting for their routine antenatal care during pregnancy were invited to participate in our study after a general description of the project. The gestational week was determined based on the results of the ultrasound examination of the pregnant woman’s abdomen or the time of the last menstruation. Women aged 20-35 years with no previous history of thyroid disease, no use of thyroidrelated medications, and no other chronic diseases were eligible for inclusion. Pregnant women who had lived in the local area for less than 5 years or who were using iodine supplements were excluded. Pregnant women were recalled back 18-24 months after delivery and were investigated, until to December 2019, 469 mother-infant pairs were recruited. All research protocols were approved by the Medical Ethics Committee of Tianjin Medical University, all procedures performed in the study were in accordance with the ethical standards of the committee and with the 1964 Helsinki declaration. All participants provided written informed consent after research protocols were carefully explained to them (Ethical approval number: NCT03710148).

Data and Sample collection

Subjects during pregnancy were asked to complete a questionnaire to obtain information including age, gestational week, height and weight, etc. Maternal spot urine was obtained at enrollment from 8:00 to 11:00 AM after an overnight fast during an antenatal hospital visit. Dried blood spot samples were obtained from neonatal heels and infantile fingertips at birth and 18-24 months old, respectively. Infantile length and weight were measured at birth and 18-24 months old, and head and bust circumstance were measured only at 18-24 months old. Z-scores were calculated by (X-M)/S, M represents Reference standard median by WHO, S represents standard deviation, the physical growth of infants was categorized based on criteria of Z-scores recommended by WHO, <-2 is extremely delayed, <-1 is moderately delayed, <0 is slightly delayed, >0 is above the normal level, >1 is well developed, >2 is extremely developed. All samples were frozen at -80°C for assay within 2 weeks.

Analysis of urine samples & Categorization of UIC

UIC was analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS, Thermo Fisher Scientific iCAPTMQ, Germany) in the Tianjin Key Laboratory of Environmental Nutrition and Population Health. Based on the distribution of maternal UIC and WHO criteria, pregnant women were divided into 4 groups: <100μg/L (moderate deficiency), 100-149μg/L (mild deficiency), 150-249μg/L (sufficiency), >250μg/L (above requirements) in this study.

Determination of heel/fingertip TSH

Infants’ heel/fingertip blood spot samples were collected on filter papers by skilled nurses at 72 hours after birth. All the samples were sent to the Tianjin Maternal and Child Health Center for analysis. Dried blood spot TSH was measured using dissociation-enhanced fluor-immunoassay.

Statistical analysis

All statistical analyses were performed using SPSS25.0 (IBM, Inc., New York, NY, USA), and Microsoft Excel (Win10 2016). The
Kolmogorov-Smirnov method was used to test data distribution normality. Normally distributed data were presented as mean ± SD, and skewed data are presented as median (interquartile range). Difference in basic information between boys and girls was analyzed by t test or Kruskal-Wallis test. Difference in Z-scores, fingertip TSH and UIC of infants were analyzed via oneway ANOVA or nonparametric test. Significance was set at P<0.05 (two-tailed).

RESULTS

Demographic characteristic of infants at 18-24 months

Totally, 469 mother-infant pairs were enrolled in this study. The UIC of mother during pregnancy were 161 (111, 251) μg/L, indicating adequate iodine nutrition according to the WHOrecommended criteria of the UIC in pregnant women (data not shown). The basic information of their neonates was described in Table 1. Birth weight in female neonates was lower than that in male neonates (P=0.001), and the length-for-age (LFA) and weight-for-length (WFL) Z-scores were lower than those in male neonates (P<0.05). The median TSH levels of neonates were 3.1 (1.7, 4.5) mIU/L, no difference was found between boys and girls.

Pregnant women were recalled back 18-24 months after delivery, the average age of infants was 20.9 ± 3.0 months. Present weight, head circumference and bust in girls were lower than boys (P<0.001), no difference in gender of present length was found (P=0.231), and the corresponding WFL Z-scores in girls was also lower, while the LFA Z-scores in girls was higher than boys (P=0.007), differed from the trend of present length. The UIC in infants at 18-24 months was 217 (121, 361) μg/L, indicating adequate iodine nutrition. Both UIC and fingertip TSH in infants were not found difference between boys and girls (P>0.05).

UIC-specific difference of physical growth of infants

Based on the WHO-recommended criteria of the UIC during pregnancy, maternal UIC were divided into 4 groups (Table 2). No difference in birth length, weight, LFA Z-scores, weight-for-age (WFA) Z-scores and WFL Z-scores in neonates was found among different maternal UIC groups (all P>0.05). At 18-24 months after delivery, similar trends were found. Only head-for-age (HFA) Z-scores in UIC within 100-149μg/L during pregnancy was above 0, and it was highest (P=0.010), rather than 150-249μg/L, which
was recommended by WHO as the criteria of sufficient iodine nutrition during pregnancy (Figure 1).

Both heel-blood and fingertip TSH showed no differences among different UIC groups (P>0.05). Weak but no significant difference in UIC in infants at 18-24 months was found (P=0.661).

Difference of physical growth in infants with different neonatal TSH

No infants were diagnosed as congenital hypothyroidism. Take 4.0mIU/L as the cut-off point, neonatal TSH was divided into 2 groups (Table 3). Compared to neonates with TSH<4.0mIU/L, no difference of birth length, weight, LFA Z-scores, WFA Z-scores
and WFL Z-scores was found in neonates with TSH ≥4.0mIU/L (all P>0.05). At the age of 18-24 months, no significant changes also was found in length, weight, head circumference and bust in infants. LFA Z-scores in infants with neonatal TSH<4.0mIU/L was significantly higher than that in infants with neonatal TSH ≥4.0mIU/L (P=0.006), while no difference was found in WFA Z-scores, WFL Z-scores and HFA Z-scores between infants with neonatal TSH <4.0mIU/L and ≥4.0mIU/L (all P>0.05).

High neonatal TSH followed high fingertip TSH in infants at the age of 18-24 months (P<0.001), although fingertip TSH was within normal ranges. While, no impact was found in infants with neonatal TSH ≥4.0mIU/L on UIC in infants at 18-24 months was found (P=0.864).

DISCUSSION

Adequate iodine intake during pregnancy is vitally important to maintain the health of themselves and their offspring. A little much is too much, especially the iodine intake during pregnancy. Abnormal iodine nutrition during pregnancy has an adverse effect on the thyroid function of pregnant women and the brain development and physical growth of their infants [14,15]. UIC is most frequently used to evaluate the iodine nutrition of pregnant women and related criteria are defined by WHO/UNICEF/ ICCIDD. The UIC during pregnancy in the present study was 161 (111, 251) μg/L, suggesting sufficient iodine nutrition, which was consistent with previous study in Tianjin (16). While part of iodine-deficient pregnant women still exists. The effect of iodine deficiency during pregnancy on physical growth lacked concern evidence, a few studies reported negative effect [15,17], but no effects were also reported [18]. Our study aimed to evaluate the effect of iodine nutrition during pregnancy on physical growth of infants.

Boys’ physical and psychological development is earlier than girls’ at the same age [19-21] which was also shown in our study, especially in LFA Z-scores at 18-24 months, although no difference at birth. A Britain study showed no difference in infantile birth weight and length with various UIC levels during pregnancy [22], even in infants whose mothers were diagnosed with subclinical hypothyroidism or hypothyroidism [18,23]. Similar results were found in our study. While in other studies, for example, in Spain [24], a mildly iodine deficient country, compared with infants with maternal UIC <50μg/L, infantile weight was 189g heavier when their mothers’ UIC was within 100-150μg/L. Another study conducted in Wuhan, China, reported that when pregnant women had a UI/Creatinine higher than 500μg/g, their infantile weight birth weight was lighter than those infants with sufficient iodine nutrition (2833 vs 3007g) [25]. Serve iodine deficiency can result in cretinism, a series of irreversible and adverse outcomes of infantile development and growth. Restricted physical growth, as the most obvious symptom of cretinism, affects the entire life cycle of infants [26]. At 18-24 months after delivery, significance was only found in infantile HFA Z-scores among different maternal UIC levels during pregnancy. Only when the maternal UIC was within 100-149μg/L during pregnancy, the HFA Z-scores in infants was above zero, which may impact infantile intelligence, because the head circumference of infants was reported to be related to the distant brain development.

Congenital hypothyroidism can cause delayed psychological and physical development of infants, as well as children. No infants at birth were diagnosed as congenital hypothyroidism in our study due to the iodine nutrition in these areas being a mild-to-moderate deficiency, it’s not iodine deficient enough during pregnancy to lead to congenital hypothyroidism in their infants. LFA Z-scores in infants with heel-blood TSH <4.0mIU/L were higher than that with heel-blood TSH ≥4.0mIU/L. Neonatal TSH was reported to be positively related to maternal TSH during pregnancy [27], which correlated with their iodine nutrition. What’s more, higher neonatal TSH is followed with high TSH in children at 18-24 months, while this effects on their distant development is still uncertain. So more and deep studies are needed to confirm the influence of mild-to-moderate iodine deficiency during pregnancy on themselves and their infantile health.

In conclusion, even if the iodine nutrition during pregnancy was mildly deficient, it may affect their infantile physical development, especially the head circumference, which is related to brain development distantly. Further studies need to be conducted to clarify the effects of mild iodine deficiency during pregnancy on their infants. Surveillance should be continued on pregnant women all around the country.

There are limitations to our study. Firstly, our study only analyzed the effect of iodine-related factors during pregnancy, but other micronutrients were not included. Second, pregnant women and neonates recruited in this study were free of thyroid disease, which may lead to the neglect of some pregnant women who are susceptible to thyroid disease.

Table 1: describes the basic information of 469 newborns

 

Total (N=469)

Boys (n=245)

Girls (n=224)

P

Birth length, cm

51.1 ± 1.8

51.2 ± 2.0

50.9 ± 1.7

0.079

Birth weight, kg

3.4 ± 0.4

3.5 ± 4.4

3.3 ± 4.4

0.001

Birth LFA Z-scores

0.81 ± 0.97

0.68 ±1.03

0.95 ± 0.88

0.003

Birth WFA Z-scores

0.33 ± 0.99

0.33 ± 0.88

0.34 ± 1.09

0.968

Birth WFL Z-scores

−0.58 ± 1.05

−0.39 ± 1.13

−0.80 ± 0.91

<0.001

Neonatal TSH, mIU/L

3.1 (1.7, 4.5)

3.1 (1.8, 4.4)

3.0 (1.7, 4.5)

0.788

Age, months

20.9 ± 3.0

20.8 ± 2.9

21.0 ± 3.0

0.498

Present length, cm

85.2 ± 4.1

85.4 ± 4.2

84.9 ± 4.1

0.231

Present weight, kg

11.9 ± 1.5

12.2 ± 1.6

11.6 ±1.3

<0.001

Head, cm

47.2 ± 1.6

47.6 ± 1.6

46.8 ± 1.5

<0.001

Bust, cm

49.4 ± 2.8

49.9 ± 2.9

48.8 ±2.5

<0.001

LFA Z-scores

0.34 ± 1.12

0.20 ± 1.23

0.48 ± 0.97

0.007

WFA Z-scores

0.53 ± 1.03

0.53 ±1.15

0.53 ± 0.89

0.995

WFL Z-scores

0.48 ± 1.14

0.60 ±1.25

0.35 ± 1.00

0.018

HFA Z-scores

−0.17 ± 1.13

−0.26 ± 1.20

0.03 ± 1.04

0.064

Fingertip TSH, mIU/L

1.4 (0.9, 1.9)

1.4 (0.9, 2.0)

1.4 (0.9, 1.9)

0.778

UIC, μg/L

217 (121, 361)

241 (128, 374)

191 (114, 325)

0.121

Data were expressed as Mean ± SD or Median (P25, P75).

TSH, thyroid stimulating hormone; UIC, urinary iodine concentration; LFA, length-

for-age; WFA, weight-for-age; WFL, weight-for-length; HFA, head-for-age.

Table 2: describes the physical development of newborns with different urinary iodine levels.

 

UIC during pregnancy, μg/L

 

P

 

<100

100-149

150-249

≥250

Birth length, cm

51.3 ± 1.7

51.0 ± 2.0

51.1 ± 2.0

50.7 ± 1.9

0.383

Birth weight, kg

3.5 ± 0.4

3.4 ± 0.5

3.4 ± 0.5

3.3 ± .04

0.386

Birth LFA Z-scores

0.89 ± 0.88

0.81 ± 1.08

0.82 ± 1.04

0.65 ± 1.02

0.514

Birth WFA Z-scores

0.46 ± 0.88

0.35 ± 1.10

0.24 ± 1.10

0.23 ± 0.93

0.475

Birth WFL Z-scores

−0.46 ± 0.98

−0.56 ± 1.13

−0.75 ± 1.10

−0.54 ± 1.07

0.355

Neonatal TSH, mIU/L

3.7 (2.0, 4.9)

2.6 (1.6, 4.0)

3.1 (1.7, 4.7)

3.5 (1.7, 4.5)

0.195

Present length, cm

85.8 ± 4.6

85.0 ± 4.3

84.5 ± 3.7

84.9 ± 3.9

0.291

Present weight, kg

12.1 ± 1.6

11.9 ± 1.6

11.7 ± 1.3

11.7 ± 1.4

0.411

Head, cm

47.0 ± 1.7

47.5 ± 1.7

47.2 ± 1.5

46.9 ± 1.4

0.098

Bust, cm

49.3 ± 2.9

49.3 ± 2.5

49.3 ± 2.6

49.3 ± 2.9

0.999

LFA Z-scores

0.26 ± 1.14

0.41 ± 1.29

0.18 ± 0.97

0.38 ± 1.19

0.526

WFA Z-scores

0.47 ± 1.04

0.63 ± 1.13

0.45 ± 0.89

0.49 ± 1.02

0.652

WFL Z-scores

0.46 ± 1.1

0.56 ± 1.29

0.48 ± 0.99

0.39 ± 1.2

0.818

HFA Z-scores

−0.33 ± 1.19

0.23 ± 1.13

−0.06 ± 1.07

−0.23 ± 1.03

0.010

Fingertip TSH, mIU/L

1.3 (0.8, 2.2)

1.4 (0.9, 2.1)

1.3 (0.8, 1.8)

1.4 (1.0, 1.9)

0.770

UIC, μg/L

200 (115, 374)

215 (99, 389)

238 (140, 343)

252 (159, 388)

0.661

<100

14 (22.6%)

18 (25.7%)

16 (17.8%)

11 (15.3%)

0.398

Data were expressed as Mean ± SD or Median (P25, P75) or n (%).

UIC, urinary iodine concentration; TSH, thyroid stimulating hormone; LFA, length-for-age; WFA, weight-for-age; WFL, weight-for-length; HFA, head-for-age.

 

 

Table 3: describes the effects of different neonatal TSH levels on children's physical development.

 

Neonatal TSH, mIU/L

 

P

<4.0

≥4.0

Birth length, cm

51.3 ± 1.9

51.3 ± 1.7

0.951

Birth weight, kg

3.4 ± 0.5

3.4 ± 0.4

0.259

Birth LFA Z-scores

0.95 ± 0.99

0.96 ± 0.91

0.934

Birth WFA Z-scores

0.41 ± 1.01

0.29 ± 0.95

0.275

Birth WFL Z-scores

−0.67 ± 0.90

−0.85 ± 0.86

0.082

Present length, cm

85.5 ± 4.1

84.7 ± 4.2

0.094

Present weight, kg

12.0 ± 1.6

11.8 ± 1.4

0.517

head (cm)

47.4 ± 1.6

47.0 ± 1.6

0.086

Bust (cm)

49.7 ± 2.9

49.6 ± 2.6

0.702

LFA Z-scores

0.51 ± 1.1

0.17 ± 1.04

0.006

WFA Z-scores

0.6 ± 1.12

0.48 ± 0.89

0.305

WFL Z-scores

0.45 ± 1.24

0.52 ± 0.96

0.595

HFA Z-scores

0.07 ± 1.1

−0.17 ± 1.19

0.066

Fingertip TSH, mIU/L

1.2 (0.8, 1.7)

1.8 (1.4, 2.3)

<0.001

UIC, μg/L

230 (130, 366)

241 (127, 366)

0.864

Data were expressed as Mean ± SD or Median (P25, P75).

TSH, thyroid stimulating hormone; LFA, length-for-age; WFA, weight-for-age; WFL,

weight-for-length; HFA, head-for-age; UIC, urinary iodine concentration.

FUNDING

This work was supported by ?the ?National Natural Science Foundation of China (No. 81920108031, ?82230113 and 81330064).

ACKNOWLEDGEMENTS

We gratefully acknowledge all the participants in this study, along with Tianjin Maternal and Child Health Hospital, for their assistance in thyroid function measurements.

AUTHOR CONTRIBUTIONS

Wanqi Zhang conceived the study. Wen Wu, Yanting Chen, Wenxing Guo, Qi Jin, Naifan Zhang, Kexin Zhang, Ying Yang, and Ziyun Pan participated in this study and collected data. Ziyun Pan was responsible for the analysis of urinary and blood samples and quality control. Wen Wu, Yanting Chen, Wenxing Guo, Qi Jin, Naifan Zhang, Kexin Zhang and Ying Yang analyzed the data, wrote and reviewed the paper. Wanqi Zhang drafted the paper, all authors contributed to and approved the final draft of the manuscript.

Informed Consent Statement: Informed consent was obtained from all subjects involved in the study.

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Received : 03 Apr 2023
Accepted : 28 Mar 2023
Published : 29 Mar 2023
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ISSN : 2475-9155
Launched : 2016
JSM Head and Neck Cancer-Cases and Reviews
ISSN : 2573-1610
Launched : 2016
JSM General Surgery Cases and Images
ISSN : 2573-1564
Launched : 2016
JSM Anatomy and Physiology
ISSN : 2573-1262
Launched : 2016
JSM Dental Surgery
ISSN : 2573-1548
Launched : 2016
Annals of Emergency Surgery
ISSN : 2573-1017
Launched : 2016
Annals of Mens Health and Wellness
ISSN : 2641-7707
Launched : 2017
Journal of Preventive Medicine and Health Care
ISSN : 2576-0084
Launched : 2018
Journal of Chronic Diseases and Management
ISSN : 2573-1300
Launched : 2016
Annals of Vaccines and Immunization
ISSN : 2378-9379
Launched : 2014
JSM Heart Surgery Cases and Images
ISSN : 2578-3157
Launched : 2016
Annals of Reproductive Medicine and Treatment
ISSN : 2573-1092
Launched : 2016
JSM Brain Science
ISSN : 2573-1289
Launched : 2016
JSM Biomarkers
ISSN : 2578-3815
Launched : 2014
JSM Biology
ISSN : 2475-9392
Launched : 2016
Archives of Stem Cell and Research
ISSN : 2578-3580
Launched : 2014
Annals of Clinical and Medical Microbiology
ISSN : 2578-3629
Launched : 2014
JSM Pediatric Surgery
ISSN : 2578-3149
Launched : 2017
Journal of Memory Disorder and Rehabilitation
ISSN : 2578-319X
Launched : 2016
JSM Tropical Medicine and Research
ISSN : 2578-3165
Launched : 2016
JSM Head and Face Medicine
ISSN : 2578-3793
Launched : 2016
JSM Cardiothoracic Surgery
ISSN : 2573-1297
Launched : 2016
JSM Bone and Joint Diseases
ISSN : 2578-3351
Launched : 2017
JSM Bioavailability and Bioequivalence
ISSN : 2641-7812
Launched : 2017
JSM Atherosclerosis
ISSN : 2573-1270
Launched : 2016
Journal of Genitourinary Disorders
ISSN : 2641-7790
Launched : 2017
Journal of Fractures and Sprains
ISSN : 2578-3831
Launched : 2016
Journal of Autism and Epilepsy
ISSN : 2641-7774
Launched : 2016
Annals of Marine Biology and Research
ISSN : 2573-105X
Launched : 2014
JSM Health Education & Primary Health Care
ISSN : 2578-3777
Launched : 2016
JSM Communication Disorders
ISSN : 2578-3807
Launched : 2016
Annals of Musculoskeletal Disorders
ISSN : 2578-3599
Launched : 2016
Annals of Virology and Research
ISSN : 2573-1122
Launched : 2014
JSM Renal Medicine
ISSN : 2573-1637
Launched : 2016
Journal of Muscle Health
ISSN : 2578-3823
Launched : 2016
JSM Genetics and Genomics
ISSN : 2334-1823
Launched : 2013
JSM Anxiety and Depression
ISSN : 2475-9139
Launched : 2016
Clinical Journal of Heart Diseases
ISSN : 2641-7766
Launched : 2016
Annals of Medicinal Chemistry and Research
ISSN : 2378-9336
Launched : 2014
JSM Pain and Management
ISSN : 2578-3378
Launched : 2016
JSM Women's Health
ISSN : 2578-3696
Launched : 2016
Clinical Research in HIV or AIDS
ISSN : 2374-0094
Launched : 2013
Journal of Endocrinology, Diabetes and Obesity
ISSN : 2333-6692
Launched : 2013
Journal of Substance Abuse and Alcoholism
ISSN : 2373-9363
Launched : 2013
JSM Neurosurgery and Spine
ISSN : 2373-9479
Launched : 2013
Journal of Liver and Clinical Research
ISSN : 2379-0830
Launched : 2014
Journal of Drug Design and Research
ISSN : 2379-089X
Launched : 2014
JSM Clinical Oncology and Research
ISSN : 2373-938X
Launched : 2013
JSM Bioinformatics, Genomics and Proteomics
ISSN : 2576-1102
Launched : 2014
JSM Chemistry
ISSN : 2334-1831
Launched : 2013
Journal of Trauma and Care
ISSN : 2573-1246
Launched : 2014
JSM Surgical Oncology and Research
ISSN : 2578-3688
Launched : 2016
Annals of Food Processing and Preservation
ISSN : 2573-1033
Launched : 2016
Journal of Radiology and Radiation Therapy
ISSN : 2333-7095
Launched : 2013
JSM Physical Medicine and Rehabilitation
ISSN : 2578-3572
Launched : 2016
Annals of Clinical Pathology
ISSN : 2373-9282
Launched : 2013
Annals of Cardiovascular Diseases
ISSN : 2641-7731
Launched : 2016
Journal of Behavior
ISSN : 2576-0076
Launched : 2016
Annals of Clinical and Experimental Metabolism
ISSN : 2572-2492
Launched : 2016
Clinical Research in Infectious Diseases
ISSN : 2379-0636
Launched : 2013
JSM Microbiology
ISSN : 2333-6455
Launched : 2013
Journal of Urology and Research
ISSN : 2379-951X
Launched : 2014
Journal of Family Medicine and Community Health
ISSN : 2379-0547
Launched : 2013
Annals of Pregnancy and Care
ISSN : 2578-336X
Launched : 2017
JSM Cell and Developmental Biology
ISSN : 2379-061X
Launched : 2013
Annals of Aquaculture and Research
ISSN : 2379-0881
Launched : 2014
Clinical Research in Pulmonology
ISSN : 2333-6625
Launched : 2013
Journal of Immunology and Clinical Research
ISSN : 2333-6714
Launched : 2013
Annals of Forensic Research and Analysis
ISSN : 2378-9476
Launched : 2014
JSM Biochemistry and Molecular Biology
ISSN : 2333-7109
Launched : 2013
Annals of Breast Cancer Research
ISSN : 2641-7685
Launched : 2016
Annals of Gerontology and Geriatric Research
ISSN : 2378-9409
Launched : 2014
Journal of Sleep Medicine and Disorders
ISSN : 2379-0822
Launched : 2014
JSM Burns and Trauma
ISSN : 2475-9406
Launched : 2016
Chemical Engineering and Process Techniques
ISSN : 2333-6633
Launched : 2013
Annals of Clinical Cytology and Pathology
ISSN : 2475-9430
Launched : 2014
JSM Allergy and Asthma
ISSN : 2573-1254
Launched : 2016
Journal of Neurological Disorders and Stroke
ISSN : 2334-2307
Launched : 2013
Annals of Sports Medicine and Research
ISSN : 2379-0571
Launched : 2014
JSM Sexual Medicine
ISSN : 2578-3718
Launched : 2016
Annals of Vascular Medicine and Research
ISSN : 2378-9344
Launched : 2014
JSM Biotechnology and Biomedical Engineering
ISSN : 2333-7117
Launched : 2013
Journal of Hematology and Transfusion
ISSN : 2333-6684
Launched : 2013
JSM Environmental Science and Ecology
ISSN : 2333-7141
Launched : 2013
Journal of Cardiology and Clinical Research
ISSN : 2333-6676
Launched : 2013
JSM Nanotechnology and Nanomedicine
ISSN : 2334-1815
Launched : 2013
Journal of Ear, Nose and Throat Disorders
ISSN : 2475-9473
Launched : 2016
JSM Ophthalmology
ISSN : 2333-6447
Launched : 2013
Journal of Pharmacology and Clinical Toxicology
ISSN : 2333-7079
Launched : 2013
Annals of Psychiatry and Mental Health
ISSN : 2374-0124
Launched : 2013
Medical Journal of Obstetrics and Gynecology
ISSN : 2333-6439
Launched : 2013
Annals of Pediatrics and Child Health
ISSN : 2373-9312
Launched : 2013
JSM Clinical Pharmaceutics
ISSN : 2379-9498
Launched : 2014
JSM Foot and Ankle
ISSN : 2475-9112
Launched : 2016
JSM Alzheimer's Disease and Related Dementia
ISSN : 2378-9565
Launched : 2014
Journal of Addiction Medicine and Therapy
ISSN : 2333-665X
Launched : 2013
Journal of Veterinary Medicine and Research
ISSN : 2378-931X
Launched : 2013
Annals of Public Health and Research
ISSN : 2378-9328
Launched : 2014
Annals of Orthopedics and Rheumatology
ISSN : 2373-9290
Launched : 2013
Journal of Clinical Nephrology and Research
ISSN : 2379-0652
Launched : 2014
Annals of Community Medicine and Practice
ISSN : 2475-9465
Launched : 2014
Annals of Biometrics and Biostatistics
ISSN : 2374-0116
Launched : 2013
JSM Clinical Case Reports
ISSN : 2373-9819
Launched : 2013
Journal of Cancer Biology and Research
ISSN : 2373-9436
Launched : 2013
Journal of Surgery and Transplantation Science
ISSN : 2379-0911
Launched : 2013
Journal of Dermatology and Clinical Research
ISSN : 2373-9371
Launched : 2013
JSM Gastroenterology and Hepatology
ISSN : 2373-9487
Launched : 2013
Annals of Nursing and Practice
ISSN : 2379-9501
Launched : 2014
JSM Dentistry
ISSN : 2333-7133
Launched : 2013
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