A systematic review on the association of month and season of birth with future anthropometric measures.

BACKGROUND: Prenatal factors might have some health impacts later in life. This study aims to systematically review the current literature on the association between season and month of birth with birth weight as well as with weight status in childhood. METHODS: The search process was conducted in electronic databases, including papers published until April 2019 in ISI Web of Science, PubMed, Scopus, and Google Scholar. The following search strategy was used with MeSH terms: ("Seasons"[Mesh]) AND ("Obesity"[Mesh] OR "Pediatric Obesity"[Mesh] OR "Obesity, Abdominal"[Mesh] OR "Overweight"[Mesh] OR "Birth Weight"[Mesh] OR "Body Height"[Mesh]). After the selection process, 50 papers were included in this systematic review. RESULTS: This review showed that individuals who are born in cold season (winter month) have higher body mass index (BMI) and weight in childhood. Birth in March was associated with lower weight and BMI in boys according to most studies. All studies, except one of them, showed that season/month of birth was not associated with birth weight. CONCLUSIONS: This systematic review confirms a relationship between season and month of birth with birth weight and body size in childhood; however, the impact of confounding factors, for example, vitamin D status, should be considered in the underlying pathway of this association. IMPACT: The results provide evidence for the effect of season and month of birth on body size in childhood. Our systematic review suggests that there is no pattern between birth weight and season/month of birth, and the occurrence of low birth weight was more frequent among infants who were born in summer than others. Further research should focus on identifying the impact of confounding factors, for example, vitamin D status in the underlying pathway of this association. There was response to the controversial findings about the effect of environment factors, such as season and month of birth, and future anthropometric indices, such as obesity, weight, height, and birth weight. Obesity is a complex and multifactorial disorder; the findings of the current study would be useful in determining the relationship pathway between the season and the month of birth with other underlying factors for childhood obesity.

Effects of Probiotics on Nonalcoholic Fatty Liver Disease in Obese Children and Adolescents.

OBJECTIVES: This study aims to evaluate the effects of some probiotics on sonographic and biochemical nonalcoholic fatty liver disease (NAFLD). METHODS: This randomized triple-blind trial was conducted among 64 obese children with sonographic NAFLD. They were randomly allocated to receive probiotic capsule (containing Lactobacillus acidophilus ATCC B3208, 3 × 10 colony forming units [CFU]; Bifidobacterium lactis DSMZ 32269, 6 × 10 CFU; Bifidobacterium bifidum ATCC SD6576, 2 × 10 CFU; Lactobacillus rhamnosus DSMZ 21690, 2 × 10 CFU) or placebo for 12 weeks. RESULTS: After intervention, in the probiotic group the mean levels of alanine aminotransferase decreased from 32.8 (19.6) to 23.1 (9.9) U/L (P = 0.02) and mean aspartate aminotransferase decreased from 32.2 (15.7) to 24.3 (7.7) U/L (P = 0.02). Likewise the mean cholesterol, low-density lipoprotein-C, and triglycerides as well as waist circumference decreased in the intervention group, without significant change in weight, body mass index, and body mass index z score. After the trial, normal liver sonography was reported in 17 (53.1%) and 5 (16.5%) of patients in the intervention and placebo groups, respectively. CONCLUSIONS: The present findings suggest that a course of the abovementioned probiotic compound can be effective in improving pediatric NAFLD.

A randomized controlled trial on the effects of jujube fruit on the concentrations of some toxic trace elements in human milk.

BACKGROUND: This study aims to investigate the concentrations of lead, cadmium, and arsenic in the human milk, and to assess the effect of jujube fruit consumption by lactating mothers in reducing the concentration of these heavy metals in their milk. MATERIALS AND METHODS: This randomized controlled trial was conducted in 2014 among forty postpartum mothers in Isfahan, the second largest and polluted city in Iran. Mothers were randomized into two groups; the intervention group received 15 g/day of fresh jujube fruit, and the controls received routine care for 8 weeks. RESULTS: In the beginning, the concentrations of lead, cadmium, and arsenic were high, without significant difference between groups. The mean (standard deviation) concentrations of lead, cadmium, and arsenic were 29.49 (16.6), 4.65 (3.51), and 1.23 (0.63) µg/L, respectively. The smoothed empirical distribution of environmental pollutants showed that in both groups the mean values and variance of toxic metals decreased after 8 weeks, with a sharper decline in the intervention group. Quantile regression analysis showed that in the intervention group, lead concentration decreased by 2.54 µg/L at the 90th quintile, and cadmium decreased by 0.19 µg/Lat 75th quintile; without significant change in arsenic level. The corresponding figures were not significant in the control group. CONCLUSION: The concentrations of heavy metals were high in human milk, and the consumption of jujube fruit had some beneficial effects in reducing these harmful elements. Pregnant and lactating mothers should be advised to reduce their exposure to environmental pollutants, and consumption of some natural medicinal foods can be useful in reducing the concentration of pollutants in human milk. Because of numerous benefits of breast milk, in spite of the existence of some toxic trace elements, breastfeeding must be encouraged because such contaminants are also found in water and formula. The impact of the current findings on the primary prevention of chronic disease should be determined in future longitudinal studies.

The relationship of serum vitamin D and Zinc in a nationally representative sample of Iranian children and adolescents: The CASPIAN-III study.

Background: Vitamin D (VitD) deficiency is a common worldwide problem. Some previous studies have shown that both Zinc (Zn) and VitD deficiency are prevalent in Iran. This study aimed to assess the relationship of serum Zn and vitamin D levels in a nationally representative sample of Iranian children and adolescents. Methods: This case-control study was conducted as a sub-study of a school-based surveillance program entitled "the CASPIAN-III Study". An equal number of individuals with and without hypovitaminosis D including 330 participants aged 10 to 18 years were selected. The correlation of serum 25 hydroxy vitamin D (25(OH) D), cardiometabolic factors and Zn concentrations was determined. Statistical analysis was done using one-way analysis of variance (ANOVA), Pearson's correlation, linear regression, and logistic regression. Results: The mean age was not significantly different in participants with and without hypovitaminosis D (14.74±2.52 vs. 14.74±2.66 years, respectively, p>0.05). The mean 25(OH) D level was 6.34±1.47ng/ml in the group with hypovitaminosis D and 39.27±6.42ng/ml in controls. The mean Zn level was significantly lower in the hypovitaminosis D group than in controls (1.15±0.26 vs. 1.43±0.32µg/ml, respectively, p<0.001). The Pearson's analysis showed a positive and significant correlation between Zn and 25(OH) D serum levels (p<0.0001). Odds ratios analysis for VitD level between various quartiles of serum zinc concentration for all participants showed that the odds of higher levels of VitD increased by higher levels of Zn. Conclusion: We found significant associations between low serum concentrations of zinc and 25(OH) D. Food fortification or mineral supplementation should be considered in future health programs.

Systematic review on adverse birth outcomes of climate change.

BACKGROUND: Climate change and global warming have significant effects on human health. This systematic review presents the effects of the climate changes on pregnancy outcomes. MATERIALS AND METHODS: The search process was conducted in electronic databases including ISI Web of Knowledge, PubMed, Scopus, and Google Scholar using key words of "environmental temperature" "pregnancy" "low birth weight (LBW)" "pregnancy outcome," "climate change," "preterm birth (PTB)," and a combination of them. We did not consider any time limitation; English-language papers were included. The related papers were selected in three phases. After quality assessment, two reviewers extracted the data while the third reviewer checked their extracted data. Finally, 15 related articles were selected and included in the current study. RESULTS: Approximately all studies have reported a significant relationship between exposure variable and intended outcomes including eclampsia, preeclampsia, cataract, LBW, PTB, hypertension, sex ratio and length of pregnancy. According to conducted studies, decrease in birth weight is more possible in cold months. Increase in temperature was followed by increase in PTB rate. According to most of the studies, eclampsia and preeclampsia were more prevalent in cold and humid seasons. Two spectrums of heat extent, different seasons of the year, sunlight intensity and season of fertilization were associated with higher rates of PTB, hypertension, eclampsia, preeclampsia, and cataract. CONCLUSION: Climate change has unfavorable effects on eclampsia, preeclampsia, PTB, and cataract. The findings of this review confirm the crucial importance of the adverse health effects of climate change especially in the perinatal period.

A systematic review on the association of serum selenium and metabolic syndrome.

BACKGROUND: This systematic review paper aims to study the experimental and human studies on the relationship between metabolic syndrome (MetS), its component and selenium (Se) concentration. MATERIALS AND METHODS: The literature was searched in PubMed, Scopus, and Google Scholar databases with no time limitation using MetS X and Se key words in medical subject heading. The related papers were selected in three phases. After quality assessment, two reviewers extracted the data, whereas the third reviewer checked their extracted data. All evidence comes from experimental and laboratory studies. RESULTS: Finally, 18 articles were included. While, some studies documented that as an antioxidant agent, Se might be correlated with endothelial function, large controversy exists about the type of correlation including positive, negative, and no correlation between MetS and Se levels in body. Some of the reviewed studies were focused on antioxidant supplementation effects on MetS, results also varied in this regard. CONCLUSION: This inconsistency could be because of diversity in study design, population, lack of special focus on Se and MetS, and finally the complex nature of MetS.

Systematic review on the association of abdominal obesity in children and adolescents with cardio-metabolic risk factors.

BACKGROUND: The adverse health effects of abdominal obesity are well documented in adults, but such association remains to be determined in the pediatric age group. This study aims to perform a systematic review on the association between abdominal obesity and cardio-metabolic factors such as dyslipidemia, hypertension, and hyperglycemia among children and adolescents. MATERIALS AND METHODS: A systematic literature search was conducted using PubMed, Scopus and Google Scholar databases to May 2014. Two independent reviewers identified relevant papers in several steps. After studying the titles and texts of documents, repeated and irrelevant ones were excluded. The search was refined to the English language. We did not consider any time limitation. Studies with different measuring methods of abdominal obesity were included. Studies with abdominal obese patients secondary to other disease were excluded from the study. In final, the data of association of cardio-metabolic risk factors and abdominal obesity extracted from studies. RESULTS: Overall, 3966 articles were reviewed, and 61 of them were studied according to the inclusion and exclusion criteria. Waist circumference (WC), waist-to-height ratio, and waist-to-hip ratio were the most common indexes used for defining abdominal obesity. The association of high blood pressure with increasing WC was seen in several studies. The association of other cardio-metabolic risk factors was seen in some studies. CONCLUSION: Whatever the definition used for abdominal obesity and whatever the methods used for anthropometric measurements, central body fat deposition in children and adolescents increases the risk of cardio-metabolic risk factors. Therefore, more attention should be paid to abdominal obesity of children and adolescents both in clinical practice and in epidemiological studies.

A systematic review and meta-analysis on screening lipid disorders in the pediatric age group.

BACKGROUND: Different viewpoints exist about lipid screening in all children or only in children with positive family history (FH) of premature cardiovascular diseases (CVDs) or hypercholesterolemia. This systematic review and meta-analysis aim to assess the effectiveness of lipid screening in children and adolescents according to the existence of positive FH of CVD risk factors. MATERIALS AND METHODS: PubMed, Scopus, and Google scholar were searched to identify relevant papers that were published from November 1980 until 30 November 2013. Irrelevant studies were set aside after studying their title, abstract, and full text. Then, the relevant studies were assessed by using a quality appraisal checklist. We used random effect model for meta-analysis and calculating the total estimation of sensitivity, specificity, and the positive predictive value (PPV) of FH in predicting dyslipidemia among children and adolescents. RESULTS: Overall, 17,214 studies were identified in the primary search, out of which 19 primary studies were qualified for study entry. The sensitivity of positive FH of premature CVD or dyslipidemia for predicting dyslipidemia among children varied between 15 and 93. Moreover, the effectiveness of screening children for dyslipidemia according to premature CVD or dyslipidemia in their relatives was low in 86.9% of the primary studies. The total estimation of sensitivity, specificity, and predictive value was 42.6, 59, and 20.7, respectively, according to the meta-analysis results. CONCLUSION: The present meta-analysis indicated that selecting target population for screening children and adolescents for dyslipidemia according to their FH has low sensitivity.

Association of 25-hydroxy Vitamin D levels with indexes of general and abdominal obesity in Iranian adolescents: The CASPIAN-III study.

BACKGROUND: This study aimed to determine the association of serum 25-hydroxy Vitamin D (25(OH)D) levels with measures of general and abdominal obesity in Iranian adolescents. MATERIALS AND METHODS: This nationwide cross-sectional study was conducted among 1090 students, aged 10-18 years, living in 27 provinces in Iran. Serum concentration of 25(OH)D was analyzed quantitatively by direct competitive immunoassay chemiluminescence method. Body mass index (BMI) and waist-to-height ratio (WHtR) were considered as measures of generalized and abdominal obesity, respectively. RESULTS: Study participants consisted of 1090 adolescents (51.9% boy and 67.1% urban residents) with mean age, BMI, and waist circumference of 14.7 (2.6) years, 19.3 (4.2) kg/m(2), and 67.82 (12.23) cm, respectively. The median serum 25(OH)D was 13.0 ng/mL (interquartile range: 20.6). Overall, 40% of participants were Vitamin D deficient, and 39% were Vitamin D insufficient. Serum 25(OH)D level was not associated with BMI and WHtR. CONCLUSION: We did not document any significant association between serum 25(OH)D level and anthropometric measures in adolescents. This finding may be because of considerably high prevalence of hypovitaminosis D in the study population.

Is an Exercise-Based Injury Prevention Programme Effective in Team Handball Players? A Systematic Review and Meta-Analysis.

OBJECTIVE: This systematic review and meta-analysis aimed to assess the effectiveness of exercise-based injury prevention programmes in preventing sports injuries in team handball players. DATA SOURCES: Two independent researchers performed a systematic search in the electronic databases Scopus, PubMed, Web of Science (WOS), SPORTDiscus, and CINAHL from inception until Aprile 2023. STUDY SELECTION: Studies were included if they were randomized-controlled or prospective cohort trials, contained a population of competitive team handball players, included an intervention designed specifically to prevent or reduce the risk of team handball injury, and reported injury incidence rates specific to team handball players. Two researchers independently assessed trials for inclusion criteria and methodological quality. DATA EXTRACTION: Study design, intervention details, participant characteristics, and the number of injuries in each group were extracted from each study by two independent researchers. The outcome of interest was the incidence rate of injury. Injury data were classified into 5 groups: lower extremity injuries, shoulder injuries, knee injuries, ankle sprains, or ACL injuries. Extracted data were analyzed by Comprehensive Meta-Analysis software, version 3.0 (CMA.V2) using a random-effects model to compute the overall effect estimates of injury prevention programmes in reducing the risk of injuries. Odds ratios (ORs) with 95% CIs were calculated based on the number of injuries in each group. DATA SYNTHESIS: Meta-analyses were conducted independently for each injury classification. Results indicate that prevention programmes significantly reduced the risk of shoulder injuries (OR, 0.56; 95% CI, 0.36-0.87; P = 0.01), lower extremity (OR, 0.59; 95% CI, 0.37-0.98; P = 0.03), knee (OR, 0.53; 95% CI, 0.35-0.78; P = 0.002) and ankle sprains (OR, 0.57; 95% CI, 0.40-0.81; P = 0.002), and ACL ruptures (OR, 0.67; 95% CI, 0.45-0.97; P = 0.03) in team handball players. CONCLUSION: In team handball players, prevention programmes appear effective in reducing the risk of shoulder, lower extremity, knee, ankle, and ACL injuries.

Association between anogenital distance as a noninvasive index in the diagnosis and prognosis of reproductive disorder: A systematic review.

Background: There are 2 measures of anogenital distance (AGD) in men and women. AGD has been used as an indicator of fetal androgen dysfunction and an adverse outcome in adulthood. Some studies have shown the association of AGD as a predictor in the diagnosis and prognosis of diseases and disorders. Objective: To systematically summarize the latest evidence for presenting AGD as a new approach for prognosis and early diagnosis of diseases. Materials and Methods: A systematic review of the available literature was performed using Medline via PubMed, Scopus, and ISI Web of Knowledge up to July 2021, using search terms "anogenital distance" OR "anogenital index" OR "ano genital distance" OR "ano genital index". Language restrictions were not imposed. Results: After reviewing the retrieved articles, 47 unique studies were included in this systematic review. Different outcomes, including endometriosis, prostate cancer, polycystic ovary syndrome, pelvic organ prolapse, hypospadias, cryptorchidism, fertility and semen parameters, maternal and birth development, and ovarian and gynecological-related disorders, have been studied in the included evidence. A negative association was observed between AGD and endometriosis and hypospadias and a positive association between AGD and prostate cancer, polycystic ovary syndrome, male fetal gender, and fertility parameters. Conclusion: Using quantitative indicators such as AGD may be a useful clinical tool for the diagnosis of diseases. Although many studies have shown an association between AGD and diseases, some factors, including different measurement methods, different measurement tools, age, and different definitions of AGD, can be involved in the variation of AGD.

N,N'-Dibenzyl-N''-(2-chloro-2,2-difluoro-acet-yl)phospho-ric triamide.

In the title mol-ecule, C(16)H(17)ClF(2)N(3)O(2)P, the N-H unit of the C(=O)NHP(=O) fragment adopts a syn orientation with respect to the P=O group. The two F atoms and the Cl atom of the ClF(2)C group are disordered over two sets of sites with refined occupancies of 0.605 (6) and 0.395 (6). In the crystal, mol-ecules are linked via N-H⋯O=C hydrogen bonds the and the (N-H⋯)(N-H⋯)O=P group into chains along [010].

Cyclo-hexyl-ammonium acetate-N,N',N''-tricyclo-hexyl-phospho-ric triamide (1/1).

In the phospho-ric triamide mol-ecule of the title compound, C(6)H(14)N(+)·C(2)H(3)O(2) (-)·C(18)H(36)N(3)OP, the P atom displays a distorted tetra-hedral geometry and the cyclo-hexyl rings adopt chair conformations with the NH groups in equatorial positions. In the crystal, the cations, anions and phosphoric triamide mol-ecules are linked via N-H⋯O hydrogen bonds into a two-dimensional array parallel to the bc plane. The O atom of the P(O) group acts as a double-hydrogen-bond acceptor.

Bis(pyrrolidin-1-yl)phosphinic (2,4-di-fluoro-benzo-yl)amide.

The P atom in the title mol-ecule, C(15)H(20)F(2)N(3)O(2)P, is in a distorted tetra-hedral P(O)(N)(N)(2) environment. The phosphoryl group and the NH unit adopt a syn orientation with respect to each other. An F atom at position 2 and an H atom at position 6 are found to occupy similar sites in a 0.70:0.30 ratio and were refined with fixed occupancies. The pyrrolidin-1-yl rings are disordered over two sets of sites, with site occupancies of 0.566 (6) and 0.434 (6), and were refined using a two-part model. In the crystal, hydrogen-bonded dimers linked by pairs of N-H⋯O(P) hydrogen bonds generate an R(2) (2)(8) ring motif.

A second monoclinic polymorph of N-[bis-(morpholin-4-yl)phosphino-yl]-4-fluoro-benzamide with the P2(1)/n space group.

A second monoclinic polymorph of the title mol-ecule, C(15)H(21)FN(3)O(4)P, is reported in the space group P2(1)/n and compared to the previously reported C2/c space group [Gholivand et al. (2006 ▶). Polyhedron, 25, 711-721]. The asymmetric unit of the title compound consists of two independent mol-ecules. The P atoms adopt a distorted tetra-hedral environment. In the C(O)NHP(O) fragment, the P=O and the N-H groups are in a syn conformation with respect to each other and in the crystal, inter-molecular N-H⋯O=P hydrogen bonds form dimeric aggregates.

N,N'-Dibenzyl-N''-(2-chloro-acet-yl)-N,N'-dimethyl-phospho-ric triamide.

In the title mol-ecule, C(18)H(23)ClN(3)O(2)P, the P atom is bonded in a distorted tetra-hedral environment. The P=O and N-H groups are syn with respect to each other. The angles at the tertiary N atoms confirm their sp(2) character. In the crystal, pairs of inter-molecular P=O⋯H-N hydrogen bonds form centrosymmetric dimers.

N,N'-Bis(2-methyl-phen-yl)-N''-(2,2,2-trichloro-acet-yl)phospho-ric triamide.

In the title compound, C(16)H(17)Cl(3)N(3)O(2)P, the P-N bonds in the P(O)[NH(2-CH(3))C(6)H(4)](2) unit [1.623 (4) and 1.637 (3) Å] are shorter than the P-N bond in the C(O)NHP(O) fragment [1.704 (3) Å]. The phosphoryl and carbonyl groups are anti with respect to each other and the P atom has a distorted tetra-hedral configuration. In the crystal, adjacent mol-ecules are linked via N-H⋯O(P) and N-H⋯O(C) hydrogen bonds into an extended chain parallel to [101].

Nutritional supplements and mother's milk composition: a systematic review of interventional studies.

BACKGROUND: This study aims to systematically review the effects of maternal vitamin and/or mineral supplementation on the content of breast milk. METHODS: We systematically searched electronic databases including Medline via PubMed, Scopus and ISI Web of Science till May 24, 2018. The following terms were used systematically in all mentioned databases: ("human milk" OR "breast milk" OR "breast milk composition" OR "human breast milk composition" OR "composition breast milk" OR "mother milk" OR "human breast milk" OR "maternal milk") AND ("vitamin a" OR "retinol" OR "retinal" OR "retinoic acid" OR "beta-carotene" OR "beta carotene" OR "ascorbic acid" OR "l-ascorbic acid" OR "l ascorbic acid" OR "vitamin c" OR "vitamin d" OR "cholecalciferol" OR "ergocalciferol" OR "calciferol" OR "vitamin e" OR "tocopherol" OR "tocotrienol" OR "alpha-tocopherol" OR "alpha tocopherol" OR "α-tocopherol" OR "α tocopherol" OR "vitamin k" OR "vitamin b" OR "vitamin b complex" OR "zinc" OR "iron" OR "copper" Or "selenium" OR "manganese" OR "magnesium") and we searched Medline via Medical subject Headings (MeSH) terms. We searched Google Scholar for to increase the sensitivity of our search. The search was conducted on human studies, but it was not limited to the title and abstract. Methodological quality and risk of bias of included studies were evaluated by Jadad scale and Cochrane risk of bias tools, respectively. RESULTS: This review included papers on three minerals (zinc, iron, selenium) and 6 vitamins (vitamin A, B, D, C, E and K) in addition to multi-vitamin supplements. Although studies had different designs, e.g. not using random allocation and/or blinding, our findings suggest that maternal use of some dietary supplements, including vitamin A, D, vitamin B1, B2 and vitamin C might be reflected in human milk. Vitamin supplements had agreater effect on breast milk composition compared to minerals. Higher doses of supplements showed higher effects and they were reflected more in colostrum than in the mature milk. CONCLUSION: Maternal dietary vitamin and/or mineral supplementation, particularly fat- soluble vitamins, vitamin B1, B2 and C might be reflected in the breast milk composition. No difference was found between mega dose and single dose administration of minerals.

Parasite-based interventions in systemic lupus erythematosus (SLE): A systematic review.

BACKGROUND: The hygiene hypothesis proposed in 1989 expresses that allergic and infectious diseases are inversely related. Accordingly, it has been demonstrated that infection with some microorganisms such as parasites and helminths can provide a potential immunity and prevent the onset of some life-threatening autoimmune diseases like systemic lupus erythematosus (SLE). Therefore, in this comprehensive study, we systematically reviewed and discussed the use of live parasites or parasitic products in the treatment of mouse models of SLE. METHODS: The present systematic review was performed using the following search terms: ("systemic lupus erythematosus" OR "SLE" OR "lupus") AND ("parasite" OR "protozoa" OR "helminths" OR "worms" OR "helminth" OR "worm") in PubMed, Scopus, and Web of Science online databases. We included studies reporting the effect of any intervention using parasites or parasitic-based products on animal models of SLE, which were published until January 20th, 2021 without any language or date restrictions. For each included study, we extracted the authors' names, publication year, type of animal, number of groups, types of intervention, sample size, changes in immunologic cells, auto-Abs, cytokines, and blood cells count, urine analysis, histological analysis of kidney/spleen/liver, outcome and survival. (PROSPERO CRD42020160460). RESULTS: A total of 17 eligible articles were included in this systematic review. Sixteen out of the 17 studies reported immunomodulating changes in immunologic cells, cytokines, and/or auto-Abs in mouse models of SLE after using parasitic interventions compared to not-infected or control groups. Moreover, 14 studies reported decreased level of proteinuria and/or favorable kidney, liver, or spleen histological changes. CONCLUSION: In conclusion, we have demonstrated that parasites like Hymenolepis microstoma, TPC and ES-62 from Acanthocheilonema viteae, Plasmodium chabaudi, Schistosoma mansoni, and Toxoplasma gondii have favorable immunomodulating effects on SLE outcomes in lupus-prone mice.

The association between prenatal exposure to organochlorine compounds and neonatal thyroid hormone levels: a systematic review.

In this systematic review, the association between prenatal exposure to organochlorine pesticides (OCPs) and neonatal thyroid hormone levels was studied. A systematic search of scientific literature was performed from the PubMed, SCOPUS and ISI web of science electronic bibliographic databases. The search strategy for the review was [(organochlorine OR "organochlorine pesticides" OR "organochlorine pollutants" OR "organochlorine pollutant") AND ("thyroid hormone" OR triiodothyronine OR Thyroxine OR "fetal thyroid function" OR "thyroid function" OR "Thyroid Stimulating Hormone" AND "prenatal" AND "maternal exposure")] in English sources. In this review, 305 papers (PubMed: 30; Scopus: 29; ISI: 246) were identified through an electronic database search. Twenty-seven articles were assessed for eligibility, from which 16 qualified articles were selected for the final evaluation. The most common OCP metabolites which were evaluated in order were hexachlorobenzene (HCB) (13 studies), pp-dichlorodiphenyldichloroethylene (pp-DDE) (13 studies), hexachlorocyclohexane (HCH) (10 studies) and dichlorodiphenyltrichlorethane (DDT) (eight studies). A review of the documents related to the association of prenatal exposure of OCPs with fetal or neonatal thyroid function tests provides us with heterogeneous data in this field. Factors such as differences in the studied populations and their area, ethnic and genetic background, time and rate of exposure, possible interaction of other thyroid-disrupting environmental factors and dietary intake of micronutrients such as iodine and/or selenium are considered the main limitations for making an accurate conclusion. For some OCPs including DDT, DDE, HCH and HCB, there are supporting evidences, and it is suggested that their exposure could potentially alter the fetal thyroid function and consequently impair the neurodevelopment process of the infants.