Abnormal Development - Teratogens - Revision history

Z8600021 at 23:45, 18 April 2018

2018-04-18T23:45:11Z

← Older revision		Revision as of 09:45, 19 April 2018
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			* '''Nanoparticle-induced neuronal toxicity across placental barriers is mediated by autophagy and dependent on astrocytes'''{{#pmid:29610530\|PMID29610530}} The potential for maternal nanoparticle (NP) exposures to cause developmental toxicity in the fetus without the direct passage of NPs has previously been shown, but the mechanism remained elusive. We now demonstrate that exposure of cobalt and chromium NPs to BeWo cell barriers, an in vitro model of the human placenta, triggers impairment of the autophagic flux and release of interleukin-6. This contributes to the altered differentiation of human neural progenitor cells and DNA damage in the derived neurons and astrocytes."

	* '''Dispensing of potentially teratogenic drugs before conception and during pregnancy: a population-based study'''{{#pmid:25316196\|PMID25316196}} "To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). ...Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored." (More? [[Abnormal Development - Drugs]] \| [[Australian Drug Categories]] \| [[USA Drug Categories]])		* '''Dispensing of potentially teratogenic drugs before conception and during pregnancy: a population-based study'''{{#pmid:25316196\|PMID25316196}} "To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). ...Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored." (More? [[Abnormal Development - Drugs]] \| [[Australian Drug Categories]] \| [[USA Drug Categories]])

Z8600021 at 07:26, 6 April 2018

2018-04-06T07:26:00Z

← Older revision		Revision as of 17:26, 6 April 2018
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	When studying this topic remember the concept of "critical periods of development" that will affect the overall impact of the above listed factors, as outlined in the table below. This can be extended to the potential differences between prenatal and postnatal effects, for example with infections and outcomes.		When studying this topic remember the concept of "critical periods of development" that will affect the overall impact of the above listed factors, as outlined in the table below. This can be extended to the potential differences between prenatal and postnatal effects, for example with infections and outcomes.

			{{Critical Periods table}}

Z8600021 at 07:25, 6 April 2018

2018-04-06T07:25:14Z

Show changes

Z8600021 at 03:52, 15 February 2018

2018-02-15T03:52:57Z

← Older revision		Revision as of 13:52, 15 February 2018
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	* '''Dispensing of potentially teratogenic drugs before conception and during pregnancy: a population-based study'''~~<ref name=~~PMID25316196~~><pubmed>25316196</pubmed></ref>~~ "To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). ...Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored." (More? [[Abnormal Development - Drugs]] \| [[Australian Drug Categories]] \| [[USA Drug Categories]])		* '''Dispensing of potentially teratogenic drugs before conception and during pregnancy: a population-based study'''{{#pmid:25316196\|PMID25316196}} "To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). ...Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored." (More? [[Abnormal Development - Drugs]] \| [[Australian Drug Categories]] \| [[USA Drug Categories]])
	* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''~~<ref><pubmed>~~20561110~~</pubmed></ref>~~ "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."
	* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' <ref>Lim JH, Kim SH, Shin IS, Park NH, Moon C, Kang SS, Kim SH, Park SC, Kim JC. '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' Birth Defects Res (Part B) 92:69-76, 2011. [http://www.ncbi.nlm.nih.gov/pubmed/21254368 PMID:21254368~~]</ref>~~ "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."		* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''{{#pmid:20561110\|PMID20561110}} "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."

			* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.'''{{#pmid:21254368\|PMID21254368}} "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."
	\|}		\|}

Z8600021 at 00:01, 13 December 2016

2016-12-13T00:01:18Z

← Older revision		Revision as of 10:01, 13 December 2016
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	* '''Maternal diet''' the best characterised is the role of [[Abnormal Development - Folic Acid and Neural Tube Defects\|low folic acid]] and Neural Tube Defects (NTDs) see also abnormal neural development and Neural Tube Defects (NTDs). More recently the focus has been on [[Abnormal Development - Iodine Deficiency\|dietary iodine]] levels and the role they also play on neural development.		* '''Maternal diet''' the best characterised is the role of [[Abnormal Development - Folic Acid and Neural Tube Defects\|low folic acid]] and Neural Tube Defects (NTDs) see also abnormal neural development and Neural Tube Defects (NTDs). More recently the focus has been on [[Abnormal Development - Iodine Deficiency\|dietary iodine]] levels and the role they also play on neural development.

	* '''Maternal drugs''' effects either prescription drugs (therapeutic chemicals/agents, thalidomide limb development), non-prescription drugs (smoking), and illegal drugs (Cannabis/Marijuana, Methamphetamine/Amphetamine, Cocaine, Heroin, Lysergic Acid Diethylamide)		* '''Maternal drugs''' effects either prescription drugs (therapeutic chemicals/agents, thalidomide limb development), non-prescription drugs (smoking), and illegal drugs (Cannabis/Marijuana, Methamphetamine/Amphetamine, Cocaine, Heroin, Lysergic Acid Diethylamide). Some therapeutic compounds have teratogenic effects because they are also naturally occurring developmental signals, for example [[Developmental Signals - Retinoic acid\|retinoic acid]].

	* '''Environment''' ([[Abnormal_Development_-_Smoking\|smoking]], [[Abnormal Development - Chemicals\|chemicals]], [[Abnormal Development - Heavy Metals\|heavy metals]], radiation) and maternal endocrine function (maternal diabetes, thyroid development) and maternal stress.		* '''Environment''' ([[Abnormal_Development_-_Smoking\|smoking]], [[Abnormal Development - Chemicals\|chemicals]], [[Abnormal Development - Heavy Metals\|heavy metals]], radiation) and maternal endocrine function (maternal diabetes, thyroid development) and maternal stress.

Z8600021 at 01:08, 28 February 2015

2015-02-28T01:08:10Z

← Older revision		Revision as of 11:08, 28 February 2015
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			{{Header}}
	{{Educational Warning}}		{{Educational Warning}}
	==Introduction==		==Introduction==
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	'''Search Pubmed:''' [http://www.ncbi.nlm.nih.gov/pubmed?term=teratogen teratogen] \| [http://www.ncbi.nlm.nih.gov/pubmed?term=teratogenesis teratogenesis]		'''Search Pubmed:''' [http://www.ncbi.nlm.nih.gov/pubmed?term=teratogen teratogen] \| [http://www.ncbi.nlm.nih.gov/pubmed?term=teratogenesis teratogenesis]

Z8600021 at 00:12, 13 November 2014

2014-11-13T00:12:18Z

← Older revision		Revision as of 10:12, 13 November 2014
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			* '''Dispensing of potentially teratogenic drugs before conception and during pregnancy: a population-based study'''<ref name=PMID25316196><pubmed>25316196</pubmed></ref> "To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). ...Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored." (More? [[Abnormal Development - Drugs]] \| [[Australian Drug Categories]] \| [[USA Drug Categories]])
	* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''<ref><pubmed>20561110</pubmed></ref> "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."		* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''<ref><pubmed>20561110</pubmed></ref> "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."
	* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' <ref>Lim JH, Kim SH, Shin IS, Park NH, Moon C, Kang SS, Kim SH, Park SC, Kim JC. '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' Birth Defects Res (Part B) 92:69-76, 2011. [http://www.ncbi.nlm.nih.gov/pubmed/21254368 PMID:21254368]</ref> "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."		* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' <ref>Lim JH, Kim SH, Shin IS, Park NH, Moon C, Kang SS, Kim SH, Park SC, Kim JC. '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' Birth Defects Res (Part B) 92:69-76, 2011. [http://www.ncbi.nlm.nih.gov/pubmed/21254368 PMID:21254368]</ref> "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."

Z8600021 at 00:05, 13 November 2014

2014-11-13T00:05:38Z

← Older revision		Revision as of 10:05, 13 November 2014
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	{{Viral Links}}		{{Viral Links}}

			{{Bacterial Links}}

	{{Abnormality Links}}		{{Abnormality Links}}
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			{\| class="wikitable mw-collapsible mw-collapsed"
			! More recent papers
			\|-
			\| [[File:Mark_Hill.jpg\|90px\|left]] {{Most_Recent_Refs}}

			Search term: [http://www.ncbi.nlm.nih.gov/pubmed/?term=teratogen ''teratogen'']

			<pubmed limit=5>teratogen</pubmed>
			\|}
	==Critical Periods of Development==		==Critical Periods of Development==

Z8600021 at 23:57, 12 November 2014

2014-11-12T23:57:39Z

← Older revision		Revision as of 09:57, 13 November 2014
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	{{Educational Warning}}		{{Educational Warning}}
	==Introduction==		==Introduction==
	[[File:Human-critical_periods_of_development.jpg\|thumb\|~~300px~~\|Human critical periods of development]]		[[File:Human-critical_periods_of_development.jpg\|thumb\|350px\|Human critical periods of development]]
	How and why do things go wrong in development? Embryological development is a robust biological system able to cope with many stresses without long-term consequences. When development does go wrong there are generally 3 major types groups: Genetic (inherited), Environmental (maternal) derived and Unknown (not determined or known) abnormalities. Also often not considered, is that pregnancy itself can also expose abnormalities in the mother (congenital heart disease, diabetes, reproductive disorders) that until the pregnancy had gone undetected.		How and why do things go wrong in development? Embryological development is a robust biological system able to cope with many stresses without long-term consequences. When development does go wrong there are generally 3 major types groups: Genetic (inherited), Environmental (maternal) derived and Unknown (not determined or known) abnormalities. Also often not considered, is that pregnancy itself can also expose abnormalities in the mother (congenital heart disease, diabetes, reproductive disorders) that until the pregnancy had gone undetected.


	* '''Infections''' collectively grouped under the acronym [[Abnormal Development - TORCH Infections\|TORCH]] for Toxoplasmosis, Other organisms (parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus) , Rubella, Cytomegalovirus and Hepatitis. See also the related topics on '''maternal hyperthermia''' and bacterial infections.		* '''Infections''' collectively grouped under the acronym [[Abnormal Development - TORCH Infections\|TORCH]] for Toxoplasmosis, Other organisms (parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus) , Rubella, Cytomegalovirus and Hepatitis. See also the related topics on '''maternal hyperthermia''' and bacterial infections.
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	* '''Teratogen synergism''', different environmental effects can act individually or in combination on the same developing system. For example, neural development can be impacted upon by alcohol (fetal alcohol syndrome), viral infection (rubella) and/or inadequate dietry folate intake (neural tube defects). These effects may also not be seen as a direct effect on a system or systems but result in a reduced birth weight and the potential postnatal developmental effects. Consider also this in relation to the increasing support to the '''fetal origins hypothesis'''.		* '''Teratogen synergism''', different environmental effects can act individually or in combination on the same developing system. For example, neural development can be impacted upon by alcohol (fetal alcohol syndrome), viral infection (rubella) and/or inadequate dietry folate intake (neural tube defects). These effects may also not be seen as a direct effect on a system or systems but result in a reduced birth weight and the potential postnatal developmental effects. Consider also this in relation to the increasing support to the '''fetal origins hypothesis'''.



	Use the page links below to explore specific teratogens.		Use the page links below to explore specific teratogens.

	:{{~~Template:~~Environmental}}		{{Environmental}}

	:{{Viral Links}}		{{Viral Links}}

	:{{~~Template:~~Abnormality Links}}		{{Abnormality Links}}

	== Some Recent Findings ==		== Some Recent Findings ==
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	* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''<ref><pubmed>20561110</pubmed></ref> "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."		* '''Teratogen Screening Using Transcriptome Profiling of Differentiating Human Embryonic Stem Cells'''<ref><pubmed>20561110</pubmed></ref> "Teratogens are substances that may cause defects in normal embryonic development while not necessarily being toxic in adults. Identification of possible teratogenic compounds has been historically beset by the species-specific nature of the teratogen response. To examine teratogenic effects on early human development we performed non-biased expression profiling of differentiating human embryonic and induced-pluripotent stem cells treated with several drugs; ethanol, lithium, retinoic acid, caffeine and thalidomide, which is known to be highly species specific. Our results point to the potency of specific teratogens and their affected tissues and pathways. Specifically, we could show that ethanol caused dramatic increase in endodermal differentiation, retinoic acid caused misregulation of neural development, and thalidomide affected both these processes. We thus propose this method as a valuable addition to currently available animal screening approaches."
			* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' <ref>Lim JH, Kim SH, Shin IS, Park NH, Moon C, Kang SS, Kim SH, Park SC, Kim JC. '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' Birth Defects Res (Part B) 92:69-76, 2011. [http://www.ncbi.nlm.nih.gov/pubmed/21254368 PMID:21254368]</ref> "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."
	\|}		\|}

	~~Birth Defects Res B Dev Reprod Toxicol. 2011 Feb;92(1):69-76. doi: 10.1002/bdrb.20283. Epub 2011 Jan 19.~~
	* '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' <ref>Lim JH, Kim SH, Shin IS, Park NH, Moon C, Kang SS, Kim SH, Park SC, Kim JC. '''Maternal exposure to multi-wall carbon nanotubes does not induce embryo-fetal developmental toxicity in rats.''' Birth Defects Res (Part B) 92:69-76, 2011. [http://www.ncbi.nlm.nih.gov/pubmed/21254368 PMID:21254368]</ref> "The results show that repeated oral doses of multi-wall CNTs (MWCNTs) during pregnancy induces minimal maternal toxicity and no embryo-fetal toxicity at 1,000 mg/kg/day in rats. The no-observed-adverse-effect level of MWCNTs is considered to be 200 mg/kg/day for dams and 1,000 mg/kg/day for embryo-fetal development. In this study, the dosing formulation was not analyzed to determine the degree of reaggregation (or not), nor were blood levels of CNT's measured in the dosed animals to verify or characterize absorption."

	==Critical Periods of Development==		==Critical Periods of Development==

Z8600021 at 23:56, 12 November 2014

2014-11-12T23:56:11Z

← Older revision		Revision as of 09:56, 13 November 2014
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	How and why do things go wrong in development? Embryological development is a robust biological system able to cope with many stresses without long-term consequences. When development does go wrong there are generally 3 major types groups: Genetic (inherited), Environmental (maternal) derived and Unknown (not determined or known) abnormalities. Also often not considered, is that pregnancy itself can also expose abnormalities in the mother (congenital heart disease, diabetes, reproductive disorders) that until the pregnancy had gone undetected.		How and why do things go wrong in development? Embryological development is a robust biological system able to cope with many stresses without long-term consequences. When development does go wrong there are generally 3 major types groups: Genetic (inherited), Environmental (maternal) derived and Unknown (not determined or known) abnormalities. Also often not considered, is that pregnancy itself can also expose abnormalities in the mother (congenital heart disease, diabetes, reproductive disorders) that until the pregnancy had gone undetected.

	* '''Infections'''		* '''Infections''' collectively grouped under the acronym [[Abnormal Development - TORCH Infections\|TORCH]] for Toxoplasmosis, Other organisms (parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus) , Rubella, Cytomegalovirus and Hepatitis. See also the related topics on '''maternal hyperthermia''' and bacterial infections.
	** collectively grouped under the acronym TORCH for Toxoplasmosis, Other organisms (parvovirus, HIV, Epstein-Barr, herpes 6 and 8, varicella, syphilis, enterovirus) , Rubella, Cytomegalovirus and Hepatitis. See also the related topics on '''maternal hyperthermia''' and bacterial infections.

	* '''Maternal diet''' the best characterised is the role of low folic acid and Neural Tube Defects (NTDs) see also abnormal neural development and Neural Tube Defects (NTDs). More recently the focus has been on dietary iodine levels and the role they also play on neural development.		* '''Maternal diet''' the best characterised is the role of [[Abnormal Development - Folic Acid and Neural Tube Defects\|low folic acid]] and Neural Tube Defects (NTDs) see also abnormal neural development and Neural Tube Defects (NTDs). More recently the focus has been on [[Abnormal Development - Iodine Deficiency\|dietary iodine]] levels and the role they also play on neural development.

	* '''Maternal drugs''' effects either prescription drugs (therapeutic chemicals/agents, thalidomide limb development), non-prescription drugs (smoking), and illegal drugs (Cannabis/Marijuana, Methamphetamine/Amphetamine, Cocaine, Heroin, Lysergic Acid Diethylamide)		* '''Maternal drugs''' effects either prescription drugs (therapeutic chemicals/agents, thalidomide limb development), non-prescription drugs (smoking), and illegal drugs (Cannabis/Marijuana, Methamphetamine/Amphetamine, Cocaine, Heroin, Lysergic Acid Diethylamide)

	* '''Environment''' (smoking, chemicals, heavy metals, radiation) and maternal endocrine function (maternal diabetes, thyroid development) and maternal stress.		* '''Environment''' ([[Abnormal_Development_-_Smoking\|smoking]], [[Abnormal Development - Chemicals\|chemicals]], [[Abnormal Development - Heavy Metals\|heavy metals]], radiation) and maternal endocrine function (maternal diabetes, thyroid development) and maternal stress.

	* '''Teratogen synergism''', different environmental effects can act individually or in combination on the same developing system. For example, neural development can be impacted upon by alcohol (fetal alcohol syndrome), viral infection (rubella) and/or inadequate dietry folate intake (neural tube defects). These effects may also not be seen as a direct effect on a system or systems but result in a reduced birth weight and the potential postnatal developmental effects. Consider also this in relation to the increasing support to the '''fetal origins hypothesis'''.		* '''Teratogen synergism''', different environmental effects can act individually or in combination on the same developing system. For example, neural development can be impacted upon by alcohol (fetal alcohol syndrome), viral infection (rubella) and/or inadequate dietry folate intake (neural tube defects). These effects may also not be seen as a direct effect on a system or systems but result in a reduced birth weight and the potential postnatal developmental effects. Consider also this in relation to the increasing support to the '''fetal origins hypothesis'''.