Teratogen: a substance capable of interfering with fetal development Teratology: the biological...

Post on 12-Jan-2016

215 views 1 download

Tags:

Transcript of Teratogen: a substance capable of interfering with fetal development Teratology: the biological...

Teratogen: a substance capable of interfering with fetal development

Teratology: the biological study of birth defects

Toxicology: the science of dealing with the effects and detection of poisons

Foolish, drunken, or harebrain women most often bring forth children like unto themselves Aristotle in Problemata

Behold, thou shalt conceive and bear a son: And now, drink no wine or strong drink.

Judges 13:7

Rosett, 1984

Fetal alcohol syndrome

• Term first used in 1973 by Drs. Smith and Jones

• A medical diagnosis (760.71) in the International Classification of Diseases (ICD)

http://www.aafp.org/afp/20050715/279.html

Fetal alcohol syndrome

Fetal alcohol effects Clinical suspect but

appear normal Normal, but never

reach their potential

Adapted from Streissguth

Umbrella term describing the range of effects that can occur in an individual whose mother drank alcohol during pregnancy

May include physical, mental, behavioral, and/orlearning disabilities with possible lifelongimplications

Not a diagnosis

Pregnancy

+

Alcohol

May result in

• Alcohol-related neurodevelopmental disorder (ARND)

• Partial FAS (pFAS)

• Fetal alcohol effects (FAE)

• Alcohol-related birth defects (ARBD)

• Static encephalopathy (an unchanging injury to the brain)

No one knows for certain how many individuals are born each year with an FASD – estimates of 6/1000.

No one knows how many individuals are living with an FASD.

Photo property of SAMHSA.

The sole cause of FASD is women drinking alcoholic beverages during pregnancy

Alcohol is a teratogen

“Of all the substances of abuse (including cocaine, heroin, and marijuana), alcohol produces by far the most serious neurobehavioral effects in the fetus.”

—IOM Report to Congress, 1996

.

FASDs are the leading known cause of preventable mental retardation.

FASDs effect an estimated 40,000 newborns each year in the United States.

FASDs are more common than autism. The effects of FASDs last a lifetime. People with an FASD can grow, improve, and

function well in life with proper support.

FASDs are 100% preventable.

FSIQ VIQ PIQ

40

55

70

85

100

115

Sta

nd

ard

score

IQ scale

NC

PEA

FAS*

**

**

**

Mattson, S.N., 1997.

2

1

3

1

2

3

Group0

2

4

6

Ru

le V

iola

tion

s NC

PEA

FAS

P<0.001

Move only one piece at a time using one hand and never

place a big piece on top of a little piece

Starting position

Ending positionMattson, et al.,

1999

photo: Clarren, 1986

***

**

Cerebrum Cerebellum

75

80

85

90

95

100

PEA

FAS <p 0.001

p < 0.010

Cerebrum

CerebellumCorpus Callosum

Mattson et al., 1994

Mattson, et al., 1994; Mattson & Riley, 1995; Riley et al., 1995

Lower IQ

Impaired ability in reading, spelling, and arithmetic

Lower level of adaptive functioning

hyperactivity, response inhibition deficits, attentional problems, motor coordination deficits, executive function (planning) problems,

Poor judgement Attention deficits Arithmetic

disabilities

Memory deficits

Problems with abstract thought

Impulsivity

Easily victimized unfocused or

distractible difficulty handling $$ difficulty learning from

experience difficulty under-

standing consequences poor frustration

tolerance

= Age 6+ = Age 12+ = Age 21+

Percent of Persons With FAS or FAE Who Had Secondary Disabilities

• Show many similar characteristics to human studies.

Courtesy: Ed Riley

mammals◦ rodents (rats, mice, guinea pigs)◦ pig◦ sheep◦ primates

nonmammalian models◦ chicks◦ round worm◦ zebra fish◦ fruit flies

Growth retardation Facial

characteristics Heart, skeletal

defects Microcephaly Similar CNS deficits

Hyperactivity, attentional problems

Inhibitory deficits Impaired learning Perseveration errors Feeding difficulties Gait anomalies

Driscoll, et al., 1990; Samson, 1986;