Diseases


A young girl in a pink shirt sneezes.
lightwavemedia/Shutterstock
Rubella (German measles)

Effects of exposure on fetus:

In embryonic period, causes blindness and deafness; in first and second trimesters, causes brain damage.

Preventive measures:

Immunization before becoming pregnant.

Toxoplasmosis

Effects of exposure on fetus:

Brain damage, loss of vision, intellectual disabilities.

Preventive measures:

Avoid eating undercooked meat and handling cat feces, garden dirt during pregnancy.

Measles, chicken pox, influenza

Effects of exposure on fetus:

May impair brain functioning.

Preventive measures:

Immunization of all children and adults.

Syphilis

Effects of exposure on fetus:

Baby is born with syphilis, which, untreated, leads to brain and bone damage and eventual death.

Preventive measures:

Early prenatal diagnosis and treatment with antibiotics.

HIV

Effects of exposure on fetus:

Virus may be transmitted to baby. Without treatment, illness and death are likely during childhood.

Preventive measures:

Prenatal drugs and cesarean birth make HIV transmission rare.

Other STIs, including gonorrhea and chlamydia

Effects of exposure on fetus:

Not usually harmful during pregnancy but may cause blindness and infections if transmitted during birth.

Preventive measures:

Early diagnosis and treatment; if necessary, cesarean section, treatment of newborn.

Infections, including infections of urinary tract, gums, and teeth

Effects of exposure on fetus:

May cause premature labor, which increases vulnerability to brain damage.

Preventive measures:

Good, inexpensive medical care before pregnancy.

Pollutants


A factory chimney lets out smoke into the sky.
Gemenacom/Shutterstock
Lead, mercury, PCBs (polychlorinated biphenyls); dioxin; and some pesticides, herbicides, and cleaning compounds

Effects of exposure on fetus:

May cause spontaneous abortion, preterm labor, and brain damage.

Preventive measures:

May be harmless in small doses, but pregnant women should avoid exposure, such as drinking well water, eating unwashed fruits or vegetables, using chemicals, eating fish from polluted waters.

Radiation


A set of two X-ray films, one shows the front view of the chest and the other shows the side view.
Flik47/Shutterstock
Massive or repeated exposure to radiation, as in medical x-rays

Effects of exposure on fetus:

May cause small brains (microcephaly) and intellectual disabilities. Background radiation probably harmless.

Preventive measures:

Sonograms, not X-rays, during pregnancy. Pregnant women who work directly with radiation need special protection.

Social and Behavioral Factors


A young asian woman in sports wear runs in to the middle of an empty city road.
lzf/Shutterstock
Very high stress

Effects of exposure on fetus:

May cause cleft lip or cleft palate, spontaneous abortion, or preterm labor.

Preventive measures:

Adequate relaxation, rest, and sleep; reduce intensity of employment and seek help from spouse, family members, or your doctor if you face severe stress.

Malnutrition

Effects of exposure on fetus:

hen severe, interferes with conception, implantation, normal fetal development.

Preventive measures:

Eat a balanced diet, normal weight before pregnancy, gain 25–35 lbs (10–15 kg) during pregnancy.

Excessive, exhausting exercise

Effects of exposure on fetus:

Can harm fetal growth if it interferes with woman’s sleep, digestion, or nutrition.

Preventive measures:

Regular, moderate exercise is healthy. Can harm fetal growth if it interferes with woman’s sleep, digestion, or nutrition.

Medicinal Drugs


Capsules spill out of an amber-colored medicine bottle that has fallen on its side.
Maxx-Studio/Shutterstock
Lithium

Effects of exposure on fetus:

Can cause heart abnormalities.

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Tetracycline

Effects of exposure on fetus:

Can harm teeth

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Retinoic acid

Can cause limb deformities.

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Streptomycin

Effects of exposure on fetus:

Can cause deafness

Preventive measures:

EAvoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

ACE inhibitors

Effects of exposure on fetus:

Can harm digestive organs.

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Phenobarbital

Effects of exposure on fetus:

Can affect brain development.

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Thalidomide

Effects of exposure on fetus:

Can stop ear and limb formation.

Preventive measures:

Avoid all medicines, whether prescription or over-the-counter, during pregnancy unless given by a medical professional who knows recent research on teratogens.

Psychoactive Drugs


A man smokes a cigarette.
Shutterstock
Caffeine

Effects of exposure on fetus:

Normal, modest use poses no problem.

Preventive measures:

Avoid excessive use. (Note that coffee, tea, cola drinks, chocolate all contain caffeine.)

Alcohol

Effects of exposure on fetus:

May cause fetal alcohol syndrome (FAS) or fetal alcohol effects (FAE).

Preventive measures:

Stop or severely limit alcohol consumption; especially dangerous are three or more drinks a day or four or more drinks on one occasion.

Tobacco

Effects of exposure on fetus:

Reduces birthweight, increases risk of malformations of limbs and urinary tract, and may affect the baby’s lungs.

Preventive measures:

Ideally, stop smoking before pregnancy. Stopping during pregnancy also beneficial.

Marijuana

Effects of exposure on fetus:

Heavy exposure affects central nervous system; when smoked, may hinder fetal growth.

Preventive measures:

Avoid or strictly limit marijuana consumption

Heroin

Effects of exposure on fetus:

Slows fetal growth, increases prematurity. Addicted newborns need treatment to control withdrawal.

Preventive measures:

Treatment needed before pregnancy but if already pregnant, gradual withdrawal on methadone is better than continued use of heroin.

Cocaine

Effects of exposure on fetus:

Slows fetal growth, increases prematurity and then learning problems.

Preventive measures:

Stop before pregnancy; if not, babies need special medical and educational attention in their early years.

Inhaled solvents (glue or aerosol)

Effects of exposure on fetus:

May cause abnormally small head, crossed eyes, and other indications of brain damage.

Preventive measures:

Stop before becoming pregnant; damage can occur before a woman knows she is pregnant.

*The field of toxicology advances daily. Research on new substances begins with their effects on nonhuman species, which provides suggestive (though not conclusive) evidence. This activity is a primer; it is no substitute for careful consultation with a knowledgeable professional.