There are many medications and drugs that can have serious effects on a fetus' development. During gestation, almost all drugs cross the placenta and affect the unborn child. It is clear that women who engage in consumption of many illegal and legal drugs during pregnancy are at increased risk for complications, including premature labor and delivery. They are also more likely to lose a fetus through miscarriages and stillbirths than are women who abstain from drugs. The greater the extent of the drug-use, the more likely there will be adverse consequences. The timing of drug use during a pregnancy related to types of consequences. For example from the fourth to the eighth week following conception, drug use is more likely to increase the risk of spontaneous abortions and physical malformations of the newborn than is drug use later on in pregnancy. Use of drugs after the eighth month of pregnancy is often associated with retarded growth, prematurity, low birth weight, and neurological damage. Pregnant women should take extra precautions to avoid using such substances. Drugs and medications that should be avoided are discussed in detail below.
Antibiotics
Long-term use of prescription antibiotics may cause damage to a developing fetus. Nitrofurantoin may cause jaundice. The acne medicine, Accutane, may cause severe birth defects if taken during pregnancy. Tetracycline may cause stained teeth and bone deformities. Gentamycin, kanamycin, neomycin, streptomycin, and vancomycin all may cause deafness. Various fetal abnormalities may result from taking some drugs prescribed for diabetics (Hyde and DeLamater, p.157).
Alcohol
Alcohol consumed by a pregnant woman is absorbed by the placenta and directly affects the fetus (Hyde and DeLamater, p.158). A variety of malformations and disorders occur due to alcohol use during pregnancy. These defects are collectively called Fetal Alcohol Syndrome (FAS). Some characteristics of Fetal Alcohol Syndrome are mental retardation; both prenatal and postnatal growth deficiencies; small eye openings; a small brain; and joint, limb, and heart malformations (Hyde and DeLamater, p.158). Alcohol consumption during pregnancy is detrimental to a fetus' health. Please abstain from drinking any amount of alcohol during pregnancy.
Cocaine
Cocaine use during pregnancy may result in a premature birth (Handler et al., 1991) and low birth weight (Phibbs et al., 1991). The only physical effect that has been regularly associated with cocaine use is a smaller head circumference (Cherukuri et al., 1988). This implies that cocaine-exposed children are more likely to be microcephalic, which is associated with poor growth and low intelligence-test scores. Neurological deficits and central nervous system abnormalities have been reported in infants exposed to cocaine in utero (O'Shea, 1995). It is also reported that children are more irritable at 3 to 6 months of age. At 18 months, they have difficulty focusing their attention; more behavioral problems are evident in such children (Vogel, 1997).
Steroids
Synthetic hormones such as progestin can cause a female fetus to be masculinized (Hyde and DeLamater, 158). Some, but not all studies show that corticosteroids are linked with low birth weight, stillbirth, and cleft palate (Ostensen, 1994). Large amounts of vitamin A are associated with cleft palate. Eccessive amounts of vitamin D, B6, and K have been linked with fetal defects. Diethylstilbestrol (DES), a potent estrogen, has been shown to "cause cancer in the vagina in girls whose mothers took the drug while pregnant" (Herbst, 1972). An increased risk of low birth weight is associated with long-term exposure to DES (Zhang and Bracken, 1995).
Other drugs
The U.S. Public Health Service claims that maternal cigarette smoking causes low birth weight, increased incidence of premature birth, and retarded fetal growth. Some antihistamines may cause malformations in a fetus. Even common medications like aspirin may cause blood problems in a developing fetus (Cunningham et al., 1989).
The psychoactive chemical in marijuana is able to cross the placental barrier (Harbison and Mantilla-Plata, 1972; Idanpaan-Heikkila et al., 1969). Some evidence shows that marijuana inhibits ovulation (Abel, 1984); thus using marijuana may make conception more difficult. A Canadian study compared pregnant women who used marijuana with pregnant nonusers. According to the study, there were no differences between the two groups in terms of miscarriage, complications during birth, or incidence of birth defects. However, the infants of the marijuana users had more tremors and more visual problems during their preschool years (Fried, 1986). Lower scores on intelligence tests and poor task performance have also been reported in six-year-olds who had been exposed to marijuana in utero (Day and Richardson, 1994).
Although X-rays are not considered a drug, they can damage the fetus. Risk of damage is particularly high during the first 42 days after conception (Hyde and DeLamater, p.159).
Dads and drugs
Little research has been done on the effects of a man's drug use on a fetus. However, drugs taken by men before conception may cause birth defects because some drugs can damage the sperm and their genetic contents (Narod et al., 1988). Studies have shown that an increase risk of childhood cancer occurs when a father smokes cigarettes even when the mother does not (John et al., 1991). Hopefully future research will clarify any other effects of a father's use of drugs on his children.
© - Reproduced with permission of SexInfo, University of California at Santa Barbara, 2007.