Effects of Drugs Taken During Pregnancy

Disclaimer: We acknowledge that not all pregnant females will remain the mother of the child and that not all mothers may have biologically given birth to their child. In this article, we use the term "mother" for the sake of simplicity and consistency.

Expecting mothers and fathers often feel worried about whether or not their child will be healthy. Some of the major factors currently posing a threat to bearing a healthy child include exposure to chemicals and radiation at home or work, exposure to infectious diseases, and use of cigarettes and other drugs during pregnancy. Various types of medications and drugs can have serious and potentially lethal effects on the development of a fetus. Teratology, the study of the causative factors of birth defects, has provided a great deal of information regarding the effects of drugs taken during pregnancy on a developing baby.1 In the United States, about 150,000 babies are born each year with birth defects, totaling about 3% of all children born.2

Females who use drugs, such as alcohol and tobacco, while pregnant are at an increased risk for complications during pregnancy and after childbirth. These complications may include premature labor, miscarriage, or developmental disorders.1 The greater that the doses and frequency of drug use are, the greater the likelihood and severity of possible complications becomes. The timing within the period of pregnancy also influences the effects of fetal damage related to drug use. For example, between 4 and 8 weeks after conception, drugs and alcohol are more likely to increase the risk of spontaneous abortions or physical deformations as compared to the late stages of fetal development and pregnancy.1 Consuming harmful chemicals after the eighth month of gestation is often associated with retarded growth, prematurity, low birth weight, and neurological damage. Any drug taken is capable of reaching a developing baby through the placenta, so any drug that affects the mother also affects the developing baby.

One of the greatest risks posed to a developing baby is the possibility of an overdose, as even small amounts of some drugs can be overwhelming for the developing baby’s liver. Additionally, certain drugs alter natural hormonal and metabolic processes, affecting how the placenta functions and how the baby develops.1 This article explores the specific effects of some major drugs that may be taken during pregnancy.


Drinking alcohol while pregnant can have serious effects on a developing baby. Fetal alcohol spectrum disorders (FASDs) are a collection of conditions that may develop in a baby whose mother consumed alcohol during pregnancy. These conditions can include learning disabilities, behavioral problems, and physical deformations.3 After drinking alcohol, it is passed from mother to developing baby through the umbilical cord and placenta, so any amount consumed by the mother will reach the developing baby as well. However, there has been some opposition to practicing complete abstinence from alcohol while pregnant, as some sources claim consuming small amounts of alcohol is actually safe. These claims are not well-supported, and the only safe amount of alcohol for a female to consume while pregnant is none. The U.S. Surgeon General, the Centers for Disease Control and Prevention (CDC), and other reputable sources assert that there is no safe amount of alcohol for a female trying to become pregnant, may become pregnant on accident, or is already pregnant.4

At no time during the entire pregnancy are the effects of alcohol completely mitigated. All alcoholic beverages are capable of causing fetal alcohol spectrum disorders, including hard liquor, wine, and beer. For females who have already been consuming alcohol during pregnancy, stopping immediately is the best way to prevent any future damage or risk of FASDs. A developing baby’s brain continues to grow throughout the entire gestation period, so the sooner a female stops, the better for all involved.

There are many possible signs and symptoms of FASDs, as the term reflects a wide range of conditions that affect a developing baby if alcohol is consumed during pregnancy. Each condition can change in severity depending on the individual. Some consequences of FASD include the following:

  • Abnormal facial features, such as cleft palate or cleft lip
  • Low birth weight
  • Underdeveloped head size
  • Stunted growth and height
  • Coordination problems
  • Behavioral problems, such as poor attention or hyperactivity
  • Learning disabilities, especially in math
  • Communication delays, such as with comprehension, speech, and language
  • Reduced judgment and reasoning ability
  • Nursing and sleeping issues
  • Impairment of the senses, such as vision and hearing
  • Complications with the heart, liver, and other internal organs3

There are various terms used to describe different types of FASDs depending on the symptoms observed. Fetal alcohol syndrome (FAS) is the broadest part of the spectrum, with the most extreme case being the death of the developing baby. Babies with FAS may show abnormal facial features, nervous system problems, and slow growth. Those with FAS may also encounter problems with the senses and cognitive functions. Another variant of FASDs is alcohol-related neurodevelopmental disorder (ARND), in which patients encounter intellectual disabilities, such as problems with learning, math, judgment, attention, and impulse control. A third variant of FASDs is alcohol-related birth defects (ARBD). Patients with ARBD typically experience problems related to their heart, kidney, bones, senses, or any combination.3

Fetal alcohol syndrome disorders cannot be cured and last throughout a person’s life. Only by taking preventative measures, such as complete abstinence from alcohol, can the likelihood of improper development be reduced. Many treatment options are available to help with symptoms, but complications may arise since there is no generalizable treatment for every child afflicted with FASDs. Individualized approaches are necessary for treatment.3

Amphetamine (Adderall)

Females who are managing attention deficit hyperactivity disorder (ADHD) often use the brand name drug called Adderall to treat their symptoms. The drug increases dopamine and norepinephrine levels in the brain which allow for better focus and impulse control.5 Adderall is not recommended for use in pregnant females. Considering the potential harm to females and developing babies, studies are mostly limited or report negative side effects in using Adderall during pregnancy, however animal testing has produced results of birth defects and miscarriage. The additional effects of increasing a person’s blood pressure and heart rate with Adderall are also reasons why use of this drug is discouraged during pregnancy and why one should abstain from use.5 Expecting mothers should work with their doctors to find healthy alternatives for managing ADHD during pregnancy to ensure the safety of themselves and their developing babies.


During pregnancy, it is possible to catch a bacterial infection, and antibiotics may be needed. While some medications have been determined safe to take during a female’s pregnancy, others are not safe and have the potential to cause birth abnormalities.6 In order to help patients understand and differentiate this wide range of medications, the U.S. Food and Drug Administration (FDA) created a list of Pharmaceutical Pregnancy Categories to help patients understand the risks of individual antibiotics. The antibiotics are assigned into categories labelled A, B, C, D, and X.  Antibiotics in the A category, which include amoxicillin, ampicillin, clindamycin, erythromycin, and penicillin, are typically the most safe to use during pregnancy. Conversely, on the opposite side of the spectrum, the X category of antibiotics includes drugs that should never be used while pregnant. Examples of the X category are doxycycline and minocycline. Potential birth defects from antibiotics include physical deformations of the head and face, problems with breathing and movement, and problems with the heart.6 All expecting mothers should consult a doctor before adding or continuing any antibiotics once pregnancy occurs.


Treating depression remains important during pregnancy in order to maintain optimal care for a female and her developing baby. Current data shows low risks for birth defects and other complications from mothers taking antidepressants while pregnant.7 One type or antidepressant, selective serotonin reuptake inhibitors (SSRIs) are generally acceptable for use and include citalopram (Celexa), fluoxetine (Prozac), and sertraline (Zoloft). Paroxetine (Paxil) however, another SSRI, is strongly discouraged due to a possible link with fetal heart defects.7

Another alternative, serotonin and norepinephrine reuptake inhibitors (SNRIs) are seem as generally acceptable and include duloxetine (Cymbalta). Other generally safe antidepressants include bupropion and tricyclic antidepressants.7 Some antidepressants that pose potential threats and should be avoided include monoamine oxidase inhibitors (MAOIs) such as phenelzine (Nardil) and tranylcypromine (Parnate) due to effects of slowing fetal growth. Although the potential risks are low for the safer antidepressants, it is still important for a pregnant female to consult her doctor about the best options for the health of herself and the developing baby. A female should never remove or change medications without consulting a medical professional.



Caffeine use is also limited in studies on its effects on a developing baby. Caffeine is a stimulant and a diuretic, which can lead to dehydration and increased blood pressure, effects that are not healthy for a female her developing baby.8 Caffeine crosses the placenta and has to be metabolized by the baby, which is hard to do at early stages of development. Caffeine may cause irregular movements and sleep patterns as the baby is stimulated by the drug.8 There are mixed studies on caffeine having effects on birth defects, miscarriages, and delayed conception. There is not enough evidence to support neutral or negative claims. Overall, it is safest for caffeine to be avoided or strictly moderated to an amount equal to about one cup of coffee per day.


Cocaine (Crack)

Cocaine, commonly known as coke or blow, is another drug that poses dangers to a mother and her developing baby. For the user, cocaine affects the central nervous system and can cause altered senses, nausea, tremors, paranoia, and emotional swings.9 Cocaine, like any other drug, is able to be passed to a developing baby through the placenta and yields many potential adverse effects including the following:

  • Early placental separation from the uterus causing bleeding and potential death for the developing baby and mother
  • Premature birth
  • Low birth weight
  • Miscarriage
  • Neonatal abstinence syndrome, in which a baby is born addicted to a drug and goes through withdrawal symptoms

All of the listed adverse effects can be avoided by abstaining from the use of cocaine. When cocaine is in the form of crack, the potential harm remains the same and should also be avoided entirely.9


Cold, Pain, and Allergy Medications (Over-the-Counter)

Suffering from a cold, pain, or allergies is never easy, especially while undergoing a pregnancy.
For the safety of a mother and her developing baby, it is important to know which over-the-counter medications for the common cold, pain, and allergies are safe to use during pregnancy. Common medications that should be avoided include ibuprofen (Advil), aspirin, and herbal remedies.10 Herbal remedies tend to be unregulated so potential risks are unknown. Medications that are known to be safer for use during pregnancy includes acetaminophen (Tylenol), diphenhydramine (DPH or Benadryl), pseudophedrine (Sudafed), and loratadine (Claritin).10 Doctors recommend products that contain as few chemicals or ingredients as possible to minimize all risks.10 Additionally, even if a female believes a product to be safe for use during pregnancy, the best option is to consult a doctor for options.

Corticosteroids (Steroids)

A special “drug” case to consider is that of corticosteroids. Normal gestation lasts approximately 35 to 40 weeks from the day of conception; however, there is a possibility that a mother can go into labor earlier than expected. Receiving corticosteroid injections may help boost lung function for babies born early (approximately between 29 to 34 weeks) increasing the baby’s chances of survival by up to 40%.11 The period between two and seven days of birth shows the greatest boosts in babies’ health after corticosteroid injections. Other benefits may include reduced chances of brain hemorrhaging and intestinal problems.11

The risks associated with corticosteroids are mitigated when use is limited to a single injection. Side effects only tend to occur if steroids were introduced at very high doses or early in the pregnancy.11 Mothers should constantly consult their doctors to determine the best options for themselves and their babies.

Marijuana (Cannabis)

Research on the effects of marijuana usage during pregnancy is limited, yet there are still some noteworthy observations to address. A large study conducted on over 12,000 females did not find statistical correlation between birth defects and marijuana use.12 Conversely, other studies conducted report associations between a pregnant female’s marijuana use and the birth weight of a baby. Prenatal exposure to marijuana has been linked to decreased in utero development (or development while the baby is still in the mother’s uterus). Frequent users may put their developing baby at the risk of slow fetal growth or premature birth.12 Other studies indicate possible ties between marijuana use and neurological development, such as in some cases where babies show unusual responses to visual stimuli, crying, and shaking.Further research suggests the possibility that prenatal exposure to marijuana can affect learning ability and emotional control in children, but more research is still needed to definitively draw conclusions.12 It remains the best advice is to abstain from marijuana use completely while pregnant, as with any other drug. If any concerns arise, one should always immediately consult a doctor.

MDMA (Ecstasy)

MDMA, otherwise known as 3,4-methylenedioxymethamphetamine or ecstasy, is a synthetic drug often used to invoke feelings of warmth, euphoria, and pleasure. Additional side effects may also include increased anxiety, lowered ability to sleep, and decreased cognitive function. For females who are pregnant, ecstasy should still be avoided because it is able to pass through a female’s placenta to the developing baby. Data collected from females who used ecstasy during their pregnancy revealed that after a four-month checkup, babies had decreased motor function along with slow and delayed movements.13 There was also a correlation found between the severity of the developmental complications and the frequency and intensity of drug use. Further research indicates that ecstasy use while pregnant promotes excessive neuron growth in the brain, which may result in a tendency towards increased stress and anxiety, decreased attention span, or hyperactivity.14


For drugs such as methamphetamine, specific knowledge about the effects on developing babies is limited due to both the number of studies and the fact that many users of hard drugs often use more than one drug.15 Available research on methamphetamine use during pregnancy indicates higher chances of premature birth, early separation of the placenta from the uterus, and abnormalities in the heart and brain. Furthermore, children born to mothers who abuse methamphetamine are at risk for neonatal abstinence syndrome (in which a baby is born addicted to the drug and goes through withdrawal symptoms) as well as problems with decreased arousal, increased stress, and decreased focus.15


Opioids and narcotics such as heroin, morphine, codeine, and methadone can also have severe effects on a developing baby. Since narcotics are passed to the developing baby through the placenta, addiction to narcotics may result in a narcotized fetus who experiences withdrawal after adjusting to use during gestation.5 Unfortunately, extreme sudden withdrawals by a pregnant female may lead to miscarriage or high fetal distress depending on the stage of the pregnancy. Treatment plans need to be developed and appropriately followed if a mother is using narcotics while pregnant to mitigate damage for the developing baby. Heroin use during pregnancy has also been linked to slow growth, low birth weight, premature birth, and even fetal death.5


Phencyclidine (PCP)

Although phencyclidine (PCP) use while pregnant has not been studied in depth, the hallucinogenic effects and violent tendencies that PCP induces can pose an immediate threat to a developing baby if the mother hurts herself. PCP use is also linked to low birth weight, damage to the brain, improper bone and muscle development, and withdrawal symptoms.16


Tobacco, usually in the form of cigarettes, is one of the most commonly abused drugs by females who use drugs during pregnancy.17 It is worth noting that females who smoke are less likely to get pregnant in the first place.However, a survey conducted in 2011 revealed that about 10% of expecting mothers reported smoking during their last three months of pregnancy.

Smoking during pregnancy has also been identified as the most preventable cause of illness and death amongst infants according to the Centers for Disease Control and Prevention (CDC). For females who smoked a minimum of three months before becoming pregnant, 55% were reported to have quit during the entire term of the pregnancy. Smoking while pregnant also increases the chances of a miscarriage. Additionally, the placenta, which is the source of a developing baby’s food and oxygen during gestation, can be damaged from smoking during pregnancy too; this damage may include separating from the womb too early, causing bleeding that is dangerous to both the mother and developing baby. Smoking during pregnancy has also been linked to premature birth in babies, as well as babies being born at an abnormally low weight, increasing the likelihood of illness or death. Birth defects, such as a cleft lip, are also possible. In the worst cases, smoking during and even after pregnancy creates risk for sudden infant death syndrome (SIDS).

Recent technological developments have led to the creation of electronic-cigarettes and vaporizers. These devices are often used to ingest nicotine through a flavored liquid heated into a breathable vapor. In general, the vapor of e-cigarettes is less harmful than cigarette smoke, however, this does not mean they are safe to use during pregnancy.17 Nicotine is still able to be passed through the placenta to the developing baby, and can cause damage to a developing baby’s brain and lungs. Additives used in the development of the vaporizing liquid may also have variable effects on developing babies. E-cigarettes and vaporizers should be avoided along with regular cigarettes and tobacco. All forms of nicotine are harmful to the development of a healthy baby, including nicotine patches and gum.

Secondhand smoke is also dangerous to developing fetuses, and has been linked to babies with low birth weights.17 Because there is no safe level of exposure to cigarette smoke, preventative measures should be taken to ensure the health of the mother and developing baby. Examples of preventative measures include prohibiting the use of cigarettes (especially when indoors such as in one’s home or car), asking known smokers to abstain around one who is pregnant, and choosing businesses that are smoke-free.

Drugs Taken During Labor

Many females opt to use pain-relieving medications during labor and delivery to reduce discomfort. Generally, there are two types of drugs used in these situations: analgesics and anesthetics. Local anesthetics affect only isolated areas of the body to alleviate pain and are usually injected around nerves connecting to the vagina and nearby areas during delivery. Regional anesthetics and analgesics can also be used to lower pain in larger regions, such as below the waist.18 Examples of analgesics include the epidural block (the most commonly used pain-reliever during labor), the  spinal block, and the combination spinal-epidural block. For all of these methods, the user still remains conscious and is able to be active in the delivery of their baby while reducing associated pain. Epidurals rarely have side effects but there is potential for decreased blood pressure, which may slow the heartbeat of the baby. Additionally, the mother may experience fever, headache, and other muscular aches.18 A spinal block differs in that a small amount of pain-reliever is injected into the spinal fluid to treat pain quickly. Potential side effects are the same as with the epidural block. The combination spinal-epidural is another option that incorporates both methods for instant and maintained pain relief.

There are also general anesthetics that can be administered with an intravenous injection or breathing mask. General anesthesia causes loss of consciousness, but patients are intubated to ensure safe and proper breathing. Potential risks include the possibility of the baby having a decreased breathing rate and lowered responses to stimuli.18 For the mother, there is a risk of accidental inhaling stomach contents, which can lead to a lung infection. In general, the risks are low for analgesics and anesthetics, but it is still important for a female to consider her options and work with her doctors to determine which options are best for her and the baby.


Drugs Taken While Breastfeeding

After the birth of a child, a mother may wonder about the possibility of drugs being passed to a newborn through her breastmilk. Studies have found that most drugs can be passed into a mother’s breastmilk; however, they must first pass through the bloodstream, meaning that only very trace amounts (often less than 1%) of the original dose make it into breastmilk. Compared to the placenta, the breast is a very effective guard protecting nursing infants from dangers of drugs.19 Most drugs that can be taken during pregnancy are safe for use during breastfeeding as well. Nevertheless, it is important to know the risks and facts to make the most informed decisions.  

One factor to consider is the way in which a drug is used. For example, topical medications are generally safe for nursing mothers; however, intravenous and intramuscular injections are able to reach breastmilk more quickly and at increased volume. The dosage and frequency of drug use can also affect levels in breastmilk. The age and health of a feeding baby should also be taken into account. The younger a baby is, the less developed its organs are including the toxin-fighting structures such as the kidneys and liver. As newborns are in a delicate state, even small amounts of drugs can have significant consequences.19 Other factors of consideration are the frequency of feedings, the amount of breastmilk consumed in a feeding, and the specific chemical composition of drugs.

The best recommendation is to only a take a drug if it is absolutely necessary, and to always consult a doctor beforehand for a professional opinion. If a drug needs to be taken while breastfeeding, the lowest possible dose is recommended, and should be timed so that the lowest amount of the drug is present in breastmilk during the next feeding. Another good idea is to monitor any reactions a feeding baby may have in case of anything irregular.

Drugs that should never be taken while breastfeeding include radioactive compounds, alcohol, caffeine, nicotine, marijuana, heroin, cocaine, methamphetamine, hallucinogens, and some prescription drugs.19 The reality is that many females will still decide to use drugs while breastfeeding. The best advice is to abstain from drug use, but if a female decides to indulge, it is important to at least weigh the risks and reward. Very small amounts of any drug consumed will reach breastmilk, and consequently, a feeding baby, so mothers should consider avoiding breastfeeding their child (despite the known benefits on breastmilk) if they cannot abstain from drug use. All drugs should be checked with a doctor before beginning or continuing use while breastfeeding.

Concluding Remarks

A developing baby is always reliant on its mother for its oxygen, nutrients, hormones, chemicals, and everything needed to develop fully and properly. Disruption by any drug to the fetal environment can pose short and long-term risks to both the child and mother. While healthcare professionals should always be consulted when situations involving drugs arise, abstinence from drugs overall is the best way to ensure the highest chances of a healthy term and birth.



1. “Facts about Birth Defects.” Centers for Disease Control and Prevention, 21 September 2015. Web. 15 April 2017.

2. “Birth Defect Statistics.”  Physicians Committee for Responsible Medicine. Web. 6 May 2017.

3. “Facts about FASDs.” Centers for Disease Control and Prevention, 16 April 2015. Web. 16 April 2017.

4. Greenberg, Jerrold S., Clint E. Bruess, and Sara B. Oswalt. Exploring the Dimensions of Human Sexuality. Burlington, Mas: Jones and Bartlett, 2014. Print. 16 April 2017.

5. “Adderall in Pregnancy: Is It Safe?” Healthline.com. 18 July 2016. Web. 8 May 2017.

6. Fetters, K. Aleisha. “Antibiotics and Pregnancy.” Parents.com. 2011. Web. 16 April 2017.

7. “Antidepressants: Safe during pregnancy?” MayoClinic.org. 3 Feb 2015. Web. 8 May 2017.

8. “Caffeine Intake During Pregnancy.” American Pregnancy.org. 2 September 2016. Web. 18 April 2017.

9. “Cocaine and Pregnancy.” MarchofDimes.org. November 2013. Web. 17 April 2017.

10. Rodriguez, Diana. “Cold Medicine and Pregnancy.” EverydayHealth.org. 27 Aug 2009. Web. 8 May 2017.

11. “How Preterm Labor Adjuctive Therapy Helps.” HealthLine.com. 15 March 2012. Web. 18 April 2017.

12. Alvarado, Sonia. “Clearing the Smoke about Marijuana Use During Pregnancy.” MothertoBaby.org. 7 February 2014. Web. 17 April 2017.

13. Pappas, Stephanie. “Ecstasy in Pregnancy is Bad for Baby, Study Finds.” LiveScience.com. 8 March 2012. Web. 8 May 2017.

14. “Effects of MDMA (Ecstasy) Use During Pregnancy.” DrugAddictionTreatment.com. 18 May 2013. Web. 8 May 2017.

15. “What are the risks of methamphetamine abuse during pregnancy?” DrugAbuse.gov. September 2013. Web. 18 April 2017.

16. “Using Illegal Drugs During Pregnancy.” AmericanPregnancy.org. July 2015. Web. 18 April 2017.

17. “Tobacco Use and Pregnancy.” Centers for Disease Control and Prevention, 20 July 2016. Web. 15 April 2017.

18. “Medications for Pain Relief During Labor and Delivery.” ACOG.org. March 2014. Web. 10 May 2017.

19. Smith, Anne. “Drugs and Breastfeeding.” BreastfeedingBasics.com. September 2015. Web. 10 May 2017.


Last Updated: 4 June 2017.