Neonatal Abstinence Syndrome

Baby is crying in a hospital

Neonatal abstinence syndrome, abbreviated “NAS,” refers to a condition in which a newborn baby goes through withdrawal symptoms upon birth. Most cases of NAS have to do with an infant born to a mother who is addicted to opioids, hence the baby’s withdrawal off of opioids shortly after birth. (Drugs that the mother uses while pregnant are passed into the fetus via the placenta). Neonatal abstinence syndrome can also occur when a baby is born to a mother who uses alcohol, barbiturates, or benzodiazepines.

According to the National Institute on Drug Abuse, “Smoking tobacco or marijuana, taking prescription pain relievers, or using illegal drugs during pregnancy is associated with double or even triple the risk of stillbirth.” And while there’s no way to predict with certainty if a baby will be stillborn as a result of NAS, NIDA research indicates that the type and severity of an infant’s NAS symptoms depend on the drugs the mother used, how long and how often she used the drugs for, how her body breaks down the drug chemicals, and whether the infant was born full-term or prematurely.

Risks Associated with Substance Use During Pregnancy

The list of risks, harmful effects, and adverse consequences of substance abuse during pregnancy is a long one. And the list of drugs that can cause harm if used during pregnancy is also a long one. According to NIDA, drugs that can negatively affect a fetus include:

  • Marijuana
  • Stimulants (Cocaine, Methamphetamine)
  • MDMA (Ecstasy, Molly)
  • Heroin
  • Prescription pain relievers
  • Barbiturates
  • Benzodiazepines
  • Alcohol
  • Nicotine
  • Heroin

The most concerning risk associated with drug abuse during pregnancy is that a stillbirth will occur. According to NIDA research, marijuana use during pregnancy increases risks for stillbirth by 2.3x. Tobacco use increases risks for stillbirth by 1.8x to 2.8x, pain reliever use increases risk by 2.2x, and exposure to second-hand tobacco smoke increases risk by 2.1x.

Crying pregnant woman at the doctor

Infants born to mothers who drank alcohol or smoked beyond the first trimester of pregnancy are also at higher risk of Sudden Infant Death Syndrome. Such infants are twelve times more likely to experience sudden infant death syndrome than infants born to mothers who abstain from alcohol and tobacco beyond the first trimester.

Beyond stillbirths and sudden infant death syndrome, other harms and symptoms associated with NAS include:

  • Blotchy skin coloring
  • Diarrhea
  • Excessive or high-pitched crying
  • Abnormal sucking reflex
  • Fever
  • Hyperactive reflexes
  • Increased muscle tone
  • Irritability
  • Poor feeding
  • Rapid breathing
  • Seizures
  • Sleep problems
  • Slow weight gain
  • Stuffy nose and sneezing
  • Sweating
  • Trembling
  • Vomiting
  • Congenital disabilities
  • Low birth weight
  • Premature birth
  • Small head circumference

Is NAS the Same Thing as a Baby Being Born Addicted to Drugs?

Woman addict with a baby

No, and it’s harmful to think of NAS as such. Sometimes, women are harshly criticized for being addicted to drugs while pregnant. This leads to false ideas like “babies born addicted to drugs.” Concepts and conjectures like these are not only erroneous; they only serve to stereotype the mother, never actually helping the mother or her child.

Babies born to mothers who have drug problems are not born addicted, but they are born with drugs in their system. That can cause babies a great deal of discomfort in the form of withdrawal symptoms. The best and safest solution to addressing the issue is to ensure that women receive effective treatment for drug addiction before they get pregnant.

Drug Abuse During Breastfeeding is Also Harmful

One of the issues surrounding the harm of drug abuse on the unborn is that these risk factors do not end when the infant is born. If a mother uses drugs or drinks alcohol while breastfeeding, the infant continues to be exposed to those substances.

While this is not mentioned here to discourage new mothers from breastfeeding, it should serve as a reminder that the sooner a woman who is addicted to drugs can receive help, the better. Ideally, no young person would be exposed to drugs, alcohol, or tobacco, not as a fetus, infant, or child.

Long Term Effects of NAS

Given the complexities of co-occurring factors in a young person’s life, it is next to impossible to determine if a child exposed to drugs in the uterus will have health complications or psychological, behavioral struggles. As one group of researchers put it, “Determining long-term outcomes for drug-exposed babies beyond childhood is difficult because most of these children, apart from withdrawal or intoxication, are healthy. Many may also have unstable home lives resulting in frequent shifts between multiple careers, homes, and schools, making them difficult to locate for any protracted time. Also, most mothers use multiple drugs, have multiple environmental, psychiatric, and lifestyle co-morbidities and stressors that make isolating any specific long-term outcomes to a single drug exceedingly difficult.” While one can imagine that there could be long-term harm from being exposed to drug chemicals, alcohol, or nicotine during prenatal development, determining or predicting such harm is still an ongoing research effort.

While it is next to impossible to predict if a baby born with NAS will experience long-term harm, there is an awareness that long-term harm does occur. As another group of researchers put it, “In utero exposures to drugs can have long-lasting implications for brain structure and function. These effects on the developing nervous system often differ ... from their effects on mature systems [adults].”

Woman seeing doctor

The Importance of Treatment

From the increased risk factors for stillbirths and sudden infant death syndrome to the acute harm of NAS withdrawals and the potential for long term consequences, all of the risk factors that come with mothers who use drugs, alcohol, and tobacco while pregnant and breastfeeding point to a clear answer. New mothers and women who want to become mothers must seek help for drug and alcohol addiction as soon as possible.

Ideally, a woman struggling with drug and alcohol addiction would seek treatment before she gets pregnant. But the critical factor is that she does get treatment. Her family members, loved ones, friends, coworkers, and community members should help her get into a treatment center as soon as possible. They should not stereotype, stigmatize, or condemn her for her addiction.


Reviewed by Claire Pinelli, ICAADC, CCS, LADC, RAS, MCAP, LCDC


Karen Hadley

For more than a decade, Karen has been researching and writing about drug trafficking, drug abuse, addiction and recovery. She has also studied and written about policy issues related to drug treatment.