During which gestational period is drug transfer to the fetus more likely to happen?

Opioid use during pregnancy can affect women and their babies. Women might use opioids as prescribed, misuse prescription opioids, use illicit opioids such as heroin, or use opioids (opioid agonists and/or antagonists) as treatment for opioid use disorder. Regardless of the reason, women who use opioids during pregnancy should be aware of the possible risks as well as potential treatment options for opioid use disorder. Opioid use disorder is a medical condition that requires appropriate treatment to improve the health of  mothers and babies.

Opioids are a class of drugs used to reduce pain.

• Common prescription opioids include codeine, oxycodone, hydrocodone, and morphine.
• Fentanyl is a prescription synthetic opioid pain reliever. It can also be made illegally.
• Heroin is an illegal opioid.

What is opioid use disorder?

Opioid use disorder (OUD), sometimes referred to as opioid addiction, is a problematic pattern of opioid use that causes significant impairment or distress. It was previously classified as opioid abuse or opioid dependence in DSM-IV criteria.

What is MOUD?

Medication for Opioid Use Disorder (MOUD) refers to the use of medication to treat opioid use disorder. Methadoneexternal icon and buprenorphineexternal icon are primary therapy options for pregnant women with OUD.

Opioid Use During Pregnancy

In the most recent estimateexternal icon available, the number of women with opioid-related diagnoses documented at delivery increased by 131% from 2010 to 2017.  According to 2019 self-reported data, about 7% of women reported use of prescription opioid pain relievers during pregnancy. Of those, 1 in 5 reported misuse (defined by this survey as getting prescription opioid pain relievers from a source other than a healthcare provider or using them for a reason other than to relieve pain).

Health Outcomes From Exposure During Pregnancy

Opioid exposure during pregnancy has been linked to some poor health effects for both mothers and their babies. For mothers, OUD has been linked to maternal death;1,2 for babies, maternal OUD or long-term opioid use has been linked to poor fetal growth, preterm birth, stillbirth, and specific birth defects, and can cause neonatal abstinence syndrome (see below).3,4 The effects of prenatal opioid exposure on children over time are largely unknown. In some cases—such as the treatment of OUD during pregnancy—continued use of opioid medications during pregnancy as prescribed outweighs the risks. Women should consult their physician before stopping or changing any prescribed medication.

Neonatal Abstinence Syndrome (NAS)

Opioid use during pregnancy can lead to neonatal abstinence syndrome (NAS) in some newborns. NAS is a group of conditions that can occur when newborns withdraw from certain substances, including opioids, that they were exposed to before birth. Signs of withdrawal usually begin within 72 hours after birth and may include the following:

• Tremors (trembling)
• Irritability, including excessive or high-pitched crying
• Sleep problems
• Hyperactive reflexes
• Seizures
• Yawning, stuffy nose, or sneezing
• Poor feeding and sucking
• Vomiting
• Loose stools and dehydration
• Increased sweating

The signs a newborn might experience, and how severe the signs will be, depend on different factors. Some factors include the type and amount of substance the newborn was exposed to before birth, the last time a substance was used, whether the baby is born full-term or premature, and if the newborn was exposed to other substances (e.g., alcohol,5 tobacco,5,7 other medications5-8) before birth.

Withdrawal among newborns during the first 28 days of life due to exposure to opioids before birth is called neonatal opioid withdrawal syndrome (NOWS). NOWS occurs after long-term exposure to opioids; therefore, opioids given at the time of delivery do not cause NOWS.9 For more information about NOWS, including symptoms, treatment, and planning for discharge, read the American Academy of Pediatrics’ Clinical Report, Neonatal Opioid Withdrawal Syndromeexternal icon.

NAS is a group of conditions that can occur when newborns withdraw from certain substances, including opioids, that they were exposed to before birth. Withdrawal caused by in utero exposure to opioids during the first 28 days of life is also called neonatal opioid withdrawal syndrome (NOWS).

Birth outcomes associated with opioid use during pregnancy

Infants exposed to opioids during pregnancy might be more likely to

• Be born preterm (born before 37 weeks of pregnancy);
• Have poor fetal growth;
• Have longer hospital stays after birth;
• Be re-hospitalized within 30 days of being born; and
• Be born with birth defects.

Longer-term developmental outcomes associated with opioid use during pregnancy

There is limited information about the longer-term outcomes of children exposed to opioids prenatally, including those with or without NAS. Not all babies exposed to opioids during pregnancy experience signs of NAS, but experts are concerned that there could be long-term effects on development that aren’t obvious at birth. Results from a recent studyexternal icon suggest that children with NAS were more likely to have a developmental delay or speech or language impairment in early childhood compared to children without NAS.  It is not clear if these impacts are due to opioids specifically, other substance exposures, or other environmental influences. Findingsexternal icon about the long-term outcomes of children exposed to opioids during pregnancy are inconsistent. More research is needed to better understand the spectrum of possible outcomes related to opioid exposure during pregnancy.

Treatment for Opioid Use Disorder or Long-Term Opioid Use Before, During, and After Pregnancy

If a woman is pregnant or planning to become pregnant, the first thing she should do is talk to a healthcare provider. Creating a treatment plan for OUD or conditions treated with long-term opioid use, as well as other co-occurring health conditions, before pregnancy can help a woman increase her chances of a healthy pregnancy.

Quickly stopping opioids during pregnancy is not recommended, as it can have serious consequences, including preterm labor, fetal distress, or miscarriage. Current clinical recommendationsexternal icon for pregnant women with OUD include treatment with medication for opioid use disorder (MOUD), rather than supervised withdrawal, due to a higher likelihood of better outcomes and a reduced risk of relapse.

When making decisions about whether to begin opioid therapy for chronic pain during pregnancy, healthcare providers and patients together should carefully weigh risks and benefits. For pregnant women already receiving opioids, clinicians should access appropriate expertise if considering stopping opioids because of possible risks during pregnancy. Healthcare providers caring for pregnant women receiving opioids for pain or MOUD should arrange for delivery at a facility prepared to care for newborns with NOWS. For more information, see the Pregnant Women section in CDC’s Guideline for Prescribing Opioids for Chronic Pain.

It is important to recognize that NAS is an expected condition that can follow exposure to MOUD. A concern for NAS alone should not deter healthcare providers from prescribing MOUD. Close collaboration with the pediatric care team can help ensure that infants born to women who used opioids during pregnancy are monitored for NAS and receive appropriate treatment, as well as be referred to needed services.

Support for women in treatment for OUD is critical in the postpartum period—a time of adjustments and increased stressors—which may increase the risk for relapse and overdose events. Continued access to health care and linkage to care for substance use disorders and other co-occurring conditions is important. Women with OUD during pregnancy should continue MOUD as prescribed in the postpartum period. Learn more about treatment for opioid use disorder for women before, during, and after pregnancy.

For additional resources, visit CDC’s opioid webpages:

• Opioid Use and Pregnancy | Drug Overdose | CDC Injury Center
• Rx Awareness Treatment and Recovery
• Opioid Basics
• Pregnancy and Opioid Pain Medications (English pdf icon[PDF – 0.99 MB]] [Spanish pdf icon[PDF – 223 KB])

Find More Information

For information about the risks of specific opioid medications used during pregnancy, read MotherToBaby’s fact sheetsexternal icon. MotherToBaby experts are also available by phone or online chat to answer questions in English or Spanish. This free and confidential service is available Monday through Friday from 8 a.m. to 5 p.m. (local time). To reach MotherToBaby,

• Call 1-866-626-6847
• Chat live online via the MotherToBaby websiteexternal icon
• Send an email via the MotherToBaby websiteexternal icon

Find Treatment

• Find a Health Center for Substance Abuse Servicesexternal icon
• FindTreatment.govexternal icon
• Locator for physicians providing buprenorphine for opioid use disorderexternal icon
• Locator for programs providing methadone for opioid use disorderexternal icon

References

1. Metz TD, Rovner P, Hoffman MC, et al. Maternal deaths from suicide and overdose in Colorado, 2004–2012. Obstet Gynecol. 2016;128:1233–40.
2. Smid MC, Stone NM, Baksh L, et al. Pregnancy Associated Death in Utah: Contribution of Drug-Induced Deaths. Obstet Gynecol. 2019;133(6):1131–40.
3. Yazdy MM, Desai RJ, Brogly SB. Prescription Opioids in Pregnancy and Birth Outcomes: A Review of the Literature. J Pediatr Genet. 2015;4(2):56–70.
4. Lind JN, Interrante JD, Ailes EC, et al. Maternal Use of Opioids During Pregnancy and Congenital Malformations: A Systematic Review. Pediatrics 2017;139(6):e20164131
5. Desai RJ, Huybrechts KF, Hernandez-Diaz S, et al. Exposure to prescription opioid analgesics in utero and risk of neonatal abstinence syndrome: Population-based cohort study. BMJ 2015;350:h2102.
6. Huybrechts KF, Bateman BT, Desai RJ, et al. Risk of neonatal drug withdrawal after intrauterine co-exposure to opioids and psychotropic medications: Cohort study. BMJ 2017;358:j3326.
7. Patrick SW, Dudley J, Martin PR, et al. Prescription Opioid Epidemic and Infant Outcomes. Pediatrics 2015;135(5):842–50.
8. Sanlorenzo LA, Cooper WO, Dudley JA, et al. Increased Severity of Neonatal Abstinence Syndrome Associated with Concomitant Antenatal Opioid and Benzodiazepine Exposure. Hospital Pediatrics. 2019;9(8):1–7.
9. Patrick SW, Barfield WD, Poindexter BB, et al. Neonatal Opioid Withdrawal Syndrome. Pediatrics 2020;e2020029074.

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