Buprenorphine is a semi-synthetic opioid derived from the morphine alkaloid thebaine which has mixed agonist-antagonist properties. It is typically administered intramuscularly, intravenously, by sublingual tablet, or via transdermal patch. Buprenorphine is used for the treatment of moderate to severe pain and, when combined with psychological treatment, as a substitution treatment in the management of opioid dependence.
Several animal studies have found adverse fetal effects following maternal exposure to buprenorphine. The limited available data relating to use of buprenorphine during human pregnancy have not identified increased risks of congenital malformation, preterm delivery, or low infant birth weight but are likely to be confounded, and comparisons are often to cohorts of women on other opioid substitution therapies. Data on rates of intrauterine death following buprenorphine exposure do not raise concern but are too limited to state definitively that no increased risk exists. Data on the rates of spontaneous abortion and adverse neurodevelopment are too limited to allow an evidence-based risk assessment.
Use of any opioid during pregnancy, particularly around the time of delivery, confers a risk of neonatal respiratory depression. Prolonged use of opioids throughout pregnancy may result in neonatal withdrawal and this has been documented specifically in buprenorphine-exposed infants. Infants gestationally exposed to buprenorphine should therefore ideally be delivered in a unit with facilities to provide monitoring and treatment for these conditions.
Where buprenorphine overdose occurs in pregnancy, maternal toxicity is likely to be a major factor in determining risk to the fetus. If use of an antidote (e.g. naloxone) is required in the management of maternal toxicity it should not be withheld on account of pregnancy.
Exposure to buprenorphine at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy. Additional fetal monitoring may be required in pregnancies complicated by severe pain or opioid addiction on a case-by-case basis. Other risk factors may also be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments.
This is a summary of the full UKTIS monograph for health care professionals and should not be used in isolation. The full UKTIS monograph and access to any hyperlinked related documents is available to NHS health care professionals who are logged in.
If you have a patient with exposure to a drug or chemical and require assistance in making a patient-specific risk assessment, please telephone UKTIS on 0344 892 0909 to discuss the case with a teratology specialist.
If you would like to report a pregnancy to UKTIS please click here to download our pregnancy reporting form. Please encourage all women to complete an online reporting form.