'Maternal Buprenorphine Affects Fetal Breathing'

 Measures of fetal breathing movement were lower in fetuses of pregnant patients who received buprenorphine, compared with controls, based on data from 177 individuals.

The findings were presented at the annual clinical and scientific meeting of the American College of Obstetricians and Gynecologists by Caroline Bulger, MD, of East Tennessee State University, Johnson City.

Pregnant patients with opioid-use disorder in the community surrounding Johnson City receive medication-assisted therapy with buprenorphine during the prenatal period, Dr Bulger and colleagues wrote in their abstract. The current prenatal program for substance use disorder was established in 2016 based on patient requests for assistance in lowering their buprenorphine dosages during pregnancy, said senior author Martin E. Olsen, MD, also of East Tennessee State University, in an interview.

"Buprenorphine medication–assisted treatment in pregnancy is associated with long-term effects on childhood development such as smaller neonatal brains, decreased school performance, and low birth weight"; however, data on the fetal effects of buprenorphine are limited, said Dr Olsen.

The current study was conducted to evaluate a short-term finding of the fetal effects of buprenorphine, Dr Olsen said.

"This study was performed after obstetric sonographers at our institution noted that biophysical profile [BPP] ultrasound assessments of the fetuses of mothers on buprenorphine took longer than for other patients," said Dr Olsen.

The researchers conducted a retrospective chart review of 131 patients who received buprenorphine and 46 who were followed for chronic hypertension and served as high-risk controls. Patients were seen at a single institution between July 1, 2016, and June 30, 2020.

The researchers hypothesized that BPP of fetuses in patients receiving buprenorphine might be different from controls because of the effects of buprenorphine.

Overall, patients who received buprenorphine were more likely to have a fetal breathing score of zero than those who underwent a BPP for hypertension. A significant relationship emerged between buprenorphine dosage and breathing motion assessment; patients on high-dose buprenorphine were more likely than patients on low doses to have values of zero on fetal breathing motion assessment, and a chi-squared test yielded a P value of .04269.

The takeaway for clinical practice is that clinicians performing BPP ultrasounds on buprenorphine-exposed fetuses can expect that these assessments may take longer on average than assessments of other high-risk patients, said Dr Olsen. "Additional assessment after a low BPP score is still indicated for these fetuses just as in other high-risk pregnancies," he said.

The study was limited primarily by the retrospective design, Dr Olsen said.

Although current treatment guidelines do not emphasize the effects of maternal buprenorphine use on fetal development, these findings support previous research showing effects of buprenorphine on fetal brain structure, the researchers wrote in their abstract. Looking ahead, "We recommend additional study on the maternal buprenorphine medication–assisted treatment dose effects for fetal and neonatal development with attention to such factors as head circumference, birth weight, achievement of developmental milestones, and school performance," Dr Olsen said.

"We and others have shown that the lowest effective dose of buprenorphine can lower neonatal abstinence syndrome/neonatal opioid withdrawal syndrome rates," but data showing an impact of lowest effective dose management on long-term complications of fetal buprenorphine exposure are lacking, he noted.

The study received no outside funding. The researchers had no financial conflicts to disclose.

https://www.medscape.com/s/viewarticle/maternal-buprenorphine-affects-fetal-breathing-2024a1000a2g