Health carers must make sure pregnant women taking methadone, a treatment for heroin addiction, avoid other illicit drugs, a Swiss study suggests. Evidence indicates that around 80% of mums-to-be on methadone still take other drugs.
BBC News reports that the researchers found the combinations of methadone and heroin or cocaine made the placenta more permeable.
In pregnancy, if drugs like cocaine or heroin are used consistently, problems can include restricted growth, premature birth and miscarriage.
Methadone in pregnancy can see birth weight increase and a woman’s pregnancy continue closer to full-term. But there are problems with methadone, such as the baby suffering withdrawal symptoms after birth.
Using placentas from healthy mums, the researchers from the University of Zurich tested methadone on its own and methadone with heroin or cocaine.
Methadone by itself reduced the amount of a test chemical that was able to get through the placenta. When cocaine or heroin was added to the methadone, the amount of the chemical that permeated the placenta increased.
The study did not look at what cocaine or heroin did to the placenta when used in isolation.