This is not recommended for a few reasons. In fact expert opinion suggests the opposite – pregnant women should be put on methadone as soon as possible.
During the first trimester of the pregnancy (week 0-13) going into a withdrawal state is associated with an increased chance of miscarriage.
During the third trimester (week 27-40) many mothers require more opiate support because the mom and baby get bigger. Also during this time the mother's enzymes are induced. This speeds the metabolism of many compounds including methadone and Suboxone.Our experience at BMC shows about 60% of the mom's increase their dose of medication. The same amount of mothers decrease their dose a few months after delivery.
Mothers are at a much higher risk of relapse once they are off methadone or Suboxone than while on these medications. They are also at a higher risk of relapse when they are under stress – like the stress of delivery and having a new baby at home. Given that methadone and Subutex are safe in pregnancy it makes more sense for most people to wait until a few months after the delivery when things settle down. At this point they can start a taper at a rate that will keep them comfortable and drug free. A relapse definitely affects your ability to care for a child.