I am online and will be happy to answer your questions.
thank you for your patience.
the exact prognosis is not possible to tell without examining the baby. however to answer your questions.
risk is lower if only used in last trimester and much more if used throughout the pregnancy esp in first trimester.
Babies who are born to opiate-abusing mothers have lower birth weights, and these infants are at greater risk of sudden infant death syndrome (SIDS).
also risk of neonatal respiratory depression, lung immaturity are observed in infants of mothers who abused opiates.
use in first trimester can cause heart defects.
I recommend talking to pediatrician taking care of baby. may be baby has only respiratory depression/ respiratory issues or increased bilirubin ( most common causes of neonate to be in ICU ). it is not possible to say what condition baby has.
Please let me know if i should provide clarifications. thank you