Brief Answer:
maybe for ever

Detailed Answer:
Hi,

Thanks for writing to HealthcareMagic.

First of all, there has not been any study of meth on an unborn baby.

But in a normal adult, meth has a half life of 6-12 hrs, and it is excreated in the urine.

But the problem with the unborn baby is that, it literally floats in his urine, and drinks it and pees in it. The amniotic fluid around the unborn baby is to a great extent formed by his urine.

So if he is exposed to meth, via the blood of his mother through the placenta, then it will get excreated via the urine into the amniotic cavity, and when he takes a gulp of that fluid, it will again go inside his system and the cycle may continue. And after being born he may show signs of meth withdrawl.

So ask the mother to immediately stop meth smoking to prevent any further exposure.

Hope i have been helpful.

Regards,
Dr. Deepika Patil

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