Thanks for visiting HCM.
First of all I would have enquired, how you came to know that you have ''latent'' tuberculosis. Because if it is the case then just taking isoniazide or combination of isoniazide and rifampicin
for 6 months would have been adequate.
Your doctor has prescribed you treatment as if you have got active tuberculosis
Let me assure you that no anti-tubercular drug is contra-indicated in pregnancy
and you can continue with your regimen to complete six months of treatment.
This is the WHO recommendation for treatment of tuberculosis in a pregnant patient and can be checked on its site.
Only thing is, you need to take tablet pyridoxine
along with current medication to prevent isoniazide induced peripheral neuropathy
Best wishes and congratulations