Because of the risk of tuberculosis to the fetus, treatment of tuberculosis in pregnant women should be initiated whenever the probability of maternal disease is moderate to high. The initial treatment regimen should consist of isoniazid, rifampicin, and ethambutol. Pyrazinamide can probably be used safely during pregnancy and is recommended by the WHO and the International Union against Tuberculosis and Lung Disease (IUATLD). Although all of these drugs cross the placenta, they do not appear to have teratogenic effects. Streptomycin has harmful effects on the human fetus (congenital deafness) and should not be used and prothionamide is teratogenic.
NB If pyrazinamide is not included in the initial treatment regimen, the minimum duration of therapy is 9 months.
As in the general population pyridoxine supplementation (10-25 mg/day) is recommended for all HIV positive patients taking isoniazid, including pregnant women.