White discharge in pregnancy is very common and often just the hormonal changes of pregnancy, though it can sometimes mean a vaginal infection instead. Since your gynaecologist examined you herself before prescribing this capsule, it's meant to treat whatever she found, most often a yeast or bacterial infection, which is more frequent during pregnancy.
Next Steps
Continue it exactly as she prescribed, a medicine your own doctor started after examining you in person is considered appropriate for your pregnancy. Wearing breathable cotton underwear and keeping the area dry alongside the course helps too.
Health Tips
Go back to your gynaecologist sooner if the discharge turns yellow or green, smells strong, or you notice itching, burning or any bleeding.