Honestly, most of us just go with whatever ang doctor prescribed kasi covered ng prenatal vitamins naman usually! But if kailangan mo ng separate ferrous sulfate, ang generic ones from Mercury Drug or Watsons are super affordable, like PHP 50-150 depending sa dosage, and they work just fine. A few of my mum friends just stuck with their prenatal vitamins kaya di na kailangan ng extra iron supplement, but best na tanungin mo talaga ang OB mo kung kailangan mo pa ng additional ferrous sulfate or if your prenatal is enough na, kasi depende sa hemoglobin levels mo.