I'm assuming na ang pinagkaiba lang nila is yung process. OGTT kasi fasting for 8 to 10 hours tapos 3x ka nila kunan ng blood test (1st, kukunan ka nila ng dugo before you take the glocuse juice. After drinking the juice, 2nd blood test after an hour. 3rd kuha, for the 2nd hour.) OGCT is isang beses ka lang kukunan. Depende yan sa OB mo sis kung neccessary mo pa bang kuha ng OGTT.