Ay, based sa ultrasound mo, most likely nabuo na si baby mo around late September or early October, kaya ang expected delivery ay mid to late December! Ang conception ay usually around 2 weeks before ang actual fertilization, so if December 28 ang due date mo, that means around late September ang estimated date of conception. Pero honestly, ang ultrasound ang most accurate way to know, lalo na kung early pa lang ang ginawa mo, kaya trust mo na ang date na sinabi ng OB mo dahil yan ang based sa actual measurements ng baby! Excited na ba for December?