Is 642 a good level for pregnancy hormones at 3 and half weeks?

The reference range for serum hCG levels at 3.5 weeks of gestation is typically between 18 to 473 mIU/mL (milli-international units per milliliter). Since 642 mIU/mL falls within this range, it is considered normal. However, it's important to note that hormone levels can vary between individuals and can double every 48-72 hours in early pregnancy. If you have any concerns or questions, it's always best to consult with a healthcare professional for personalized advice.