Yes, as stated earlier, levels of hCG rise quickly at the beginning (and throughout the first trimester), and peak at 8-11 weeks, when they normally stop increasing and begin to fall.
On the other hand, hCG levels can fluctuate during the day, being higher in the morning simply because that is when the urine is most concentrated, and that is the reason why you are recommended to take a HPT in the morning. Some women have more concentrated urine in the afternoon or even in the evening. All in all, it varies from pregnancy to pregnancy.
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