I have data for the lipid profile before treatment, 4 weeks, 12 weeks after treatment.

Paired data analyses showed that LDL significantly increased 4 weeks after treatment, and no difference was noted between 4wk and 12 wk.

Could I conclude that the increase will mostly occur in 4 weeks after the treatment starts, and it isn't significant thereafter?

What is a better analysis for the conclusion I want?

Thank you.