Endometrial Lining

Since I've been TTC, my periods have been extremely short (3-4 days with only one heavy day) so I've been doing my research. One thing I came across is shorter periods can be a result of a thin endometrial lining possibly leading to fertility issues. Anyone read this before? Thoughts?

It would make sense if it's true bc one of the reasons they listed for a thinning endometrial lining is lack of blood flow. Since I've gotten my desk job, my periods have been lighter.