[telecky1982]

My wife in Dec was two weeks late, then in Jan and Feb did not have a period at all - She has had three negative at home tests at different times?

[DoulaLC]

If she normally is very regular, it would be wise for her to see her doctor for a test there. They may order a blood test done. If she is not pregnant, they would then check to see if another cause can be determined.

[Fr_Chuck]

It is possible Being late does not of course mean pregnant, but missed does, It also can be a sign for many other things. As noted a doctors visit is called for.