My apologies - I've been told you only just started testing and don't have much data yet, so I'm putting a strikethrough on what I've written.
The folks currently using Lantus have been giving you good advice - they've been there, done that ... and seen what happens to folks who don't have enought data to give the insulin safely.
I do mean safely. There have been new members of this board who didn't find out how to shoot safely and have lost their beloved companions. Please don't become one of them.
A note on meter accuracy: the FDA allows them to read within 20% of the true value.
This means that:
test = low to high range
200 = 160 - 240
190 = 152 - 228
180 = 144 - 216
Have you got a spreadsheet of data yet? If yes, please share! We need to see the data.
Have you been testing daily before every shot and during the mid-cycle nadirs?
If you've been shooting for several weeks, are religiously testing before shots AND have gotten mid-cycle shots consistently to know how low she is going, we need to see the data to give you advice.
Both Lantus forums have information on how it works and how to use it, including dose adjustment. You should not adjust the dose unless you have regular mid-cycle tests available to know how low she goes. If she goes down under 50, she may earn a dose decrease ... but only if you have the data to support it.