Owen was 6.5 months when we started, his beginning measurement was 20mm difference between either side of his head, and in 7 weeks we are down to 12mm, so they definatley work!
A 'normal' head is anything upto 6mm, although with a helmet if you chose to you can try and acheive 0mm, so perfectly symetrical, depends how long you want them to wear the band and how perfect you want to achieve.
Just so you are aware, flathead isnt just about cosmetic appearance, many babies have and will continue into adulthood with uneven eyes and ears, and dentition/jaw misallignment which can cause all manor of problems like migraines etc. Dont want to scare u, but wish I had known all of this earlier.
HV and GPs dont like to admit flathead is a problem as they are worried parents will revert to tummy sleeping, and we all know this isnt recommended!
Good luck whatever you chose, and more questions please ask, or take a look at the LOCband website
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