Hey there, I got so frustrated using MB because it was so inconsitent for me. I was doing tests every morning upon waking as per the instructions and got transition and pebbles most of the month then ferning right before AF. Then the next month i would get ferning for a couple of days but didnt seem to fall in the right time according to my temp charting. Then the next month it would be different again The pamphlet that it comes with says that it doesnt work for women with high level of oestrogen so there must be heaps of them out there cos I have heard lots of people have had problems with MB.
I ended up selling mine online and buying OPK's instead. The ones that Lullaby Conceptions sells are really excellent and they are very sensitive for me and tell me exactly the days when I ovulate.
Worth giving them a go as they are cheap if you order the value packs.... much cheaper than the chemists and supermarkets!