Thank you for your reply Shannon.
Reading your posts and Facebook profile has provided me some reassurance that no matter how bad Teigan's birthmark becomes there is something that can be done about it. I would just prefer not to let it get too bad in the first place if I can help it. I was bullied at school so I know first hand how cruel people can be. I will do everything I can to prevent Teigan going through the same thing.
It would appear that most doctors here in the UK are under educated in relation to the newer treatments available now and are therefore relying on older guidelines. Whilst I don't want to rush into any unneccessary treatment I do not want to wait until the birthmark becomes ulcerated or Teigan struggles to feed.
I will certainly take your advice to take weekly photos. We are due to see the doctor again next week for my partner's 6 week check up so we will ask for a second opinion then and maybe suggest a referral to a specialist (there is one about 50 miles from where we live).
With any luck I am worrying needlessly and everything will sort itself out!