Why does the word dilemma have two pronunciations?

The word dilemma has caused a dilemma.

According to Oxford Dictionary (http://www.oxforddictionaries.com/definition/english/dilemma) Pronunciation is : /dɪˈlɛmə, dʌɪ-/

Which is di-lema or dye-lema.

The website "howjsay" (http://www.howjsay.com/index.php?word=dilemma) also gives two pronunciations.

I just don't understand why it has two pronunciations. Also, is one UK and the other US? I am unclear as to which pronunciation I should stick to. Does it vary according to its position in the sentence? Or should I randomly shoot the one the pops up in mind?

Any assistance would be highly appreciated.

Solution 1:

Generally the difference in pronunciation is regional or personal. Both pronunciations are acceptable. Choose the one that feels the most natural for you.

Solution 2:

Merriam-Webster says (translating to IPA) /dəˈlɛmə, also daɪˈlɛmə/. The fact that they put in also indicates that they think /dəˈlɛmə/ is the more common pronunciation.

Why does Merriam-Webster put a /ə/ rather than an /ɪ/ in the first vowel? That varies between American dialects, and it's an arbitrary choice they made.

Cambridge dictionaries online gives /dɪˈlem·ə/, /dɑɪ-/ for American English and /daɪˈlem.ə/, /dɪ-/ for British English. The fact that they've switched the order means they think /dɪˈlem·ə/ is more common for American English and /daɪˈlem.ə/ more common for British English. In fact, if you listen to their pronunciations, they use the first for American English and the second for British English.

So one is more common in the U.S. and the other is more common in the U.K. However, both pronunciations are used in both countries, and you should use whichever one you like best.