honestly depends on how it happened

if you got pregnant from some random degenerate then it'd be a dealbreaker since i would have a hard time trusting you
if you were in a long term commited relationship already when it happened then i think i could be fine with it, as long as you seem like you are loyal and trustworthy and nice
if you were married & had a kid & got divorced, then it wouldnt really bother me that much at all

my mom had a kid(my brother, technically half brother obv) with some guy before she met my dad who she later married, while my brother was 2 years old, and i know she's a great person so i can't judge you or people like you for your situation.
my main issue that i want a christian girl(which already excludes like 80% of young girls...) and i think single mothers usually aren't since it usually happens from sex outside of marriage. but i get that people can change and regret things, so no, being a single mother isnt a dealbreaker at all by itself for me