I'm tempted to answer that no one have a weird fetish.
Not because there isn't such thing as weird fetishes, but because the weirdness can only be in the eyes of an external person.
A fetish is defined as being "an object or bodily part whose real or fantasied presence is psychologically necessary for sexual gratification and that is an object of fixation to the extent that it may interfere with complete sexual expression". I took the
You must be registered to see the links
definition, but globally all goes in the same way.
In a more generic way, a fetish is something that increase your arousal, and in the end your pleasure. This while something that you would find weird would, at the opposite, tend to decrease your arousal, and therefore also your pleasure. What mean that, if it's your fetish, then it's not something weird to your eyes, this whatever how it can be seen by others.
As for your question:
Is it weird that I like pregnant women?
Not only it's not weird, but also, as you phrase it, it's not a fetish, just a liking or, at most, a preference.