You'll need to take pictures so that we can see what you are talking about. I'm thinking that you've seen one of what we call the 'true bugs' because of your description of the cross (more like an X) on the back.

Regardless, I can't think of a single insect that I could consider poisonous. Don't go nuts and spray with a bunch of pesticides that COULD be very hazardous to you and the unborn baby. Take some pictures so that we can help with an ID.

You might also disclose what kind of plants you saw this insects on.

Your insect was nicely identified in your other post, and I stand corrected! I've never lived in an area where blister beetles were common, and certainly not this one! What a beauty.

I suggest that you call your extension office and find out what your best action might be. It might be that ignoring them is the best suggestion for now.

What seems to be the plants they like?

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