Question about womanly matters

How do you pronounce the word menstruation? Sometimes I hear it pronounced men-stray-tion.

Other times I hear it pronounced men-strew-ay-tion.

And neither pronunciation seems more prevalent than the other. It’s neck-and-neck. One big, annoying tie.

And it’s not like asking if it’s pronounced Feb-rue-airy or Feb-you-airy, because menstruation is not just the name of a month.

It’s menstruation.

I realize that it shouldn’t be hard to ask about the pronunciation of a word, because it’s just a word, and I am an adult.

But it’s menstruation.  So it is.