Why do they call it dirty 30?

Why do they call it dirty 30? The Urban Dictionary defines the “dirty 30s” as the age at which single women without children realize that their biological clock is ticking and, as a consequence, may lower their standards … in order to find a mate.” Hah.

The Urban Dictionary defines the “dirty 30s” as the age at which single women without children realize that their biological clock is ticking and, as a consequence, may lower their standards … in order to find a mate.” Hah.
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