In the past, women having difficulty conceiving might have been advised to limit their caffeine intake. But recent studies suggesting that stimulating drinks, and specifically green tea, might boost fertility. In a study conducted at Kaiser Permanente Medical Care Program of Northern California in Oakland, researchers found that women who drank more than one half cup of caffeinated green tea every day doubled their odds of conceiving. No significant association was found for other caffeinated beverages; therefore researchers concluded that a chemical component of tea other than caffeine might have been responsible for the increase in fertility.
https://www.babyhopes.com/articles/greentea.html
I guess it just depends on where you get the info.