Ti generalize the expression to both genders, in Italy the pair can refer to testicles, breasts or ovaries. The point being “having significant reproductive potential”... I hope it will never be poco’d to avoid offending people that have reproductive disorders.

My point was more that what most people want to express is “guts”. But they’ll go for “balls” because it needs to be about sex and hormones, what else could it be, right ?