Leech of this size is often referred to in the literature as leech-breeding mother.
This leech is usually older than 24 months, has had many feedings, has laid cocoons at least once in controlled breeding and usually weighs more than 5 grams.
The indicated weight of leeches is always indicative and a medium leech can weigh less or more.
A leech-breeding mother is used in controlled breeding to breed leeches. This leech has never been used on humans and feeds exclusively on animal blood.