Bitterbarren tea

Though not precisely the latest medical innovation, one of the most important new treatments in the era of the Cathrican Empire is bitterbarren tea.

The bitterbarren plant is a creeper related to mint, making it stubborn, invasive, impossible to kill, and hardy enough to grow just about anywhere. It tastes awful and tends to cause vomiting and a racing heart. Its leaves are even covered in obnoxious, poky hairs on the underside. It got its name by taking over any field it snuck into and rendering it useless for many of the food crops favored by the Empire -- only cowpeas and a few species of lentils could restore a field stripped by bitterbarren. It has spent most of existence widely reviled; the only surviving mentions of bitterbarren from before the Cathrican Empire are creative insults for obnoxious people and strategies for getting rid of it. (Burning is a popular strategy.) It was thoroughly reviled until the discoveries of the Cathrican Empire.

Though the exact origin is unknown, some years ago it was discovered that an alcohol tincture of dried bitterbarren leaves will react when steeped with the Camellia sinensis leaf to form a reasonably tolerable beverage that reliably prevents conception in mammals that might carry a child. That is to say, a simple and reliable tincture brewed from an invasive weed that takes less than a week to soak can be mixed into tea, and as long as it is stirred or even ignored for five or ten minutes it will prevent pregnancy for the duration of one menstrual cycle. A year's worth of contraception costs less than a bottle of whiskey almost everywhere in the Empire, and many public institutions and charitable endeavors provide bitterbarren tea for free to anyone who asks. It is but one of Empress Cathrica's many efforts to ensure that all the citizens of her empire have equal rights and opportunities.