Reusable menstrual cups reduce waste and are more cost-effective than single-use pads and tampons. But some people avoid the cups because they require thorough cleaning and are sometimes messy to empty. To solve these problems, researchers coated a commercially available silicone cup in silicone oil and created a plant-based, absorbent tablet. These design adjustments could make menstrual cups safer and easier to use, according to a study published in ACS Applied Materials & Interfaces.