Credit Green Bay Packers . In essence, the system is a complex grid of retractable arms lined with hundreds of greenhouse-type light bulbs. After a trial run in 2010, the Packers bought nine MU360 units, as they are called, enough to cover half the field.
IUD Progesterone. An Intra-Uterine Device (IUD) is a small, flexible, plastic device placed inside a womanâs uterus. Mirena is the brand-name for a type of IUD that releases synthetic progesterone hormone into a womanâs body. The IUD makes it harder for sperm and eggs to move, or for a fertilized egg to lodge in the uterus. It is 99.8% effective in preventing pregnancy, making it slightly more effective than sterilization.
How does an IUD prevent pregnancy? Both types of IUDs work primarily by preventing sperm from fertilizing an egg. The copper IUD releases copper into the uterus, which works as a spermicide. The others release a form of the hormone progestin into the uterus. The progestin thickens the cervical mucus so that sperm can't reach the egg.