The chip that all current citizens are now carrying is a prototype. This was sped into production due to the Ashpoint Incident. All citizens get chipped.
The chip has GPS tracking capabilities, and can register if something is seriously wrong with you. However, unlike the bracelets that were common issue, they cannot say what is wrong and they will not detect pregnancy. This chip has all your state information on it, name, date of birth, ID number, and even a digital picture. For men, it will code you in and out of work, and codes to the locks on your house, making it more difficult for someone to break in. It also codes when you pick up/drop off your kid at school. If you don't have a chip, the authorities will be called and you will be detained by some excuse until they arrive.
Chips are injected via a needle into your hand, between your thumb and index finger. It rests beneath the skin far enough that it would cause significant damage if you attempt to remove the chip without surgical knowledge. Most people find that once they get used to waving their hand at the sensors, living life with the chip is far easier and less intrusive than the bracelet was. (Especially for women)
Children aren't chipped until sometime between their 11 and 13th birthdays. Parents can choose how soon they wish their child chipped, but if it's not done by the 13th birthday, the authorities will be notified and the child chipped against the parents wishes.
With the bracelets, if a woman's vital signs dipped into dangerous ranges, emergency services would automatically be dispatched. The chip requires a 911 call to be placed---although, if your nervous system response becomes too slow, the chip will initiate a call - but by the time they reach you, it's likely to be too late. Don't count on the chip saving your life.
As a final note - This is a rushed and new technology. There are bound to be problems and complications. Read up on this technology. The only caveat on this is that these chips have 100 years worth of technology on 2019. Just keep that in mind when you play out issues.