Well, abstention is 100% effective, but I don't agree that the natural method is 100% effective. That's not bourne out by research, but that's not important.

The Pill is composed of estrogen and progesterone in varying amounts based upon the time period the Pill is taken. That's how it works.

When taking an unnatural amount of those hormones, then women are getting a MASSIVE dose. A hormone is like a drop of water in an olymic swimming pool of water. That's the natural way the body produces hormones by comparison. The massive dose can make women quite ill.

I'm sure some readers have stopped taking the Pill for such reasons and then had a massive menstruation as a result the first time after cessation. It honestly is bad for the body as should be self-evident.