Contraceptive action (attempts to prevent pregnancy)

1. Preventing Ovulation: The hormones in the pill try to stop the ovaries from releasing an egg each month (ovulation.) Research shows that the pill does not always stop ovulation every single month.

2. Thickens Mucous: The pill changes the cervical mucous and makes it thicker and more difficult for the sperm to move and then fertilize an egg (ovum.)

3. Changes Tube Movement: The pill changes the movement of the fallopian tubes and therefore makes it more difficult for the sperm to move and fertilize an egg.

Abortifacient action (attempts to kill the baby)

4. Interferes with Communication: When implanting and about to implant, the baby chemically "talks" to the lining of the womb in order to properly position himself or herself prior to implantation and for implantation to occur. The pill interferes with these lines of communication, preventing the baby from implantation.

5. Prevents Implantation: When conception occurs, the baby travels down the fallopian tube and implants in the lining of the uterus. However, the pill alters the lining of the uterus (endometrium.) The lining of the womb changes and doesn't grow to its proper thickness. Therefore, the baby cannot implant itself and dies. Or, if implantation occurs, the baby dies from lack of nutrition (he or she starves to death) because the lining of the uterus cannot properly sustain life.

6. Interferes with Integrins: The baby needs help to attach to the lining of the womb and that is where integrins come into play. Think of an integrin as a clamp that holds onto the baby while the baby implants. The pill interferes with integrins-they don't work correctly or are not even present-so again the baby dies from lack of nutrition.

You may better understand the abortifacient properties of the pill by considering the example of a space shuttle, low on fuel and oxygen, which urgently needs to dock with the mother ship. The mother ship and the shuttle communicate with each other so that the shuttle knows which docking bay to go to. Importantly, the mother ship knows which bay to make ready. If this electronic communication fails (in the womb--disrupted chemical "cell-talk") the shuttle may go to the wrong docking bay, fail to attach to the mother ship, drift away, and the crew dies from a lack of food and oxygen. Or it might go to the right bay but not find all the docking apparatus in place. Again, the attachment between the two fails due to faulty communication and the crew dies. Or the ship docks but the mother ship is empty and abandoned, without food, without anyone to help and the crew dies.

The above taken from The pill-how it works and fails By John Wilks B.Pharm MPS MACPP. These facts cover all the pills available in the U.S. today.