Progesterone pill and its mechanism of action

Progesterone, a hormone produced by the ovaries, plays a crucial role in the menstrual cycle and pregnancy. Progesterone pills, also known as progestin-only pills or mini-pills, are a form of hormonal contraception. They contain synthetic progesterone, which mimics the natural hormone's effects in the body. These pills work primarily by preventing ovulation, or the release of an egg from the ovary.

1. Ova formation
Progesterone pills prevent pregnancy by suppressing ovulation, which means they inhibit the formation of ova or eggs. By maintaining a consistent level of progesterone in the body, these pills prevent the release of eggs from the ovaries, ensuring that there is no ovum available for fertilization.

2. Fertilisation
Since progesterone pills prevent ovulation, they indirectly prevent fertilization as well. Without the presence of an egg in the fallopian tube, there is no opportunity for sperm to fertilize it. It is important to note that progesterone pills do not directly affect sperm or their ability to fertilize an egg.

3. Implantation
Progesterone pills primarily work by inhibiting ovulation, and their effect on preventing implantation is minimal. However, it is worth noting that if fertilization does occur despite the use of progesterone pills, these pills also make the uterine lining less receptive to implantation. This secondary mechanism helps further reduce the chance of pregnancy by preventing the fertilized egg from attaching to the uterine wall.

Conclusion
In conclusion, the correct answer is option 'A' - Progesterone pills help prevent pregnancy by not allowing ova formation. These pills primarily work by suppressing ovulation, ensuring that there is no egg available for fertilization. While they may also have a secondary effect on reducing the receptivity of the uterine lining for implantation, their primary mechanism of action is preventing the release of eggs from the ovaries.