Mechanism of action of oral contraceptive pills is :-

Options

A. Prevents ovulation
B. Increases cervical mucous thickening
C. Acts as a spermicidal agent
D. Increases basal body temperature

Answer

**Step-by-Step Solution:**

1. **Understanding Oral Contraceptive Pills (OCPs):**
Oral contraceptive pills are medications taken by mouth to prevent pregnancy. Their primary function is to inhibit ovulation and create an environment that is less conducive to fertilization.

2. **Preventing Ovulation:**
The first mechanism of action of OCPs is the prevention of ovulation. They work by inhibiting the release of hormones necessary for the ovary to release an egg. If there is no egg released (ovulation), fertilization cannot occur, thus preventing pregnancy.

3. **Increasing Cervical Mucus Thickness:**
OCPs also increase the thickness of cervical mucus. This thickened mucus creates a barrier that makes it difficult for sperm to swim through the cervix and reach the egg. This further reduces the chances of fertilization.

4. **Basal Body Temperature Increase:**
Another effect of OCPs is a slight increase in basal body temperature. This increase can make the uterine environment less favorable for sperm and implantation, although this is a minor mechanism compared to the others.

5. **Spermicidal Action:**
It is important to note that OCPs do not act as spermicidal agents. Spermicides are substances that kill sperm, but OCPs do not have this function. Instead, they work primarily through hormonal regulation and changes in cervical mucus.

6. **Conclusion:**
In summary, the mechanisms of action of oral contraceptive pills include preventing ovulation, increasing cervical mucus thickness, and slightly increasing basal body temperature. However, they do not act as spermicidal agents.

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