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In the 1960s, the U.S. Food and Drug Administration approved a contraceptive that allowed women to plan desired pregnancies and prevent unwanted pregnancies. Oral hormonal contraception ('the pill') uses synthetic hormones similar in structure to progesterone and/or estradiol. What is the pill's mechanism of action?
Imagine that four different contraceptives are under development. One blocks ovulation, one blocks fertilization, one blocks cleavage, and one blocks implantation. In the United States, which contraceptive is likely to be the least controversial to bring to market? Why?

Verified step by step guidance

1. Understand the mechanism of action of oral hormonal contraceptives: The pill primarily works by preventing ovulation. It contains synthetic hormones similar to progesterone and/or estradiol, which maintain consistent hormone levels in the body, preventing the surge in luteinizing hormone (LH) that triggers ovulation.
2. Explore the different stages of reproduction that contraceptives can target: Ovulation, fertilization, cleavage, and implantation are key stages in the reproductive process. Each stage can be targeted by different contraceptive methods.
3. Consider the societal and ethical implications of each contraceptive method: In the United States, contraceptives that prevent ovulation are generally less controversial because they prevent the release of an egg, thus avoiding fertilization and subsequent stages of pregnancy.
4. Analyze why blocking ovulation is likely the least controversial: Blocking ovulation is seen as preventing the possibility of pregnancy from the outset, rather than interfering with a fertilized egg or embryo, which can raise ethical concerns.
5. Conclude with the likely choice for market approval: Given the societal acceptance and ethical considerations, a contraceptive that blocks ovulation is likely to be the least controversial and most acceptable option for market approval in the United States.

Key Concepts

Mechanism of Action of Oral Contraceptives

Oral contraceptives, commonly known as 'the pill,' primarily function by preventing ovulation. They contain synthetic hormones similar to progesterone and estradiol, which inhibit the release of gonadotropins (LH and FSH) from the pituitary gland. This suppression prevents the maturation and release of eggs from the ovaries, thereby reducing the likelihood of fertilization and pregnancy.

Stages of Human Reproduction

Human reproduction involves several key stages: ovulation, fertilization, cleavage, and implantation. Ovulation is the release of an egg from the ovary. Fertilization occurs when a sperm cell unites with an egg. Cleavage is the series of cell divisions that occur after fertilization, and implantation is the attachment of the embryo to the uterine wall. Each stage is crucial for a successful pregnancy.

Ethical and Social Considerations in Contraceptive Development

The development and approval of contraceptives often involve ethical and social considerations. In the U.S., contraceptives that prevent fertilization, such as those blocking ovulation, are generally less controversial because they prevent pregnancy before it begins. In contrast, methods that interfere with post-fertilization stages, like implantation, may raise ethical concerns about the beginning of life, making them more controversial.