Fisiologi Siklus Menstruasi (5/5) - Siklus Menstruasi Normal

Summary

The video explains the menstrual cycle, detailing the hormonal processes that regulate ovulation and menstruation. It covers the role of estrogen in thickening the endometrium and inhibiting FSH production to ensure only one dominant follicle survives. Progesterone’s role is discussed in preparing the endometrium for possible pregnancy after ovulation. The cycle of hormonal peaks, including estrogen and progesterone, and their impact on the endometrium and ovulation is explained. Additionally, the transition to the luteal phase and the production of hormones by the corpus luteum are highlighted. The entire process is set within the typical menstrual cycle length of 21 to 35 days.

Takeaways

• 😀 Estrogen plays a key role in thickening the endometrium in the early stages of the menstrual cycle.
• 😀 Estrogen also provides feedback to the hypothalamus to reduce FSH production, allowing only one dominant follicle to survive and mature.
• 😀 The dominant follicle (Graafian follicle) produces sufficient estrogen, which triggers a rise in LH, leading to ovulation.
• 😀 After ovulation, the egg enters the fallopian tube, where it can be fertilized within 24 hours. If not fertilized, it dies.
• 😀 The corpus luteum, formed after ovulation, continues to produce estrogen and progesterone, delaying menstruation until the egg is no longer viable.
• 😀 Progesterone peaks after ovulation, helping prepare and maintain the endometrium for possible implantation of a fertilized egg.
• 😀 Estrogen peaks just before ovulation, preparing the endometrium for implantation and affecting cervical mucus and FSH levels.
• 😀 Rising estrogen levels decrease FSH levels, preventing the development of other follicles and ensuring only one follicle matures.
• 😀 LH surges in response to rising estrogen levels, triggering ovulation and the release of the egg from the mature follicle.
• 😀 After ovulation, the corpus luteum produces progesterone and estrogen, continuing to prepare the endometrium for a potential pregnancy.
• 😀 A typical menstrual cycle lasts between 21 to 35 days, with menstruation occurring after the egg is no longer viable and the hormone levels drop.

Q & A

What role does estrogen play in the menstrual cycle?

Estrogen helps in thickening the endometrium during the initial phase of the cycle. It also has feedback effects on the pituitary gland, reducing FSH levels, and promoting the development of the dominant follicle, which will eventually lead to ovulation.

How does the body regulate follicular development?

During the menstrual cycle, estrogen helps to suppress the production of FSH once the dominant follicle produces enough estrogen. This negative feedback prevents the development of other follicles, allowing only the dominant follicle to mature and eventually ovulate.

What happens after ovulation in terms of hormone production?

After ovulation, the ruptured follicle transforms into the corpus luteum, which produces both estrogen and progesterone. Progesterone helps to further prepare the endometrium for a potential pregnancy by thickening, vascularizing, and increasing glandular activity.

What is the role of progesterone in the menstrual cycle?

Progesterone peaks after ovulation and plays a critical role in maintaining the thickened endometrium. It prepares the endometrium for potential implantation by enhancing its nutrient supply and making it more receptive to a fertilized egg.

How does estrogen influence FSH production?

Estrogen causes a decrease in FSH production through negative feedback. As estrogen levels rise during the follicular phase, it suppresses FSH, which prevents the maturation of multiple follicles and ensures only one dominant follicle reaches ovulation.

What happens if fertilization does not occur after ovulation?

If fertilization does not occur, the egg dies within 24 hours. The corpus luteum, still producing progesterone and estrogen, eventually degenerates, and the levels of these hormones drop, leading to menstruation and the shedding of the endometrial lining.

What is the role of LH during ovulation?

LH (Luteinizing Hormone) surges just before ovulation, triggering the release of the mature egg from the dominant follicle. Estrogen's rise causes a feedback loop that leads to the LH surge, which is critical for ovulation to occur.

What happens to progesterone levels if pregnancy does not occur?

If pregnancy does not occur, progesterone levels begin to decline as the corpus luteum regresses. This drop in progesterone leads to the shedding of the endometrial lining, resulting in menstruation.

Why is the endometrium important for pregnancy?

The endometrium thickens and becomes more vascularized and glandular in response to estrogen and progesterone. This makes it the ideal environment for embryo implantation and the support of early pregnancy if fertilization occurs.

What is the typical length of a menstrual cycle?

The typical menstrual cycle lasts between 21 and 35 days, with fluctuations depending on the individual. The cycle includes various hormonal changes that prepare the body for possible fertilization and pregnancy.