Ovarian and Menstrual Cycles

Flashcards covering the key concepts of the ovarian and menstrual cycles, including hormonal regulation and phases.

What is the key difference between the ovarian and menstrual cycles?

The ovarian cycle involves hormone production within the ovaries, while the menstrual cycle (in the uterus) primarily responds to these hormonal signals without producing hormones itself.

What is the role of GnRH in the ovarian cycle?

GnRH (gonadotropin-releasing hormone) initiates the ovarian cycle by stimulating the production of FSH and LH in the anterior pituitary.

Which hormone stimulates follicle development in the ovaries?

FSH (follicle-stimulating hormone) stimulates the growth and development of follicles in the ovaries.

What hormones are produced by the ovaries?

Estrogen and Progesterone

What is the importance of the dominant follicle?

The goal is to have just one follicle completely mature, The dominant follicle is the one that gets to ovulate.

Follicular Phase

It goes from day one through day fourteen of a regular twenty eight day cycle. It is when the follicle is growing and it is the time when the follicles wrapping produces estrogen.

What happens during ovulation?

The mature follicle releases an egg. The egg travels into the fallopian tube, where fertilization can occur.

Where does fertilization typically occur?

Fallopian tube

What is an ectopic pregnancy?

A pregnancy that occurs outside of the uterus, most commonly in the fallopian tube.

What are the symptoms of an ectopic pregnancy?

Severe one-sided lower abdominal pain in a female of reproductive age.

Luteal Phase

It occurs after ovulation, and the corpus luteum develops, and that's the structure that produces progesterone

What is the corpus luteum?

The structure that develops after ovulation from the remaining follicular cells. It primarily produces progesterone.

What is the corpus albicans?

Corpus albicans makes no hormones. And it's just the leftover scar tissue from that ovulation event.

Menarche

Menarche is the word for the first menstrual cycle that someone has.

Menopause

The very, very last menstrual cycle that someone has.

What are the three phases of the uterine cycle?

Menstruation phase, Proliferative phase, Secretory phase

What happens during the menstruation phase of the uterine cycle?

The endometrial lining is shed.

What is the myometrium?

A muscular layer that gives you cramps every month, unfortunately.

What is the role of estrogen in the ovarian cycle?

While Follicle Stimulating Hormone is developing, the wrapping produces estrogen.

During the follicular phase, which hormone dominates?

FSH (follicle-stimulating hormone).

Ovulation

LH is what drives ovulation. It signals the ovary when its time to release the egg

What is the effect of low concentrations of estrogen on GnRH, FSH, and LH?

At low concentrations, estrogen does negative feedback on GnRH, FSH, LH.

What is the effect of high concentrations of estrogen on GnRH, FSH, and LH?

High concentrations of estrogen are gonna switch and do positive feedback.

Once ovulation completes, what happens to estrogen levels?

The estrogen levels are going to decrease because the structure is no longer producing estrogen.

What is the role of progesterone after ovulation?

The brain knows that pregnancy happened because progesterone gives time to get that fertilized egg from the fallopian tube to the uterus.

What is the feedback effect of progesterone on GnRH, FSH, and LH?

Progesterone sends out negative feedback during normal cycle or birth when on birth control to inhibit the release of GnRH, FSH, and LH, preventing ovulation and maintaining the uterine lining.

How is birth control effective?

Progesterone is in birth control because it effectively suppresses the natural cycle that leads to ovulation. It suppresses the HPG axis.

What causes menstruation to begin?

When progesterone levels drop, that triggers the endometrial lining to start menstruating.

What is the fertile window during a 28-day cycle?

Anywhere from day nine to 16 of the cycle is where you could get pregnant during a twenty eight day cycle.

How long can sperm survive in the female reproductive tract?

Up to five days.

How long is an egg cell viable after ovulation?

About twenty four hours after ovulation.

How does Plan B work?

It is essentially the same as blocking progesterone.

Dysmenorrhea

Dysmenorrhea is like excessive cramping or other discomfort that happens with the menstrual cycle.

Menorrhagia

Menorrhagia is like heavy menstrual bleeding.