Female Reproductive Physiology

 

The female reproductive system physiology refers to how the organs and hormones involved in the female reproductive system function to support menstruation, fertilization, pregnancy, and childbirth.

1. Major Organs and Their Functions

Organ	Function
Ovaries	Produce eggs (ova) and release sex hormones (estrogen and progesterone).
Fallopian Tubes	Transport egg from ovary to uterus; site of fertilization.
Uterus	Nurtures the fertilized egg and supports fetal development.
Cervix	Connects the uterus to the vagina; opens during childbirth.
Vagina	Birth canal; receives sperm during intercourse.

 

2. Key Hormones

Hormone	Role
Estrogen	Promotes growth of uterine lining and secondary sex characteristics.
Progesterone	Maintains uterine lining for pregnancy.
FSH (Follicle-Stimulating Hormone)	Stimulates follicle growth in ovaries.
LH (Luteinizing Hormone)	Triggers ovulation and formation of corpus luteum.

 

3. Menstrual Cycle (Average 28 Days)

The menstrual cycle has four main phases:

a. Menstrual Phase (Days 1–5)

• Shedding of the uterine lining (endometrium).
• Triggered by a drop in estrogen and progesterone.

b. Follicular Phase (Days 1–13)

• FSH stimulates the growth of ovarian follicles.
• Dominant follicle matures and secretes estrogen.

c. Ovulation (Day 14)

• LH surge causes the release of a mature egg.
• The egg travels through the fallopian tube.

d. Luteal Phase (Days 15–28)

• Corpus luteum (from ruptured follicle) secretes progesterone.
• If no fertilization, corpus luteum degenerates → hormone levels drop → menstruation begins again.

 

4. Fertilization and Pregnancy

• Fertilization occurs in the fallopian tube.
• The fertilized egg (zygote) travels to the uterus and implants into the endometrium.
• Placenta forms and produces hCG (human chorionic gonadotropin), maintaining the corpus luteum and progesterone levels.

 

5. Puberty and Menopause

• Puberty: Starts around 9–13 years old; marked by the onset of menstruation (menarche).
• Menopause: Usually occurs between 45–55 years; menstrual cycles stop due to decreased estrogen and progesterone.