O&G Flashcards
Where is oestrogen produced?
Premenopausal
Pregnancy
Post menopausal
- Ovaries (granulosa cells) - Placenta (during pregnancy) - Adipose tissue (postmenopausal)
What are the functions of oestrogen?
- Development of secondary sexual characteristics - Regulation of the menstrual cycle - Thickens the endometrial lining - Increases bone density - Enhances clotting factors
Where is progesterone produced?
- Corpus luteum (after ovulation)
- Placenta (during pregnancy)
- Adrenal glands (small amounts)
What are the functions of progesterone?
- Maintains the endometrial lining for implantation - Inhibits uterine contractions during pregnancy - Thickens cervical mucus - Inhibits GnRH, LH, and FSH release
Where is luteinising hormone (LH) produced?
- Anterior pituitary gland
What are the functions of LH?
- Triggers ovulation - Stimulates corpus luteum formation - Stimulates theca cells to produce androgens
Where is follicle-stimulating hormone (FSH) produced?
- Anterior pituitary gland
What are the functions of FSH?
- Stimulates follicle development in the ovaries - Stimulates granulosa cells to convert androgens to oestrogen
Where is gonadotropin-releasing hormone (GnRH) produced?
- Hypothalamus
What are the functions of GnRH?
- Stimulates the anterior pituitary to release LH and FSH - Regulated by negative feedback from oestrogen and progesterone
Where is prolactin produced?
- Anterior pituitary gland
What are the functions of prolactin?
- Stimulates milk production - Inhibits GnRH release (suppressing ovulation during breastfeeding)
Where is human chorionic gonadotropin (hCG) produced?
- Syncytiotrophoblasts of the placenta
What are the functions of hCG?
- Maintains the corpus luteum in early pregnancy - Stimulates progesterone production
Where is oxytocin produced and stored?
- Produced in the hypothalamus - Stored in the posterior pituitary gland
What are the functions of oxytocin?
- Stimulates uterine contractions during labour - Stimulates milk ejection (let-down reflex) - Promotes bonding and social attachment
What hormonal changes occur in menopause?
- Oestrogen and progesterone levels fall
- FSH and LH levels rise due to loss of negative feedback
How do hormonal contraceptives work?
- Combined oral contraceptive pill: Oestrogen and progesterone inhibit FSH and LH, preventing ovulation
- Progesterone-only pill: Thickens cervical mucus and thins endometrial lining
What is puberty?
- The process of physical and hormonal changes leading to sexual maturity and reproductive capability.
What is the average age of puberty onset in females?
- Between 8 and 13 years.
What is the average age of puberty onset in males?
- Between 9 and 14 years.
What is the first sign of puberty in females?
- Breast development (thelarche).
What is the first sign of puberty in males?
- Testicular enlargement.
What are the key hormones involved in puberty?
- Gonadotropin-releasing hormone (GnRH)
- Luteinising hormone (LH)
- Follicle-stimulating hormone (FSH)
- Oestrogen (females) - Testosterone (males)