Week 7.1 - Contraception and infertility Flashcards
How does barrier contraception work?
-Prevents sperm reaching cervix
How does a diaphragm work?
-Inserted across the cervix to hold the sperm in the acidic environment to reduce survival
Name 4 hormonal contraceptions which prevent ovulation
- Combined OCP
- Depot progesterone
- POP (may inhibit ovulation)
- Progesterone implant (may inhibit ovulation)
How does the combined OCP inhibit ovulation?
- Negative feedback of oestrogen and progesterone inhibits follicular development
- loss of +ve feedback of oestrogen -> no LH surge
How often are depot injections?
-Every 3 months
How does depot progesterone inhibit ovuation?
-Negative feedback of progesterone inhibits ovulation by preventing follicular development and LH surge
Which contraceptions have producing a thick cervical mucus as there main method of action?
- POP
- Progesterone implant
How does producing thick cervical mucus act as a contraception?
-Prevents passage of sperm into cervix
Which hormonal contraceptions act by altering receptivity of endometrium for implantation?
- Emergency contraceptive pill
- Intrauterine devices
How long after coitus does the emergency contraception work?
-upto 72 hours
How do intrauterine devices work?
-Make endometrium hostile by interfering with endometrial enzymes
Name 3 methods of surgical contraception
- Ligation
- Clips
- Rings
What is the emergency contraceptive pill?
-High dose of combined OCP
Define infertility
-Failure to conceive within 1 year of trying
How common is infertility?
-Affects ~ 15% of couples
What % of infertility is due to male/female problems?
- 20-25% male
- 45-60% female
- 20-30% unexplained
Give 5 causes of infertility
- Coital problems
- Anovulation
- PCOS
- Tubal occlusion
- Abnormal/Absent sperm
When is anovulation normal?
-Occasional, especially at extremes of age
List some causes of anovulation
- Ovarian failure
- Chemo/radiotherapy
- Pituitary tumour
- Weight loss
- Stress
- Exercise
- Hyperprolactinaemia
What is PCOS?
-Elevated androgen secretion from theca cells of unknown pathogenesis producing the PCOS phenotype of excessive hair, amenorrhea/menorrhagia, anovulation, cystic ovaries and insulin resistance
Give 3 causes of tubal occlusion
- Scarring from infection
- Endometriosis
- Sterilisation
How is tubal occlusion diagnosed?
-Hysterosalpingogram
Give 3 causes of absent/abnormal sperm
- Testicular disease
- Infection
- Obstruction of ductus deferens
- Hypothal/pituitary dysfunction
How is anovulation diagnosed?
- Serum progesterone in middle of luteal phase (~day 21)
- Differentiate between causes by looking at hormone levels
Give the hormone profile of a women in menopause
- High LH/FSH
- Low oestrogen
Give the hormone profile of a women in ovarian failure
- High LH/FSH
- Low oestrogen
Give the hormone profile of a women with hypothalamic failure
-Low FSH/LS/oestrogen
Give 2 methods of inducing ovulation and state how they work
- Anti-oestrogen -> reduced -ve feedback to hypothal/pit -> increased GnRH/LH/FSH eg aromatase inhibitor
- Gonadotropins -> stimulates FSH/LH
Name 3 methods of barrier contraception
- Condoms
- Diaphragm
- Cap