characteristics of a perfect contraceptive
100% reliable and safe
Unrelated to Coitus
Completely reversible within 24 hours
No Discomfort
what is Combined Oral Contraception and how does it work?
- pill, COCP
- combination of oestrogen and progestogens
- supra-physiological levels, negative feedback on HPG axis, so no GnRH, FSH or LH, no follicle development and no ovulation
what are progestogens?
group of compounds that best represent progesterone in the steroid pathway
where do the oestrogens and progestogens act?
- anterior pituitary
- ovary
- endometrium
progestogen- only effects in COCP?
- endometrium thinning not proliferating or becoming secretory, so even if you were to ovulate, it won’t implant
- putting the fallopian tube to sleep – cilia that usually waft the egg become lazy, delays gamete transport
- thickening of cervical mucus so sperm cannot enter (glycoprotein mesh)
what would happen if you gave someone oestrogen but no progesterone?
endometrium would grow and grow and grow, then proliferate and there will be a very heavy bleed.
benefits of COCP?
- Reliable and Safe
- Unrelated to coitus
- Woman in control
- Rapidly reversible, fertility comes back within the next cycle
- halves your risk of ovarian cancer.
- thins the endometrium, so reduces risk of endometrial cancer
- people don’t have to have their heavy or painful periods
risk of COCP?
- increased risk of clotting (DVT) because of high oestrogen levels
- small risk of liver cancer
- risk of Crohns and weight gain
- mood swings, depression
- jaundices, gall stones
- migraines
- high blood pressure
who can’t take COCP?
over 35’s who have high BP because risk of cardiovascular disease goes up
Combined Oral Contraception Pill Rules
- Start 1st packet 1st day of period
- Take 21 pills and stop for 7 day break (PFI)
- Pill packet has days labelled
why is a 7 day break allowed with COCP?
-allowed because suppression on hypothalamus and pituitary will only lift after 10 days, as that’s when the next cycle will kick back in
Interacting medication with COCP?
- liver enzyme inducing drugs
- affect oestrogen and progestogen metabolism - broad spectrum antibiotics
- affect enterohepatic circulation of oestrogen only (40% of pill is recycled)
what is a combined vaginal contraceptive?
- same as COCP except vaginal delivery (ring) for 21 days, remove for 7 days
- Adv = don’t have to take every day
what are the methods for using Progestogen Only Methods?
Default Methods
- Implants: Nexplanon - 3 year implant, bit of anaesthetic, goes under the skin subcutaneously
Norplant (LNG)
2. Hormone releasing IUCD:
Mirena IUS (LNG)User Dependent Methods
POPs
- Desogestrel (Cerelle) - cerelle has a favourable side effect profile vs older POPS - Norethisterone - Ethynodiol diacetate - Levonorgestrel - Norgestrel
Injectables
- Depo Provera (MPA) (12weekly) - Noristerat (NET)
Mirena is an intra uterine device (progestogen only default method) that releases progestogen Into the uterus - explain the benefit of this:
progesterone released straight into the uterus
- the good thing it doesn’t have to be absorbed into the blood stream, so side effects are extremely reduced
- if you had it in your arm it would immediately absorb into your bloodstream, potential for more side effects
Cerelle is a progestogen only pill - why might this be better than using a COCP?
- as effective as COCP
- bleeding as predictable as COCP
- one less hormone to worry about, less contraindications
- if you forget to take a tablet you have a 12 hr window, but with COCP its only 3 hrs
IUCD’s
intrauterine contraceptive devices
Copper bearing intrauterine contraceptive devices are inserted into the uterus by trained practitioners. Sit inside the uterus, very small and wound with copper at the top.
Copper is spermicidal, and when you put a foreign body into the uterus it causes inflammation so you get a sterile endometritis which then means even if the sperm and egg get together the embryo won’t implant.
Left in situ long term, act by
- Destroying spermatozoa
- Preventing implantation – Inflammatory reaction and prostaglandin secretion as well as a mechanical effect
-also have hormone bearing IUCD’s, like mirena
how long can all IUCD’s be inserted for?
5 years
-any device inserted after the 40th birthday could be left in until after the menopause if the woman wishes without being replaced
types of IUCD’s
- copper bearing
Ortho T 380 – 8 -12yr
Multiload 375 – 5yr
Nova T 380 – 5yr - hormone bearing
Mirena (IUS) – 5yr
IUCDs-
Benefits
- Non user dependent
- Immediately effective
- Immediately reversible
- Can be used long term
- Extremely reliable
- Unrelated to coitus
- Free from serious medical dangers
IUCDs-
Disadvantages
- Has to be fitted by trained medical personnel
- Fitting may cause pain or discomfort
- Periods may become heavier and painful
- It does not offer protection against infection
- Threads may be felt by the male
IUCDs-
Risks
- Miscarriage if left in situ if a pregnancy
- ectopics - protects less well against ectopics
- May be expelled
- The uterus may be perforated, 1/1000 insertions
IUCDs-
Absolute contraindications
Current pelvic inflammatory disease
Suspected or known pregnancy
Unexplained vaginal bleeding
Abnormalities of the uterine cavity
IUCDs-
Relative contraindications?
- Past history of pelvic inflammatory disease
- Not in mutually monogamous relationship
- Menorrhagia / Dysmenorrhoea
- Small uterine fibroids
