Contaception 2 Flashcards
How does the copper coil work?
- It releases copper into the uterus which is toxic to sperm and ova - inhibits fertilisation
- Copper alters cervical mucus
- Prevents implantation
What is the licensed duration of the copper coil?
5-10 years
What are the advantages of the copper coil?
- If fitted after 40 can be left in place in situ until post-menopausal
- Suitable for patients on enzyme inducers - no interactions
- No evidence of a delay in the return to fertility once removed
- Licensed as an emergency contraceptive
What are the disadvantages of the copper coil?
- Must be fitted by a specialist
- Periods may become heavier, longer or more painful
What patient groups is the copper coil not suitable for?
- Untreated vaginal or pelvic infection
- Dysmenorrhea or menorrhagia
- Allergy to copper
How does the Progestogen only IUS work?
- Progestogen effects on the endometrium which prevents implantation
- Alters cervical mucus
- Releases levonorgestrel after insertion
What are the advantages of the IUS?
- Reduced menorrhagia
- Reduced dysmenorrhea
- Amenorrhea
- Reversible
Which patient groups is the Progestogen IUS not suitable for?
- Untreated genital/vaginal infection
- Current breast cancer/breast cancer in the past 5 years
- Current liver disease
- Less than 4 weeks post-partum
What are the risks associated with IUD/IUS?
- Pain in insertion
- Expulsion of the device
- Perforation if the uterine wall at the time of insertion or after
- LNG-IUS - breast pain, weight gain, acne, headache and ovarian cysts
- Weight gain
- Ectopic pregnancy
- Pelvic inflammatory disease
- Unscheduled bleeding
How does the Progestogen only injection work?
- Inhibit ovulation
- Thicken cervical mucus
- Create an unfavourable endometrium
What are the benefits of the injection?
- Can be used in patients with a BMI >35kg/m2
- Reduce PMS
What are the disadvantages of the injection?
- Not readily available
- ADR’s - unscheduled bleeding, weight gain, loss of bone mineral density (recovered with discontinuation)
Who can’t use the injection?
- Current or past breast cancer
- Current liver disease
- Current osteoporosis
- History of IHD/CVA/thromboembolic disease
How does the nexplanon (etonogestrel 68mg) work?
- Inhibits ovulation
- Alters cervical mucus
What are the advantages of the implant?
- Help relieve dysmenorrhea
- Associated with reduced pain in endometriosis
Who isn’t suited for the implant?
- Active breast cancer/last 5 years
- Liver disease
- Active venous thromboembolic disorder
What are the ADR’s with the implant?
- Unscheduled bleeding
- Complications with removal
What is the copper IUD for emergency contraception?
Inhibits fertilisation - emergency contraceptive taken within 120 hours of upsi
Painful to insert
Most effective
How does levonorgestrel 1.5mg work as an emergency contraceptive?
Inhibits ovulation if taken within 72 hours of unprotected sex
- N&V - if within 3 hours repeat dose
- Reduced efficacy if taken with enzyme inducing drugs
- Women >70kg or BMI >26 need double dose
How does ulipristal acetate 30mg work as an emergency contraceptive?
Inhibits/delays ovulation if taken within 120 hours of unprotected sex
- N&V - if within 3 hours repeat dose
- Reduced efficacy if taken with enzyme inducing drugs
- Reduced efficacy with drugs that increase gastric pH
- Not suitable for women taking oral corticosteroids for asthma
- Cannot use with contraceptives - pharmacodynamic interaction - wait 5 days before starting restarting contraceptive
Which drugs induce CYP P450?
Rifampin, St John’s wort, Carbamazepine, Phenytoin
Cause increased clearance of contraceptive (CHC, POP, Imolant and EHC) - ineffective
What drugs inhibit CYP P450?
Erythromycin, Fluoroquinolones, ketoconazole, colchicine
Cause increased exposure increasing the risk of toxicity and VTE and exposure to other drugs
What causes reduced absorption of EHC?
- Vomiting and diarrhoea
- Drugs which alter gastric transit
- Drugs which alter gastric pH
- Chelating drugs
How do condoms work?
- provide a barrier to ejaculate, pre-ejaculate secretions and cervicovaginal secretions
- prevent fertilisation and reduce the risk of STI
- male - 18% failure
- female - 21%
How do diaphragms and caps work?
- 92% - 96% effective with correct use
- shallow rubber cup
- spermicide is inserted into the diaphragm and then placed in the vagina
- covers the cervix - must remain in place up to 6 hours after sex
- must be fitted by a trained HCP
- refitted if you gain/lose more than 3kg, have a baby, miscarriage or absorption
- not suitable if you have an unusually shaped cervix, history of TSS or UTI and allergy to latex or spermicide
How does spermicide work?
- gygel contains 2% nonoxynol-9
- acts as a surfactant dissolving the lipids in the sperm cell membrane killing sperm
- not adequate contraception alone
- discourage use of condoms coated with spermicide as they increase risk of genital lesions in the rectum and vaginal and can increase HIV and other STI transmission
- advocate use with diaphragm and caps
- irritant to the vaginal tissue and can lead to UTI
How does female sterilisation work?
- operation to permanently prevent pregnancy
- fallopian tubes are blocked or sealed preventing the egg reaching the sperm to be fertilised
- doesn’t affect hormone levels and periods still happen
- patient requires contraception before and up to 3 months after
- blocked fallopian tubes can re-join ectopic pregnancy
- 99% effective
- lifetime failure (0.5%)
How does a vasectomy work?
- undertaken under local anaesthetic
- scalpel method - two incisions in scrotak skin to expose vas deferents which is then occluded and divided
- minimally invasive - puncture wound in scrotakl skin and vas deferens occluded
- lifetime failure - (0.05%)
- contraception continued until 3 months after
- doesn’t increase risk of impotence, testicular cancer or HD
What is else is norethisterone used for?
A Progestogen that delays menstriation in someone not taking hormonal contraception
5mg TID for 3-4 weeks
What else is medroxyprogesterone used for?
A Progestogen used to delay menstruation
10mg BD or TDS
What else is mifepristone used for?
An anti Progestogenic steroid that sensitises the myometrium to prostaglandin-induced contractions and ripens the cervix for labour induction or termination of pregnancy
What else is misoprostal used for?
A synthetic prostaglandin analogue that is a potent uterine stimulant used for the termination of pregnancy (pv) and to prevent and treat gastric and duodenal ulcers
