Y4 Contraception Flashcards
Issues with barrier contraception:
Imperfect use.
Decreased arousal / discomfort.
Mechanism of action of the COCP:
Combined hormonal contraceptives act primarily to inhibit ovulation due to the negative feedback effect of the oestrogen and progesterone on the hypothalamo-pituitary axis. This prevents the surge in LH thus preventing ovulation. The progesterone also acts to inhibit proliferation of the endometrium, creating unfavourable conditions for implantation and increases the thickness of cervical mucus, preventing passage of sperm.
The period free of hormones, (pill-free break or taking placebos) causes a fall in hormonal concentration which leads to degeneration of the endometrium and menstrual bleeding.
Outline of the different types of COCP:
(just read)
- Monophasic pills:every pill contains the same levels of oestrogen and progesterone.
- Phasic pills:the level of oestrogen and progesterone in the pills changes throughout the cycle.
Packets either come in 21 (with a 7 day break) or 28 with no break.
Example of monophasic COCP:
(both include the 7 day break)
Microgynon
Brevinor
Explain the contraceptive patch for an OSCE:
The contraceptive patch is a form of combined hormonal contraception, it can be stuck onto the upper arm, abdomen, buttock or back to prevent pregnancy.
The patch used in the UK is brandedOrtho Evra.
These hormones work in the same way as the COCP by preventing ovulation, thinning the endometrial lining and thickening cervical mucus.
The patch is applied and changed every 7 days over a period of 3 weeks (21 days in total) and then the patch is removed for 7 patch-free days where the individual will usually experience a withdrawal bleed.
The patch is extremely sticky and can be used whilst bathing and swimming.
Explain the contraceptive vaginal ring for an OSCE:
The vaginal ring (NuvaRing®) is a combined hormonal contraceptive method.
The plastic ring is inserted into the vagina.
Once inserted the ring sits in the vagina for 21 days. It is then removed for 7 days before inserting the new ring.
Some women however may feel uncomfortable inserting or removing the ring.
Advantages of the combined hormonal contraceptive:
- Non-invasive
- More effective than barrier methods if taken correctly
- Sex doesn’t need to be interrupted to use contraception
- Menses tends to become regular, lighter and less painful, also allowing for control over timing of menses
- Reduced risk of cancer of the ovary, uterus and colon
- Reduced risk of functional ovarian cysts
- Normal fertility returns immediately after stopping usage.
Disadvantages of combined hormonal contraception.
- Some temporary adverse effects such as headaches, breast tenderness and mood changes can be experienced by some women
- Blood pressure may increase
- Women may experience breakthrough bleeding and spotting for the first few months
- Increased risk of venous thromboembolism
- Small increase in risk of myocardial infarctions and strokes
- Small increase risk of breast and cervical cancer
Contraindications to taking combined hormonal contraception:
- BMI greater than 35
- Breast feeding
- Smoking over the age of 35
- Hypertension
- History of or family history of venous thromboembolisms
- Prolonged immobility due to surgery or disability
- Diabetes mellitus with complications e.g. retinopathy
- History of migraines with aura
- Breast cancer or primary liver tumours
Key points regarding combined hormonal contraception for OSCE’s:
- Doesn’t protect against STI’s counsel on this.
- Missed pills counselling
- Think about adv, disadv and contra-indications.
What are the different types of emergency contraception?
Morning after pill (either Levongestrel e.g Levonelle one step or Ulipristal acetate e.g EllaOne).
Intrauterine Device (Cu-IUD).
Explain the use of Levonorgestrel aka Levonelle One Step as emergency contraception:
- How does it work?
- How long after an UPSI is it licensed for?
Levonorgestrel(1.5mg tablet) - marketed as Levonelle One Step.
Synthetic progesterone
Current evidence indicates that it can delay ovulation for 5 to 7 days, after which any sperm will have become non-viable.
- minus 14 days from cycle to make sure it’s given before ovulation
Licensed for use within 72 hours of unprotected sex.
Explain the use of Ulipristal acetate aka EllaOne as emergency contraception:
- How does it work?
- How long after an UPSI is it licensed for?
Ulipristal acetate(30mg tablet) - marketed as EllaOne.
Progesterone receptor modulator
Current evidence indicates that it can delay ovulation for 5 to 7 days, after which any sperm will become non-viable.
Licensed for use within 120 hours of unprotected sex.
- normal cycle minus 14 days
What are the cautions / contraindications for Levonogestrel?
There are no absolute contraindications to the use of levonorgestrel. However efficacy may be reduced by:
- Diseases of malabsorption e.g. Crohn’s
- BMI > 26 or weight >70kg
- Enzyme inducing drugs e.g. rifampicin
- If patient refuses IUD, then double dose i.e.3mgat oncemay be taken
Contraindications for ulipristal acetate:
- Diseases of malabsorption e.g. Crohn’s
- Hypersensitivity to Ulipristal Acetate
- Severe hepatic dysfunction
- Enzyme inducing drugs e.g. rifampicin
- Give 3mg levonorgestrel if the patient refuses an IUD, ulipristal acetate isabsolutelycontraindicated here
- Breast feeding –avoid breastfeeding for 7 days after taking UPA
- Asthma insufficiently controlled by corticosteroids
- Drugs increasing gastric pH e.g. omeprazole, ranitidine
