Contraception Flashcards
What are the types of hormonal contraception?
Combined hormonal contraceptives:
Contain both oestrogen and progesterone.
Available as tablets and patches.
Progesterone only contraceptives:
Contain only a progesterone of which there are many different types, including both natural and synthetic options.
Progesterone only pills.
Parenteral preparations e.g. depot injection, implant.
Intrauterine devices (the coil – available as a progesterone releasing or copper option).
What factors must be taken into consideration when giving contraceptives?
Age of the patient.
Medical history – including any interacting drugs, co-morbidities, risk factors, BP and BMI.
Family history.
Lifestyle and social factors such as smoking.
What are the advantages and disadvantages of combined hormonal contraceptives?
Advantages:
Reliable when taken as instructed.
Reversible.
Can reduce dysmenorrhea.
Can reduce incidence of pre menstrual tension (PMT).
Can help with fibroids and ovarian cysts.
Reduce risk of ovarian and endometrial cancer and pelvic inflammatory disease.
Disadvantages:
Can only be used up until the age of 50 – after this age women should be switched to a progesterone only or non hormonal method due to an increased risk of stroke and venous thromboembolism with age.
Less effective than long acting reversible progesterone only methods - mainly due to more opportunity of user error via missed pills.
There may be a short delay in return to fertility with patches but not with tablets.
What are the advantages of extended cycling and tailored regimes?
Reduce withdrawal symptoms.
Reduce risk of escape ovulation.
Therefore reduce risk of pregnancy.
They have been shown to be safe and effective for contraception.
However, unscheduled bleeding is common when using these regimes.
What are the contraindications and cautions of combined hormonal contraceptives?
Contraindications:
Migraine with aura (increased risk of stroke).
Personal history of venous or arterial thrombus.
Current breast cancer.
>35 and smoking 15 or more cigarettes daily.
Atrial fibrillation.
Stroke.
Cautions:
Family history of VTE (specifically for VTE risk).
Obesity.
Age > 40.
Smoker.
Hypertension.
Migraine (specifically a risk for CV/arterial disease).
What are the risks of combined hormonal contraceptives?
Small increase in risk of cervical and breast cancer which returns to normal 10 years after stopping.
Reduced risk of ovarian and endometrial cancer for several decades after stopping.
Increased risk of venous thromboembolism (VTE):
Absolute risk is still very low and considerably less than in pregnancy.
Risk higher in first year and if restarting after a break of >4 weeks.
Very small increased risk of ischaemic stroke and MI - absolute risk is very low in women of reproductive age.
What are the advantages and disadvantages of progesterone only contraceptives?
Advantages:
Fewer contraindications and therefore useful in women contraindicated to combined pills.
Ovulation in inhibited in up to 97% of cycles.
There is a 12 hour window for missed pills as opposed to 3 hours for traditional progesterone pills.
Disadvantages:
Cause irregular bleeding in the first few months which is usually transient and eventually leads to amenorrhoea in many women.
What are the contraindications of progesterone only contraceptives?
Current breast cancer (may be used after 5 years).
Acute porphyrias.
What are the advantages and disadvantages of long acting reversible contraception (LARC)?
Advantages:
Good long term options with a very low failure rate as compared to oral methods which have potential for user error (i.e. missed pills).
Disadvantages:
Potential for some delay in return to fertility with some options.
Can initially cause irregular bleeding but in most cases lead to amenorrhoea eventually.
What is medroxyprogesterone acetate?
Long acting progesterone given by IM injection.
Can be used in the short (months) or longer term (up to 2 years).
Women should be counselled about the likelihood of menstrual disturbance and a potential for delay in return to full fertility.
Irregular cycles can occur for a time when treatment ends.
What is etonogestrel?
Implant that releases etonogestrel slowly over a period of years.
Consists of a flexible rod inserted into the underside of the upper arm where it can remain for up to three years.
Very effective and causes few side effects.
Can cause some local reactions at injection site.
Return of fertility achieved rapidly following implant removal.
What is a intra-uterine system?
Release levonorgestrel directly into the uterine cavity.
Very effective for contraception and can also be used for menorrhagia and prevention of endometrial hyperplasia.
Release of progesterone leads to prevention of endometrial proliferation, thickening of cervical mucus and may suppress ovulation in some women in some cycles.
Device itself may also contribute to contraceptive effect.
Return of fertility generally rapid and complete.
Why can’t you use antiepileptics with contraceptives?
Some antiepileptics can cause issues due to enzyme induction, however, some also carry a significant risk of teratogenicity.
Valproate has the highest risk and women of child bearing age on valproate must be on a pregnancy prevention programme and use a highly effective method of contraception e.g. a LARC.
If needed during pregnancy should maintain on lowest possible dose and carefully monitor.
Levetiracetam and lamotrigine are safer and evidence does not appear to indicate an increased risk of major congenital malformations.
Combined hormonal contraceptives can modestly reduce exposure to lamotrigine.
May need to increase lamotrigine dose or consider extended pill taking.
What are the risks of hormonal contraception?
There is an increased risk of venous thromboembolism when using combined hormonal contraceptives especially in the first year and when restarting after a break of > 4 weeks.
Small increased risk of breast cancer with combined but the cancer is more likely to be localised. Related to age at which stopped rather than duration of use. Risk level decreases during the 10 years after stopping to normal.
Evidence for increased breast cancer risk with progesterone only less clear but may be a small increased risk.
Small increased risk of cervical cancer when combined hormonal contraceptive used for more than 5 years. Risk decreases after stopping and returns to normal by 10 years.
Decrease in risk of ovarian and endometrial cancer.
