Progesterone-Only Injection & Implant Flashcards
What is involved in the progesterone-only injection?
- a SC or IM injection is given every 12-13 weeks
- the injection contains medroxyprogesterone acetate
- it is also referred to as DMPA
How does medroxyprogesterone acetate affect return of fertility?
- it can take up to 12 months for fertility to return to normal after stopping the injection
- this makes it less suitable for women wishing to get pregnant in the near future
What are the 2 commonly used versions of the injection?
Depo-Provera:
- given as an intramuscular injection
Sayana Press:
- a subcutaneous injection that can be self-administered
they both contain medroxyprogesterone acetate
What is noristerat and when is it used?
- an alternative injection containing norethisterone
- it works for 8 weeks
- it is used as short-term interim contraception, such as after a partner has had a vasectomy
What are the UK MEC 4 criteria for using the injection?
active breast cancer
What are the UK MEC 3 criteria for using the injection?
- ischaemic heart disease / stroke
- severe liver cirrhosis / cancer
- unexplained vaginal bleeding
What must be considered in older women requesting the injection?
- it can cause osteoporosis
- this is significant in older women + patients on steroids for asthma / inflammatory conditions
- it is UK MEC 2 in women > 45 and they should switch to an alternative by age 50
What must be considered in older women requesting the injection?
- it can cause osteoporosis
- this is significant in older women + patients on steroids for asthma / inflammatory conditions
- it is UK MEC 2 in women > 45 and they should switch to an alternative by age 50
What is the mechanism of action of the DMPA?
inhibition of ovulation:
- it inhibits FSH secretion by the pituitary gland
- this prevents the development of follicles in the ovaries
other actions:
- thickening of cervical mucus
- altering the endometrium to make it less accepting of implantation
What advice is given regarding condom use when starting the DMPA injection?
- no additional protection is required if started on day 1 - 5 of the cycle
- if started at any other time, condoms should be used for 7 days
What do the guidelines state about the frequency of injections?
women need to have injections every 12-13 weeks
- it can be given as early as 10 weeks
- and it can be given as late as 14 weeks where necessary (but this is not licensed)
What are the 2 side effects that are unique to the injection?
osteoporosis & weight gain
What are women told about their bleeding pattern prior to starting the injection?
- with any progesterone-only contraception, changing to the bleeding schedule is common
- it cannot be predicted how the woman will respond
- bleeding may become irregular, heavier or prolonged (usually temporary)
- most women will stop bleeding altogether** after **1 year of use
What are the side effects associated with the DMPA injection?
- weight gain
- acne
- reduced libido
- mood changes
- headaches / flushes
- alopecia (hair loss)
- skin reactions at injection sites
- OSTEOPOROSIS
Why can the DMPA injection cause osteoporosis?
- oestrogen helps to maintain bone mineral density
- oestrogen is mainly produced by the follicles in the ovaries
- suppressing the development of follicles reduces the amount of oestrogen produced
- this results in decreased bone mineral density
What are the benefits associated with the injection?
- improvement in dysmenorrhoea
- improvement in endometriosis-related symptoms
- reduces severity of sickle cell crisis in sickle cell anaemia
Where is the progesterone-only implant positioned?
- it is placed in the upper arm
- it is beneath the skin and above the subcutaneous fat
- it slowly releases progestogen into the systemic circulation
What implant is used in the UK?
What does it contain and who can have it?
Nexplanon
- it contains 68mg etonogestrel
- it is licensed for use between the ages of 18 and 40
How is the implant inserted and its position checked?
- lidocaine is used as a local anaesthetic
- a special device is used to insert the implant horizontally, beneath the skin and above the subcutaneous fat
- it is inserted ⅓ of the way up the upper arm, on the medial side
- it should be palpable immediately
- pressing on one end of the implant should make the other end pop up against the skin
How is the Nexplanon implant removed?
- lidocaine is used
- a small incision is made in the skin at one end of the implant
- the device is removed using pressure on the other end or forceps
What advice is given to women about palpating their implant?
- women should palpate the implant occasionally
- if the implant becomes impalpable, extra contraception is required until it is located
- USS or XR can be used to locate the implant as it contains barium sulphate
- referral to a specialist removal centre may be required
If the implant cannot be detected after USS, what should be done?
CXR
- rarely, the implant can enter blood vessels and migrate through the body
- there is a risk of an implant entering a pulmonary artery
