Intrauterine_Contraceptive_Devices_Flashcards

Question 1

What types of intrauterine contraceptive devices (IUDs) are there?

Answer 1

Conventional copper intrauterine devices (IUDs) and levonorgestrel-releasing intrauterine systems (IUS, Mirenaµ).

Question 2

How effective are IUDs and IUSs?

Answer 2

Both are more than 99% effective.

Question 3

What is the primary mode of action of an IUD?

Answer 3

Prevention of fertilisation by causing decreased sperm motility and survival (possibly an effect of copper ions).

Question 4

What is the mode of action of an IUS?

Answer 4

Levonorgestrel prevents endometrial proliferation and causes cervical mucous thickening.

Question 5

When can an IUD be relied upon following insertion?

Answer 5

Immediately following insertion.

Question 6

For how long are the majority of IUDs effective?

Answer 6

5 years for those with copper on the stem only, and up to 10 years for those with copper on the stem and the arms of the T.

Question 7

When can an IUS be relied upon following insertion?

Answer 7

After 7 days.

Question 8

For how long is the Mirenaµ IUS effective?

Answer 8

5 years, but only licensed for 4 years if used as endometrial protection for women taking oestrogen-only hormone replacement therapy.

Question 9

What are the potential problems with IUDs?

Answer 9

Make periods heavier, longer, and more painful.

Question 10

What are the potential problems with IUSs?

Answer 10

Initial frequent uterine bleeding and spotting, later intermittent light menses with less dysmenorrhoea, and some women become amenorrhoeic.

Question 11

What is the risk of uterine perforation with IUD/IUS?

Answer 11

Up to 2 per 1000 insertions, higher in breastfeeding women.

Question 12

How does the risk of ectopic pregnancy compare with IUD/IUS use?

Answer 12

The proportion of pregnancies that are ectopic is increased, but the absolute number of ectopic pregnancies is reduced compared to a woman not using contraception.

Question 13

What is the risk of pelvic inflammatory disease after IUD insertion?

Answer 13

There is a small increased risk in the first 20 days after insertion, but after this period, the risk returns to that of a standard population.

Question 14

What is the risk of IUD/IUS expulsion?

Answer 14

Around 1 in 20, most likely to occur in the first 3 months.

Question 15

What are the new IUS systems?

Answer 15

Jaydessµ (licensed for 3 years, smaller frame, less LNG), Kyleenaµ (licensed for 5 years, smaller than Mirenaµ, lower serum levels of LNG, less amenorrhoea compared to Mirenaµ).

Question 16

Summarise intrauterine devices

Answer 16

Intrauterine contraceptive devices

Intrauterine contraceptive devices comprise both conventional copper intrauterine devices (IUDs) and levonorgestrel-releasing intrauterine systems (IUS, Mirenaµ). The IUS is also used in the management of menorrhagia

Effectiveness
both the IUD and IUS are more than 99% effective

Mode of action
IUD: primary mode of action is prevention of fertilisation by causing decreased sperm motility and survival (possibly an effect of copper ions)
IUS: levonorgestrel prevents endometrial proliferation and causes cervical mucous thickening

Counselling
IUD
can be relied upon immediately following insertion
the majority of IUDs with copper on the stem only are effective for 5 years, whereas some of the IUDs that have copper on the stem and the arms of the T may be effective for up to 10 years
IUS
can be relied upon after 7 days
the most common IUS (i.e. Mirenaµ - levonorgestrel 20 mcg/24 hrs) is effective for 5 years
if used as endometrial protection for women taking oestrogen-only hormone replacement therapy they are only licensed for 4 years

Potential problems
IUDs make periods heavier, longer and more painful
the IUS is associated with initial frequent uterine bleeding and spotting. Later women typically have intermittent light menses with less dysmenorrhoea and some women become amenorrhoeic
uterine perforation: up to 2 per 1000 insertions and higher in breastfeeding women
the proportion of pregnancies that are ectopic is increased but the absolute number of ectopic pregnancies is reduced, compared to a woman not using contraception
infection: there is a small increased risk of pelvic inflammatory disease in the first 20 days after insertion but after this period the risk returns to that of a standard population
expulsion: risk is around 1 in 20, and is most likely to occur in the first 3 months

New IUS systems

The Jaydessµ IUS is licensed for 3 years. It has a smaller frame, narrower inserter tube and less levonorgestrel (LNG) than the Mirenaµ coil (13.5 mg compared to 52 mg). This results in lower serum levels of LNG.

The Kyleenaµ IUS has 19.5mg LNG and is also smaller than the Mirenaµ but is licensed for 5 years. It also results in lower serum levels of LNG. The rate of amenorrhoea is less with Kyleenaµ compared to Mirenaµ.

Question 17

A 27-year-old female asks for advice regarding the Mirena (intrauterine system). What is the most likely effect on her periods?

Continual, light bleeding is seen in 70%
Initially irregular bleeding later followed by periods that are generally heavier and longer
Heavy period approximately every 3 months
Amenorrhoea in > 90% after 2 months
Initially irregular bleeding later followed by light menses or amenorrhoea

Answer 17

Initially irregular bleeding later followed by light menses or amenorrhoea

The correct answer to this question is Initially irregular bleeding later followed by light menses or amenorrhoea. The Mirena intrauterine system (IUS) releases a small amount of the hormone levonorgestrel into the uterus each day. This can initially cause irregular bleeding or spotting, but over time it typically results in lighter periods or no periods at all (amenorrhoea). According to the Faculty of Sexual and Reproductive Healthcare guidelines, approximately 20% of women using a levonorgestrel-releasing IUS will experience amenorrhoea after one year.

Now let’s discuss why the other options are incorrect.

Continual, light bleeding is seen in 70%: This statement is inaccurate. While some women may experience light bleeding or spotting during the first few months after insertion of an IUS, continual light bleeding does not occur in 70% of users.

Initially irregular bleeding later followed by periods that are generally heavier and longer: This option is incorrect because one of the common effects of Mirena is to reduce menstrual flow rather than increase it. In fact, it’s often used as a treatment for heavy menstrual bleeding.

Heavy period approximately every 3 months: This choice is also incorrect. The Mirena IUS typically leads to lighter periods over time, not heavier ones. And while some women might experience infrequent heavy periods with certain types of birth control methods, this isn’t typically the case with Mirena.

Amenorrhoea in > 90% after 2 months: While amenorrhoea can occur with Mirena use, it doesn’t happen this quickly nor in such a high percentage of users. As mentioned earlier, about 20% of women will have no periods after one year.