7.1
Types of IUDs
Intrauterine device (IUD) is a small, flexible
plastic frame to be inserted into the uterine cavity.
Inert or non-medicated
These devices are made of plastic or stainless
steel only. Lippes loop made of plastic (polyethylene) impregnated
with barium sulphate is still used in many parts of the world. Stainless
steel rings are widely used in China only.
Copper IUDs
Copper wire or copper sleeves are put on
the plastic frame (polyethylene frame). Examples include Copper
T, CuT380 A, Multiload 375 etc.
The various types of Copper IUDs differ
from each other by the amount of copper. The initial Copper IUDs
were wound with 200-250 mm2 wire (CopperT 200). The modern copper
containing devices contain more copper and a part of copper in the
form of solid tubal sleeves rather than wire. This increases the
efficacy and lifespan (Cu T-380 A).
• CuT 380A - It is a T shaped
device with a polyethylene frame holding 380 mm2 of exposed surface
area of copper. The IUD frame contains barium sulfate thus making
it radio-opaque.
• CuT-380Ag - It is identical
to 380 A except that the copper wire on the stem has a silver core
to prevent fragmentation and extend the life span of the copper.
• CuT 380 slimline - It has
copper sleeves flushed at the ends of horizontal arms to facilitate
easier loading and insertion. The performance of CuT-380 Ag and
the CuT-380 slimline is equal to that of CuT-380 A.
• Multiload 375 - It has 375
mm2 of copper wire wound around its stem. The flexible arms are
designed to minimize expulsions. The multiload 375 and T cu-380
A are similar in their efficacy and performance.
• Nova T - It is similar to
the CuT-200, containing 200 mm2 of copper. However, the Nova T has
a silver core to the copper wire, flexible arms, and a large flexible
loop at the bottom to prevent cervical perforation.
Hormone-Releasing IUDs
• Progestasert - It is a
T shaped IUD made of ethylene and vinyl acetate copolymer containing
titanium dioxide. The vertical stem contains a reservoir of 38 mg
progesterone together with barium sulfate dispersed in silicone
fluid. The progesterone is released at the rate of 65 µg per day.
• LNG - 20 (Mirena) - This
T shape & device has a collar attached to vertical arm containing
52 mg of levonorgestrel dispersed in poly dimethyl siloxane. It
releases 15µg of levonorgestrel per day in vivo and is effective
for 7-10 years..
7.2 Mechanism of action
IUD
mainly work by changing the intra-uterine environment and making
it spermicidal. Non-medicated IUD cause a sterile inflammatory response
by producing a tissue injury of minor degree but sufficient enough
to be spermicidal.
Copper containing IUD, in addition, release
free copper and copper salts that have both a biochemical and morphological
impact on the endometrium and also produce alteration in cervical
mucus and endometrial secretions. No measurable increase in serum
copper is observed.
Hormone releasing IUD add progesterone effect
on endometrium to the foreign body reaction. The endometrium becomes
decidualized with atrophy of glands. The progesterone IUD does not
increase the serum progesterone level
and mainly acts by inhibition of implantation, sperm-capacitation
and survival. Levonorgestrel IUD produces serum concentrations of
the progestin half those of Norplant and therefore, ovarian follicular
development and ovulation is
not inhibited. The LNG-20 IUD decreases the blood loss (by about
40-50%) and dysmenorrhoea.
7.3 Efficacy
Table
II. First year clinical trial experience in parous women8
Device |
Pregnancy
rate (%) |
Expulsion
rate (%) |
Removal
rate (%) |
Lippes Loop
|
3 |
12-20 |
12-15 |
CuT-200 |
3 |
8 |
11 |
CuT-380
A |
0.5-0.8 |
5 |
14 |
Progesterone IUD |
1.3-1.6 |
2.7 |
9.3 |
Levonorgestrel IUD
|
0.2 |
6 |
17 |
|
7.4 Contraindications
•
pregnancy
• puerperal sepsis or immediate post septic
abortion
• distorted uterine cavity (congenital
or acquired)
• unexplained vaginal bleeding
• suspected genital malignancy
• high-risk candidate for STI
• genital tuberculosis
• active Pelvic Inflammatory Disease (PID)
+ Specific
contraindications to LNG-20
IUD
• current deep vein thrombosis/pulmonary
embolism
• current or past history of ischaemic
heart disease
• migraine with focal neurological symptoms
(at any age)
• current and past history of breast cancer
• active viral hepatitis, cirrhosis of
liver and benign or malignant liver tumors
7.5 Timing
of Insertion
After
childbirth
• immediately after delivery of placenta
(post-placental insertion)
• four to six weeks after childbirth
After spontaneous or induced abortion
• immediately after 1st trimester abortion
(aseptic).
• after 2nd trimester abortion it is advisable
to wait till involution of uterus is complete.
Menstrual cycle
• can be inserted any time, during menstrual
cycle, if reasonably sure that woman is not pregnant and has not
been having sex without contraception.
• insertion during menstruation
offeres following advantages :
– pregnancy is ruled out
– insertion is easier due to open
cervical canal
– any minor bleeding caused by insertion
is less likely to upset the client
7.6 Information to the client
after Copper
T insertion
• she can expect some cramping for a day
or two after insertion, vaginal discharge for a few weeks after
insertion and slightly heavier menstrual period with possible
bleeding between the menstrual periods during first few months
after insertion
•
follow-up visit after 3-6 weeks or after next menstrual period
to ensure that IUD is in place and no infection has developed.
• information about kind of IUD and when
to have her IUD removed or replaced.
+ when she
should see a nurse or doctor
after IUD insertion?
– missed menstrual period
– lower abdomen pain / vaginal discharge
/ fever
– missing IUD string
– very heavy and prolonged bleeding that
bothers her
Emergency Cotraception
should be used as ‘back up’ if IUD is expelled or misplaced.
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