The document discusses the anatomy of the human uterus and provides details on intrauterine devices (IUDs). It describes the historical background of IUDs, their mechanisms of action including morphological and biochemical changes in the endometrium, as well as potential complications. The summary is as follows:
[1] The document discusses the anatomy of the human uterus and historical background of intrauterine devices (IUDs) for birth control.
[2] IUDs prevent pregnancy primarily by interfering with sperm viability and mobility through morphological and biochemical changes in the endometrium as well as copper ion release.
[3] Potential complications of IUDs include pelvic inflammatory disease risk with
2. Introduction.
Anatomy of Human Uterus.
The Intrauterine Devices.
Historical Background
Estimated extend Of Use
Mechanism Of Action
Morphological & Biochemical Endometrial Change By IUD
Complications
3. The uterus function mainly as a reproductive organ harboring
the developing embryo and fetus.
Rich in blood supply, so potential organ for systemic drug
administration.
Intrauterine devices, being easily inserted into uterine cavity
for long periods & having minimal complications, suggested as
possible vehicle for this purpose.
To use the uterine cavity for systemic drug delivery, the
important parameter to be known are uterine anatomy,
physiology & histology.
4. Uterus is hollow, pear shaped fibromuscular organ whose
shape, weight & dimension vary considerably
Depending upon both estrogenic stimulation & previous birth
or parturition.
The function of uterus is to house & nourish the embryo &
fetus and birth by applying powerful contraction of its thick
muscular walls
In young nulliparous adult it measures 8cm long, 5cm width
and 2.5cm thick, weigth around 30-40g
Between birth and puberty the uterus descends gradually
from lower abdomen to true pelvis.
5. • After puberty it located in the midline in true pelvis behind
symphysis pubis & urinary bladder and in front of rectum.
• The uterus has 2 portions, an upper muscular corpus & lower
fibrous cervix.
• Internal os is a slight constriction corresponding to narrowing
of the cavity & part above it is corpus while below it is cervix.
• Fundas is nothing but portion of corpus that extends above
insertions of fallopian tubes.
• In reproductive women, the corpus is considerably larger than
the cervix, but before menarche, and after menopause, their
size are similar.
6. • In coronal section it is triangular, its base being formed by the
internal fundal surface between the openings of the uterine
tubes; its apex is the internal os, leading to the cervical canal.
7.
8. • The intrauterine device is highly effective in preventing the
pregnancy.
• The first IUD used specifically for contraception was described
by Richter in 1909. It was a ring made of silkworm gut
• Graefenberg in 1931 describe that core of silkworm gut
encircled by alloy of copper, nickel & zinc highly effective in
preventing pregnancy.
• Early devices had local success but general medical opinion
prevented their large scale adoption.
9. • In 1960, the first of the so called “second generation” IUDs
represented by “Margulies spiral” was introduced.
• This device was made of plastic without metal but with barium
sulfate being added to the plastic to render its radio opaque (
dense material that prevent electromagnetic passage).
• In 1962, Lippes loop, which is still one the most widely used
IUDs. This IUD was the first to have a nylon thread attached to the
lowest part of the device; facilate easily removal form uterine
cavity.
10.
11. • Using a T carrier with addition of 200mm2 copper wire
reduced the pregnancy rate 18% in women year with plain T
carrier to 1% women year.
• A number of copper bearing devices are now commercially
including the copper-7 & copper-T in various other forms.
• Scommegna et al, developed the hormone releasing devices
and showed that it is effective in preventing pregnancy as the
copper-bearing IUD.
• The progestasert is a T shaped device, consisting of a
permeable polymer membrane which releases progesterone at
a predictable, controlled rate of 65 micro g per 24 hr over a
period of a year.
12.
13. • Similar devices containing large amounts of progestrone that is
released at a lower rate, were expected to be effective for 3-5 yrs,
but found to be effective life span for 1.5-2yrs
• A new hormone releasing device with shape based on that of
the Nova-T IUD, releasing 20µg/day levonorgestrel from a
reservoir in the form of polydimethylesiloxane collar ( silicon
polymer) gives a low pregnancy rate i.e. 0.3% at 1 yr, with
significant reduction in blood loss during menstrual.
• Reduction in pain during menstruation but an increase
discontinuation rate on account of amenorrhea (up to 10%) (
absence of menstrual cycle in reproductive women ).
14. • Intrauterine devices (IUDs) prevent fertilization primarily by
interfering with the ability of sperm to survive and to ascend the
fallopian tubes, where fertilization occurs.
• Having a foreign body in the uterus, such as an IUD, causes
both anatomical and biochemical changes that appear to be toxic
to sperm. Studies have generally found that sperm are not as
viable among IUD users, compared to other women.
•When a foreign body (IUD) is in the uterus, the endometrium
reacts by releasing white blood cells, enzymes and
prostaglandins; and these reactions of the endometrium appear to
prevent sperm from reaching the fallopian tubes.
15. • In addition, copper-bearing IUDs release copper ions into the
fluids of the uterus and the fallopian tubes, enhancing the
debilitating effect on sperm.
• Evidence for these mechanisms includes physical examination
of women's eggs. When an ovum is fertilized, it begins to produce
human chorionic gonadotropin (hCG) near the time of
implantation.
• A 1987 study to monitor hCG production in 40 women using
IUDs found only one probable fertilized egg among 107 cycles.
• "Whatever the IUD's specific mechanism of action, it appears
that the IUD effectively interrupts the reproductive process before
implantation," the study concluded.
16. • Half of the women using no
contraception who had intercourse
during the fertile period had ova that
were consistent in appearance with
fertilized eggs.
• In contrast, none of the ova taken
from copper IUD users who had
intercourse appeared to be fertilized.
Also, no ova were found in the
uterus of any of the copper IUD
users.
• "IUDs exert effects that extend
beyond the body of the uterus
and interfere with steps of the
reproductive process that take
place before the eggs reach the
uterine cavity,"
17. • The levonorgestrel IUD, called an intrauterine system, uses
different mechanisms. Like other progestin methods, this device
prevents pregnancy primarily by thickening cervical mucus, which
inhibits the ability of sperm to enter the uterus.
18. • Morphological & biochemical endometrial changes caused by
IUD are that whenever a foreign body is introduced into the
uterine cavity.
• The biochemical & cellular changes reaction take place,
characterized by specific changes in endometrial tissue.
• Increased vascular permeability, edema, and stromal infiltration
of leukocytes, including neutrophils, mononuclear cells and
macrophages have been seen.
• In the normal menstrual cycle, extensive leukocyte infiltration
occur about 24-48hr prior to the onset of menstruation.
19. • It should be emphasized that the foreign body reaction seen
with both medicated and non medicated IUDs occurs in the
absence of bacterial infection & especially in the area adjacent to
the device.
• The foreign body reaction should not be confused with the
endometritis, which is a bacterial inflammatory condition.
• The high levels of intrauterine protein reported in IUD users
might reflect the cellular degradation of these neutrophils &
macrophages and thereby further contribute to anti fertility effect.
• The foreign body reaction caused by non medicated devices are
enhanced by addition of copper to the IUD.
20.
21. • Insertion of the IUD may introduce bacteria into the uterus. The
insertion process carries an increased risk of pelvic inflammatory
disease in the first 20 days following insertion.
• It is very important that the provider use proper infection-
prevention techniques during insertion.
• Some barrier contraceptives protect against STDs. Hormonal
contraceptives reduce the risk of developing pelvic inflammatory
disease (PID), a serious complication of certain STDs. IUDs, by
contrast, do not protect against STDs or PID.
• During the placement appointment, the cervix is dilated in order
to sound (measure) the uterus and insert the IUD. Cervix dilation
can be uncomfortable and, for some women, painful.
22. • Taking NSAIDS before the procedure can reduce discomfort, as
can the use of a local anaesthetic. Misoprostol 6 to 12 hrs before
insertion can help with cervical dilatation.
• After IUD insertion, menstrual periods are often heavier, more
painful, or both - especially for the first few months after they are
inserted. On average, menstrual blood loss increases by 20–50%
after insertion of a copper-T IUD; increased menstrual discomfort
is the most common medical reason for IUD removal.
• The string(s) may be felt by some men during intercourse. If this
is problematic, the provider may cut the strings even down to the
cervix, so they cannot be felt. Shortening the strings does prevent
the woman from checking for expulsion
• Non-hormonal (copper) IUDs are considered safe to use while
breastfeeding.