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The levonorgestrel intrauterine device, which delivers a progestin
directly into the uterus, is not only a highly effective contraceptive,
but is proving to offer several noncontraceptive benefits. Because it
gradually releases levonorgestrel, its developer calls it an
intrauterine "system" or IUS instead of intrauterine device
(IUD).
Like the Copper T IUD, the IUS has a T-shape and is inserted into the
uterus. It releases 20 mcg of levonorgestrel daily, giving it qualities
similar to other progestin-only methods. The IUS's distinctive
noncontraceptive benefits are due to this hormonal feature.
Among the benefits are a substantial decrease in menstrual blood loss
and pain. The IUS also protects against the growth of fibroids, which
are noncancerous growths of uterine muscle that can cause painful and
heavy menstruation. It can stop the development of endometriosis, which
is the formation in the pelvis of tissue similar to the endometrium, or
uterine lining.
Ectopic pregnancies are very rare among women using the IUS, even
rarer than among women using no contraception or those using a Copper T
IUD. While data are conflicting and more research is needed, the IUS may
protect against pelvic inflammatory disease (PID). Finally, it can be
used with estrogen replacement therapy (ERT) during menopause to protect
the endometrium.
The noncontraceptive health benefits of modern methods are of
increasing interest to many women, especially since most modern methods
are considered to be both safe and effective.
The IUS may be as effective as female sterilization, considered to be
the most effective method available. The pregnancy rate at five years is
estimated to be from 0.5 to 1.1 per 100 women, according to
international studies involving some 3,000 IUS users.1 It is
1.3 per 100 women for female sterilization2 and 1.4 per 100
women for the Copper T 380A IUD.3 Furthermore, this low
pregnancy rate does not vary based upon the age of the user. Other
contraceptive methods have higher failure rates among women under the
age of 30 who tend to be more fertile and have sexual intercourse more
frequently than do older women.4
After IUS removal, fertility returns quickly. In two studies of
fertility recovery after IUS use, 80 percent of 138 users and 96 percent
of 60 users, respectively, became pregnant within the first year after
removal.5 Notably, women in these studies had the IUD removed
because they wished to become pregnant.
The IUS can be a good alternative to male or female sterilization for
couples who wish to have no more children. Although the device is
approved in the United Kingdom for five years of use, it may be
effective for at least seven years.6 Left in place through
menopause, it can be an important addition to ERT, which is used to
treat menopausal symptoms.
However, the device is relatively expensive and is not widely
available outside of Europe.
Bleeding and fibroids
Like other methods that use a progestin hormone, the IUS prevents
pregnancy primarily by thickening cervical mucus, which impedes sperm
entry into the uterus. The device suppresses ovulation in some cycles
and, like a copper IUD, may inhibit sperm motility and function.
Levonorgestrel also affects the endometrium, causing it to remain thin
and reducing the rare chance that a fertilized egg would be implanted.
Because endometrial growth is suppressed, users can expect a marked
reduction in the amount of menstrual blood loss. Initially, the device
tends to increase the number of days of bleeding or spotting. But, after
a few months of use, both amount and duration of bleeding decrease. Many
women experience little or no bleeding (amenorrhea) within a year.
By reducing menstrual blood loss, the IUS helps maintain the body's
iron reserves. This could be particularly important for women in
developing countries where high parity, poor nutrition and diseases can
easily result in iron deficiency.
In addition, the IUS protected against fibroid development in a
six-country study conducted by the Population Council that compared the
IUS and Copper T 380A. Over seven years, one of 1,125 women using an IUS
developed fibroids, compared with 14 of 1,121 women using the copper
IUD.7 Fibroids are the most common tumors found in women,
with one in five women (or approximately 225 of 1,125 women) developing
them by age 40.
"Whether use of the LNg IUD actually reduces the size of
preexisting fibroids has been investigated in only one small pilot
study," says Dr. Vera Grigorieva, an obstetrician and gynecologist
at the Ott Institute Family Planning Center in St. Petersburg, Russia,
and a former FHI fellow. Results of a study that Dr. Grigorieva is
conducting of IUS use among women with fibroids may help clarify the
issue.
Because the IUS is highly effective at preventing pregnancy in
general, its use rarely is associated with ectopic pregnancies
(estimated in one study to be one ectopic pregnancy in 5,000
woman-years).8 None occurred in a total of 3,416 woman-years
of IUS use in the six-country Population Council study comparing the IUS
with the Copper T 380A.9 Similarly, no ectopic pregnancies
occurred in 882 woman-years of IUS use in a three-year study by the
Indian Council of Medical Research (ICMR).10
However, like IUD users, women who receive the IUS should be told of
the possibility of an ectopic pregnancy (implantation of a fertilized
egg outside of the uterus, usually in a fallopian tube). A woman
receiving an IUS should be counseled to seek medical attention promptly
if she experiences signs of pregnancy, since it could be ectopic.
Ectopic pregnancies are life-threatening.
PID protection?
Data are conflicting as to whether the IUS provides some protection
against PID. This rare inflammation of a woman's upper genital tract can
lead to chronic pelvic pain, ectopic pregnancy and even death.
One group of investigators found in a five-year study that PID rates
were lower among 1,800 women with IUSs than among 900 women with copper
Nova T IUDs.11 The five-year removal rates for PID were 0.8
per 100 users in the IUS group, compared with 2.2 per 100 users in the
Copper T IUD group. The difference between groups was significant for
women younger than 25 years old. In general, young, sexually active
women are at greater risk of PID than older women who are sexually
active. A lower risk of PID associated in this study with the IUS,
compared with copper IUDs, is likely to be important to many young women
who are interested in protecting their future fertility.
Researchers have speculated that if the IUS protects against PID, the
protection may be due to thickened cervical mucus (blocking the passage
of pathogens into the uterus); endometrial suppression (reducing the
area that pathogens can infect); or reduced bleeding (decreasing the
chance that menstrual blood will flow backwards, carrying pathogens into
the fallopian tubes).
However, the six-country Population Council study comparing the IUS
with the Copper T 380A found no difference between five-year removal
rates attributable to PID and endometriosis (0.7 per 100 woman-years)
among 1,125 women using the IUS and 1,121 women using copper IUDs.12
Another study conducted by the ICMR in India did not find significant
differences after three years in PID-related removal rates between IUS
users and women who used various copper IUDs.13 Thus, further
research is needed to clarify this issue.
In terms of cancer risk, no differences in the incidence of breast or
cervical cancer were found at five years among IUS and Copper T 380A
users in the six-country study comparing the two devices.14
The incidence of cervical cancer was less than 0.1 per 100 women-years
for both devices. Breast cancer incidence was less than 0.1 per 100
woman-years for IUS users; no cases occurred among copper IUD users.
Several studies in India have shown that use of the IUS by
breastfeeding women for more than three months had no adverse effect on
the reproductive hormones, growth, or physical and mental well-being of
the women's infants.15
The IUS may be especially well suited for postabortion contraception.
A study of the menstrual diaries of some 300 Finnish women showed that,
among IUS users, postabortion insertion was associated with better
bleeding patterns (for example, fewer days of bleeding during the first
two months postinsertion) than postmenstrual insertion.16
Like other estrogen-free methods, the IUS may be a good contraceptive
choice for women with high blood pressure; diabetes with vascular
disease or diabetes for more than 20 years; epilepsy, or severe,
recurrent headaches with focal neurological symptoms; and women with a
history of, or currently experiencing, deep venous thrombosis or
pulmonary embolism.17
For HIV-positive women also, the IUS may be a good contraceptive
choice, although it offers no protection against HIV transmission or any
other sexually transmitted disease. Its use by infected women is not
restricted by World Health Organization (WHO) guidelines. It should not
be inserted in an HIV-positive woman with an AIDS-defining illness who
is infected with a sexually transmitted disease, such as chlamydia or
gonorrhea, since her suppressed immune system may make her particularly
vulnerable to PID.
Amenorrhea counseling
The IUS has a few known disadvantages. Progestin-related side effects
-- such as headache, nausea, acne, abnormal hairiness, depression and
other mood changes, and breast tenderness -- are uncommon and gradually
decrease over time. Persistent unruptured ovarian follicles (also known
as functional ovarian cysts) are slightly more common in the users of
progestin-only contraceptive methods (such as progestin-only pills and
subdermal implants), and can also occur with use of the device. They can
cause lower-abdominal discomfort, but are not harmful and generally
disappear without treatment a few weeks after IUS discontinuation.
Some women view IUS-related amenorrhea as an advantage. Other women,
however, may not tolerate the intermenstrual bleeding that often occurs
in the first months of use, or amenorrhea later. A multicenter WHO study
that involved some 3,400 women and compared the IUS with the Copper T
380A found, at three years of use, a 27 percent removal rate due to
amenorrhea for the IUS, compared with a 0.2 percent removal rate for the
Copper T 380A. Removal rates for pain or bleeding were 17 percent for
the IUS versus 11 percent for the Copper T 380A.18
A review of three other multicenter, international studies indicated
lower rates of discontinuation for IUS-related amenorrhea, ranging from
6 percent to 20 percent at five years among some 4,000 women.19
These differences in rates may reflect the design and execution of the
studies. Investigators in two of the studies, for example, knew which
device women were using and might have prepared some of the women for
the possibility of bleeding disturbances. Also, women in different
cultures react differently to menstrual changes.
That counseling can boost IUS continuation rates was demonstrated in
a study involving 381 women receiving the device in a clinic in
Campinas, Brazil, and 200 IUS users in Santo Domingo, Dominican
Republic. Brazilian researchers concluded that special emphasis placed
on good counseling in the Campinas clinic was one reason for a
significantly lower one-year IUS discontinuation rate in Campinas (18
per 100 IUS users) than in Santo Domingo (33 per 100 users).20
Key counseling messages are that the IUS is not harmful to health,
that menstrual blood loss serves no useful purpose, and -- given the
IUS's high efficacy -- that amenorrhea almost certainly is not a sign of
an unintended pregnancy.
-- Kim Best
References
- Sivin I, Stern J, Coutinho E, et al. Prolonged
intrauterine contraception: a seven-year randomized study of the
levonorgestrel 20 mcg/day (LNg 20) and the Copper T380 Ag IUDs. Contraception
1991;44(5):473-80; Andersson K, Odlind V, Rybo G.
Levonorgestrel-releasing and copper-releasing (Nova T) IUDs during
five years of use: a randomized comparative trial. Contraception 1994;49(1):56-72;
Allonen H. The levonorgestrel IUD. In Bardin CW, Mishell DR Jr.,
eds. Proceedings from the Fourth International Conference on IUDs.
(Newton, MA: Butterworth-Heinemann, 1994)287.
- Peterson HB, Xia Z, Hughes JM, et al. The risk of
pregnancy after tubal sterilization: findings from the U.S.
Collaborative Review of Sterilization. Am J Obstet Gynecol 1996;174(4):1161-70.
- Sivin, Stern, Coutinho; Allonen.
- Peterson; Luukkainen T, Toivonen J.
Levonorgestrel-releasing IUD as a method of contraception with
therapeutic properties. Contraception 1995;52(5):269-76.
- Andersson K, Batar I, Rybo G. Return to fertility
after removal of a levonorgestrel-releasing intrauterine device and
Nova T. Contraception 1992;46(6):575-84; Belhadj H, Sivin I,
Dķaz S, et al. Recovery of fertility after use of the
levonorgestrel 20 mcg/d or Copper T 380 Ag intrauterine device. Contraception
1986;34(3):261-67.
- Luukkainen T, Allonen H, Haukkamaa M, et al. Five
years' experience with levonorgestrel-releasing IUDs. Contraception
1986;33(2):139-48.
- Sivin I, Stern J. Health during prolonged use of
levonorgestrel 20 µg/d and the Copper TCu 380Ag intrauterine
contraceptive devices: a multicenter study. Fertil Steril 1994;61(1):74.
- Ojutiku D, Cutner A, Rymer J. Ectopic pregnancy
with levonorgestrel releasing intrauterine system. Br J Fam Plann
1998;24(2):85-86.
- Sivin, Stern.
- Indian Council of Medical Research, Task Force on
IUDs. Randomized clinical trials with intrauterine devices
(levonorgestrel intrauterine device, (LNg), CuT 380Ag, CuT 220C, CuT
200B). A 36-month study. Contraception 1989;39(1):37-52.
- Andersson, Odlind, Rybo.
- Sivin, Stern.
- Indian Council of Medical Research.
- Sivin, Stern.
- Toddywalla VS, Patel SB, Betrabet SS, et al.
Low-dose progestogen contraception and the nursing mother. Adv
Contracept 1995;11(4):285-94.
- Suvisaari J, Lähteenmäki P. Detailed analysis of
menstrual bleeding patterns after postmenstrual and postabortal
insertion of a copper IUD or a levonorgestrel-releasing intrauterine
system. Contraception 1996;54(4):201-8.
- World Health Organization. Improving Access to
Quality Care in Family Planning: Medical Eligibility Criteria for
Contraceptive Use. Geneva: World Health Organization, 1996.
- D'Arcanques C, Griffin PD, von Hertzen, et al.
Technology development and assessment. In Van Look PFA, ed. Annual
Technical Report 1997. (Geneva: World Health Organization,
1998)79.
- Chi I-c, Farr G. The non-contraceptive effects of
the levonorgestrel-releasing intrauterine device. Adv Contracept 1994;10(4):271-85.
- Faśndes A, Alvarez F, Dķaz J. A Latin American
experience with levonorgestrel IUD. Ann Med 1993;25(2):149-53.
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Use in
Hormone Replacement Therapy |
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The intrauterine system (IUS) can be used to supplement
estrogen replacement therapy (ERT), in which estrogen is used to
relieve such menopausal symptoms as hot flashes, sweating, sleep
disturbances and vaginal dryness. ERT also helps prevent
osteoporosis and cardiovascular disease.
However, ERT also stimulates the endometrium. Adding a
progestin at menopause, such as the levonorgestrel in the IUS,
counteracts endometrial stimulation and helps protect against
overgrowth of endometrial tissue, precancerous endometrial changes
and endometrial cancer.1
The sustained release of low-dose levonorgestrel directly into
the uterus via the IUS may result in more endometrial protection,
less irregular bleeding, and fewer systemic side effects than the
release of progestins via pills or implants.2
Dr. Helen Roberts, 48, senior lecturer in women's health at the
School of Medicine, University of Auckland, New Zealand, uses an
IUS as a contraceptive and as an addition to ERT. "About four
years ago I began to get night sweats," a common menopausal
symptom, she says. "I started using oral estrogen every day
and oral progestogen for half of each month. The night sweats
disappeared after about a week, but when I was taking the
progestogen pills, I felt bloated and moody.
"At that stage, the IUS began to look like a good option.
... Most of the hormone in the IUS stays inside the uterus and
only a small dose is in the systemic circulation -- about
one-third of the dose of the progestogen-only pill. This meant
that my side effects really improved. I had spotting and some
bloating for the first few months, but now -- a year later -- I
have no periods at all and no progestogen-related side effects. In
terms of contraception and hormone replacement, it has been the
perfect solution for me."
-- Kim Best
References
- Wollter-Svensson LO, Stadberg E, Andersson
K, et al. Intrauterine administration of levonorgestrel 5 and
10 microg/24 hours in perimenopausal hormone replacement
therapy, a randomized clinical study during one year. Acta
Obstet Gynecol Scand 1997;76(5):449-54;Taddei GL, Bargelli G,
Scarselli B, et al. Precancerous lesions of the endometrium
and medical treatment. Eur J Contracept Reprod Health Care
1997;2(4):239-41.
- Suhonen SP, Holmström T, Allonen HO, et al.
Intrauterine and subdermal progestin administration in
postmenopausal hormone replacement therapy. Fertil Steril
1995;63(2):336-42; Suhonen SP, Allonen HO, Lähteenmäki P.
Sustained-release estradiol implants and a
levonorgestrel-releasing intrauterine device in hormone
replacement therapy. Am J Obstet Gynecol 1995;172(2 Pt
1):562-67.
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Hormonal
Device Available in Some Countries |
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The levonorgestrel intrauterine device (IUS) is expected to be
submitted soon to the U.S. Food and Drug Administration (FDA) to
be considered for use in the United States, a process that
typically takes about a year. If approved, the device would be
eligible for distribution to developing countries through the
United States' foreign aid program.
The device has recently been approved for marketing in China
and Brazil, and is currently used by 1 million women in more than
a dozen countries, according to the manufacturer, Schering AG of
Germany. It is available in most European countries including
Russia, and in Singapore, New Zealand and several French overseas
territories, such as Martinique, Guadeloupe, New Caledonia and
Guyana. It is marketed under the brand name Mirena, except in
Nordic countries, where the brand name is Levonova.
Its price for use by foreign aid programs, however, will
determine its availability in developing countries. Some observers
believe its use in developing countries would be limited even if
foreign assistance programs can negotiate an acceptable price,
since it could still be relatively expensive compared with other
options.
"It is likely that international development agencies in
European countries such as Sweden, Germany or Finland will make
the first purchases of the device for distribution in the
developing world," says Dr. Elof Johansson, biomedical
research director of the Population Council, which owns rights to
the device. "In large part, this is because they will have
had longer experience [than the United States] using the device in
their own countries. And, in Europe, its popularity has been
strong and stable."
The U.S. Agency for International Development (USAID) would
need to negotiate an acceptable low price from the device's
manufacturer before the IUS could be considered for USAID
distribution, says Jeff Spieler, chief of research at USAID's
Center for Population, Health and Nutrition.
The IUS is expensive on the retail market, from approximately
U.S. $120 to U.S. $220, depending on the country involved.
However, lower prices have been negotiated for other expensive
contraceptives for use in foreign aid programs. For example, the
Copper T 380A IUD has a retail cost of U.S. $350 in the United
States, yet USAID pays only about U.S. $1.45. The Norplant
subdermal implant has a retail cost of U.S. $393 in the United
States, but costs USAID about U.S. $24.
-- Kim Best
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For more information, visit Family Health International's Website at www.fhi.org
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