Contraception

INTRAUTERINE DEVICE (IUD)

Nova-T       Mirena

Description

An intrauterine device is a small T-shaped piece of plastic that is inserted into the uterus by a doctor, to prevent pregnancy. In Canada, there are two types of IUDs, Nova-T and Mirena. In the case of the Nova-T, the vertical part is coated with copper and it is often called a copper IUD. As for the Mirena, the vertical part is covered by a small tube that contains progestin (a hormone) that is slowly released into the uterus.

Mechanism of action

Nova-T

Copper on the Nova-T destroys spermatozoids in the uterus. Copper also modifies the endometrium (inner lining of the uterus) making it impossible for a fertilized egg to attach itself, if it ever happened.

Mirena

Progestin released by the Mirena thickens the cervix mucus to prevent spermatozoids from penetrating the uterus. Progestin also thins the lining of the uterus, thereby preventing a fertilized egg to attach itself, if it ever happened.

Effectiveness of action

It is a very effective birth control method. The two IUDs can be left in the uterus for five years. Nova-T provides a protection rate of 98.6%, whereas the Mirena is almost as effective as sterilization, with a rate of 99.8%.

Cost

Prices for Nova-T may vary from one clinic to another, starting at $150 or more. You can get Nova-T from pharmacies or from your doctor. It is not reimbursed by the Quebec Prescription Drug Insurance Plan and very few private companies provide refunds. The Mirena is more expensive: it costs between $330 and $350. You will need a prescription to purchase it from a pharmacy. Since July 1st 2001, it is reimbursed by the Prescription Drug Insurance Plan and by private insurance companies.

Indication

Any woman who is looking for an effective birth control method can use an IUD. She would ideally have a stable relationship, which decreases her risk of contracting a sexually transmitted disease.  

Contraindications

• Absolute contraindications to an IUD are:
• pelvic inflammatory disease (fallopian tube infection)
• possible pregnancy
• allergy to copper or another component of the IUD
• unexplained vaginal bleeding
• uterus too small
• uterine malformation

Other conditions may limit the use of an IUD. Your doctor will discuss those with you.

Insertion

The IUD is usually put in place during menstruation in order to ensure the woman is not pregnant. If a woman already uses an effective birth control method, the IUD can be inserted at any time.

It can be inserted immediately after a miscarriage or an abortion. However, many doctors prefer waiting two or three weeks. It can be inserted four weeks after giving birth.

Before using an IUD, a woman must go for a pap test and cultures for STD detection and receive the results, even if she is in a stable relationship. It is recommended that the partner also undergo screening tests for STDs. Insertion of the IUD is done under local anaesthesia of the cervix. This is not painful but it does cause cramps similar to menstrual cramps that may persist for a few minutes after insertion. These cramps can be eased by anti-inflammatory medication taken one hour before insertion.

Side effects

Nova-T

The copper IUD usually extends menstruation by one or two days.
During the first three months, bleeding becomes heavier but this usually decreases afterwards. The IUD may also increase menstrual cramps. Your doctor can prescribe anti-inflammatory medication that will reduce cramps as well as bleeding. Furthermore, some women may experience bleeding between cycles that tends to disappear with time. Finally, any unusual bleeding or abdominal pain requires a check-up with your doctor.

With the Mirena, a woman may experience irregular bleeding during the first three or four months.

After that time, periods usually become regular but they are also much lighter. A percentage of women will have no periods after one year. This is very beneficial for women who have heavy, long and painful periods. Because of the progestin, some women may at first experience headaches, breast tenderness and nausea (rarely). These side effects are not dangerous and they disappear in the first months of use.

Complications

• Pelvic inflammatory disease
  The IUD does not increase the risk of pelvic inflammatory disease (salpingitis or infection of fallopian tubes) after the first month of use. When it occurs, this infection is associated with sexually transmitted diseases rather than the IUD. The Mirena provides some protection against infection of the fallopian tubes.
   
• Ectopic pregnancy
  The prevalence of ectopic pregnancy (pregnancy in the fallopian tubes) is very rare for women who use an IUD. However, if a woman does become pregnant, she must immediately consult with her doctor.

Removal

The IUD is removed during menstruation. However, removal may be done at any time during the cycle if there was no unprotected sexual intercourse since the last menstruation or if a woman wishes to become pregnant.

How to choose

The choice you make depends on your needs and your gynaecological history. All women can use the Mirena, particularly those who have heavy, long and painful periods. However, a woman who has a regular cycle that is not painful or overly abundant will be very satisfied with the Nova-T. Talk with your doctor as he will provide you with good advice.

Emergency IUD

A copper IUD can be inserted within seven days following unprotected sexual intercourse. This would prevent pregnancy in almost all cases. It must be considered, especially if the delay for post-coitus birth control (morning-after pill) has expired. The Mirena is not effective as an emergency IUD contraceptive.

The above was translated from an excellent text produced by the family planning team at the Centre hospitalier rŽgional de Rimouski.
http://www.planningchrr.com/