Among the different possible methods of contraception, women can use the contraceptive implant, a small stick of a few centimeters inserted just under the skin, at the level of the arm, where it will continuously release a micro-progestogen. Mode of operation, installation and removal, duration of effectiveness, contraindications and risks: an update on this method of contraception chosen by some 200 women each year.

The contraceptive implant is a small flexible stick 4 cm long and 2 mm in diameter. It contains 68 milligrams of an active substance, etonogestrel, a synthetic hormone close to progesterone. The stick itself is made of ethylene / vinyl acetate copolymer, a plastic material that does not present a risk of dissolution in the body. It also contains a small amount of barium sulfate, which makes it visible on x-rays.

In France, the contraceptive implant has been marketed since 1999 by a single laboratory, the MSD laboratory, under the name of Explanon.

Inserted just under the skin on the inside of the arm, the implant continuously delivers a small amount of etonogestrel into the bloodstream. This micro-progestogen prevents the onset of pregnancy by blocking ovulation and causing changes in the cervical mucus that prevent the passage of sperm to the uterus.

If correctly inserted, the contraceptive efficacy of the contraceptive implant is estimated at 99,9% according to the latest data from the HAS. Remember that no contraception is 100% effective. 

This action lasts 3 years, except in overweight women, in whom the dose of hormones may be insufficient for optimal protection for 3 years.

The contraceptive implant is intended for women:

• unable to take a combined estrogen-progestogen pill, because they have contraindications (risk of thrombosis in particular);
• wanting a method of contraception that does not require the daily intake of a pill.

Contraindications to the contraceptive implant

The contraceptive implant is contraindicated in the following cases:

• malignant tumors, known or suspected, sensitive to sex steroids;
• progressive venous thromboembolism;
• presence or history of liver tumors (benign or malignant);
• presence or history of severe liver disease until liver function parameters have returned to normal;
• undiagnosed genital bleeding;
• hypersensitivity to the active substance or to any of the excipients.

In the event of diabetes, overweight, epilepsy, tuberculosis or high blood pressure, the placement of the contraceptive implant is possible but will require closer monitoring.

The implantation is carried out by a health professional (gynecologist, midwife, doctor) accustomed to the procedure. It is quick and painless. 

The installation must take place between the 1st and the 5th day of the cycle in order to avoid pregnancy. If the implant is inserted later in the cycle, an additional contraceptive method (eg condom) should be used for 7 days after insertion. 

Procedure for inserting the contraceptive implant

The insertion is done under local anesthesia (cream, anesthetic patch and / or an injection of lidocaine). The insertion area is disinfected, anesthetized, then using an applicator, the practitioner inserts the contraceptive implant directly under the skin, on the inside of the arm (left arm for left-handed people, and vice versa). After placement, the implant must be easily palpable under the skin, both by the practitioner and his patient.

To limit the risk of bruising, a small adhesive bandage and a compression bandage are applied. The compression bandage can be removed after 24 hours, the dressing after 3 to 5 days. Despite these precautions, bruising, pain, swelling or itching, and in rare cases infection, may occur at the insertion site.

The contraceptive implant can be removed at any time, and at the latest 3 years after its insertion. 

The healthcare professional locates the implant, disinfects the area and then performs local anesthesia. He then makes a small incision just below the end of the implant, gently pushes the implant and pulls it out with forceps. The incision is then protected with a sterile adhesive bandage and a compression bandage.

After removal of the implant, it is possible to proceed immediately with the insertion of a new implant via the same incision, provided that the location is healthy or correct.

The implant can change the rules. They can disappear (1 in 5 women), become irregular, rare or on the contrary frequent or prolonged (1 in 5 women also). On the other hand, they are seldom more abundant. In some women, the implant may help reduce period pain.

Possible symptoms related to the placement of a contraceptive implant

The desirable effects frequently encountered (more than 1 in 10 women), although each woman will react differently to hormonal contraception, are:

• acne;
• headache ;
• weight gain ;
• tenderness and pain in the breasts;
• irregular bleeding;
• vaginal infection.

In the case of chloasma (yellow-brown pigmentation spots on the skin), the spots may become more pronounced with the contraceptive implant. To limit this risk, it is advisable to limit exposure to the sun. 

Finally, like any low dose hormonal contraceptive, the contraceptive implant can lead to the formation of an ovarian cyst, generally benign.

The two main risks of the contraceptive implant are:

• neurovascular lesions at the insertion site;
• migration of the implant to the inside of the arm or, more rarely, to the pulmonary artery.

An insertion that is too deep, a migration away from the pose following a shock or the repetition of certain movements or an anatomical peculiarity are various hypotheses put forward to explain these complications.

ANSM recommendations

Following various reports, the Medicines Agency (ANSM) published a press release in December 2019 calling for vigilance, then in January 2020, a letter sent to health professionals recalling these recommendations:

• the implant should be inserted and removed preferably by healthcare professionals who have received practical training in implant placement and removal techniques;
• at the time of insertion and removal, the patient’s arm must be folded, the hand under her head in order to deflect the ulnar nerve and thus reduce the risk of reaching it;
• the insertion site is modified, in favor of an area of ​​the arm generally devoid of blood vessels and major nerves;
• after placement and at each visit, the healthcare professional must palpate the implant;
• a check-up is recommended three months after implant placement to ensure that it is well tolerated and still palpable;
• the healthcare professional must show the patient how to check for the presence of the implant herself, by delicate and occasional palpation (once or twice a month);
• if the implant is no longer palpable, the patient should contact her doctor as soon as possible.