Implanon is a matchstick-sized contraceptive implant that works by slowly releasing a synthetic hormone called etonogestrel, a synthetic version of the female reproductive hormone progestin. Though all progestin-containing contraceptives slightly increase a woman’s risk of a blood clot, Implanon may increase a woman’s risk by 40%. Implanon blood clots may cause deep vein thrombosis (DVT), pulmonary embolism, heart attack, stroke, permanent disability, organ damage, organ failure, or death.
Implanon is a matchstick-sized rod that is implanted under the skin of the upper arm to protect against pregnancy. It works by slowly releasing etonogestrel (a synthetic version of the hormone progestin) into the body. The progestin inhibits ovulation (when the ovaries release an egg) and thickens the cervical mucous. Fewer than 1 per 100 women who use Implanon to prevent pregnancy will become pregnant.
Since Implanon was first sold internationally in 1998, around 2.5 million women have used Implanon. The product is sold by the company Organon International. It was approved by the U.S. Food and Drug Administration (FDA) in 2006. The newer version of Implanon is Nexplanon.
Studies of Implanon Health Risks
May 2012 — A study published in the British Medical Journal has found that women who use many types of non-oral hormonal contraception have a higher risk of blood clots. The researchers found that women who use subcutaneous contraceptives (such as Implanon) have a 40% increased risk of developing a blood clot compared to women who did not use hormonal contraceptives.
The researchers analyzed data from Danish, non-pregnant women, with no history of venous disease or cancer, between the ages of 15-49, between the years 2001 to 2010. They found that all non-oral hormonal contraceptives were associated with an increased risk of venous thrombolic events, except for women who had intrauterine implants (IUDs).
Implanon Blood Clots
All progestin-containing contraceptives slightly increase a woman’s risk of developing a blood clot. Implanon contains etonogestrel, a synthetic version of progestin. Some studies have found that Implanon blood clots are twice as likely to occur compared to women who use other types of synthetic progestin (such as levonorgestrel).
Implanon blood clots are a severe, life-threatening side effect of this contraceptive. They are most likely to form in deep veins in the legs, in a condition called deep vein thrombosis (DVT). If the blood clot remains in the legs, it may cause severe damage to the veins. If parts of the blood clot break loose, they may travel to the heart and be pumped into the lungs, causing a pulmonary embolism. If the blood clots form in an artery, they may travel to the heart (causing a heart attack) or the brain (causing a ischemic stroke). They may also travel to other parts of the body and cause severe damage, including the eyes.
Implanon blood clots can cause severe pain and suffering, permanent disability, organ damage, organ failure, or death.
Implanon Side Effects
The most serious side effect of Implanon is death or permanent disability, which may be caused by a blood clot that becomes trapped in a major internal organ (such as the heart, brain, or lungs). All women have a risk of developing these serious side effects, but women with certain risk factors are most likely. These risk factors include smoking, being over 35 years old, or have a history of blood clots or cardiovascular disorders.
Serious side effects of Implanon include, but are not limited to:
- Blood clots
- Irregular menstrual bleeding
- Weight gain
- Abdominal pain
- Depression, moodiness
- Decreased sex drive
- Mild insulin resistance
- Sore breasts
- Pseudotumor Cerebri (PTC)
- Idiopathic Intracranial Hypertension (IIH)