Well-known birth control pills such as Yaz and Yasmin need stronger warnings about the risk of blood clots, an FDA advisory committee recently recommended, according to news reports. This comes after the agency itself recently released an analysis showing the drugs pose a greater risk of clots compared to older birth control pills, while acknowledging other studies have not found an increased risk. With all the controversy, where does this leave women who take Yaz and related oral contraceptives?
Most birth control pills combine two types of female hormones: estrogen and a progestin. Newer pills pair estrogen with the progestin drospirenone, a synthetic hormone that may minimize side effects such as fluid retention, breast tenderness, weight gain and increased blood pressure. Other drospirenone-containing pills include generic Gianvi, Loryna, Ocella, Syeda, Zarah, and Beyaz and Safyral. Some are also approved to treat moderate acne and premenstrual dysphoric disorder.
Use of any combination birth control pill increases the risk that a blood clot will form in a deep vein of the leg. But overall, that risk is relatively very small: between 9 and 10 women in 10,000 per year, compared to about 0.5 to 3 women in 10,000 per year who do not take any birth control pills. If the clot breaks off, travels to the lungs and blocks blood flow, it can be deadly. These conditions considered types of venous thromboembolism (VTE).
Some studies have linked certain progestins used in birth control pills to a higher risk of VTE compared with an older progestin, levonorgestrel.
But many of these studies had problems, according to both the FDA and an analysis of the evidence conducted for Consumer Reports by the American Society of Health-System Pharmacists. Most studies did not consider all risk factors the subjects may have had for VTE, so researchers couldn't accurately gauge the risk from oral contraceptives alone. Some studies failed to identify the types of pills used in the comparison group or confirm diagnoses of VTE. And many had a small number of cases of VTE, making it difficult to assess differences in risk.
The FDA's recent review of the medical histories of more than 800,000 women reported a 1.7-fold increased risk of blood clots in those who took pills containing drospirenone compared with those on older combined oral contraceptives. Another way of saying that is about 10 out of every 10,000 women who take birth control pills containing drospirenone will experience VTE in a year, compared with 6 in 10,000 who use other hormonal contraceptives.
Two studies from 2009 found a 1.5- to 2-fold higher risk of VTE in users of drospirenone compared with users of levonorgestrel, and two 2011 studies reported a 2- to 3-fold greater risk.
A subsequent 2011 study, published in the British Medical Journal, concluded that women who took birth control pills containing drospirenone and certain other progestins had at least twice the risk of VTE compared with those who took pills containing levonorgestrel. It also examined the risk of VTE in users of pills combining drospirenone with a smaller dose of estrogen; the risk was not reduced. In another 2011 study, published in the Canadian Medical Association Journal, drospirenone-containing pills were associated with a higher risk of VTE compared with both newer and older pills.
Conversely, three other studies showed no difference in the risk of VTE between drospirenone-containing pills and pills containing levonorgestrel or other progestins.
Given this conflicting evidence, two FDA advisory committees in a joint meeting last Decomber voted 21 to 5 that the labeling of Yaz and similar pills should contain more information about the blood clot risk, according to news reports. However, the panels were split on the overall risk, voting 15 to 11 that the benefits of the pills in preventing unwanted pregnancies outweighed the risks of VTE.
However, the FDA does not have to follow the advice of its advisory committees but it often does.
If you think you have experienced an adverse event with this drug or any drug, especially if it is of a serious nature, it is important to 1) tell your doctor immediately and 2) report the event to the Food and Drug Administration via the FDA's MedWatch website at https://www.accessdata.fda.gov/scripts/medwatch/medwatch-online.htm or by calling 1-800-FDA-1088.
Although the absolute risk of VTE may be small and even debatable among medical professionals at this time, there are steps you can take now to reduce your exposure if you are concerned:
Talk to your doctor. If your birth control pill contains drospirenone, the FDA advises that you continue to use it unless told otherwise by your healthcare provider. If you're considering using a drospirenone-containing pill, your doctor should weigh its risks and benefits in light of your personal risk for developing blood clots. Because you may use an oral contraceptive for several decades, your doctor should reassess your risk for VTE periodically.
Address your risk factors. The risk of a blood clot with combination birth control pills is highest during the first year of use especially in the first three months and when you restart the pill after a break of four weeks or longer. But the more risk factors you have, the greater your risk, so you should quit smoking no woman should take any combination birth control pill and smoke. And try to lose excess weight. Other triggers for VTE include being obese, recent pelvic or abdominal surgery or recent trauma to or fractures of the legs that lead to relative immobility, clotting disorders, chronic heart failure, frequent, lengthy airplane or car trips, and diabetes If you're planning surgery, ask your doctor about precautions including low-dose blood-thinning drugs and compression devices to keep blood flowing in the legs.
Stay active. Regular exercise such as walking improves circulation and reduces the risk of VTE. Move your legs often if you have to sit or lie down for an extended period of time. On long airplane trips, get up and walk every hour or so; if you can't, flex your calf and thigh muscles, and raise your toes 10 to15 times each hour to prevent blood from pooling in your legs. In addition, avoid alcohol and drink plenty of fluids, as dehydration makes blood more likely to thicken and clot.
Avoid the pill immediately after childbirth. The risk of VTE escalates in pregnant and postpartum women. Don't use combined hormonal contraceptives if you think you might be pregnant or during the first 21 days after delivery. Women who don't have risk factors for VTE can generally initiate use within 21 to 42 days postpartum, but those who have risk factors including recent cesarean delivery should wait at least 42 days. Alternatives for postpartum women include progestin-only contraceptives, IUDs and condoms
Know the symptoms of VTE. Seek medical attention immediately if you have swelling, pain, warmth, redness or discoloration of one leg, swollen-looking veins in the leg, or pain or tenderness in the calf muscle or groin. Symptoms of a clot in the lung include sudden shortness of breath, sharp chest pain, coughing up blood, and less commonly, dizziness, back pain or wheezing.
Monitor your potassium level. Drospirenone may increase serum potassium levels too much and for that reason should not be used by women with kidney disease. If you're on another medication that may increase potassium, you should have a blood test to check your level during the first month of taking a drospirenone-containing pill. Tell your doctor what medications you use, especially ibuprofen, naproxen, potassium-sparing diuretics, potassium supplements, and and certain blood-pressure drugs such as angiotensin receptor blockers (ARBs) and ACE inhibitors.
Don't use any type of hormonal contraceptive if: you have a strong family history (first-degree relative) of VTE or a personal history of blood clots, heart attack, stroke or breast cancer; or if you smoke more than 15 cigarettes a day or are over age 35 and smoke. Instead, consider methods such as the diaphragm, sponge, condom, or a non-hormonal IUD.
Serious blood clots are relatively rare in young women with limited risk factors. Recent trials report an increased risk of VTE with drospirenone-containing birth control pills compared with older versions of the pill, although the results of previous studies were conflicting. All the studies had limitations.
However, as an analysis performed by the the American Society of Health-System Pharmacists for Consumer Reports points out, at this time, no study shows a reduced risk of blood clots with Yaz, Yasmine or similar drugs compared to second-generation birth control pills that contain levonorgestrel. Women considering a drospirenone-containing pill, or any combination birth control pill - should be aware that there is a small, increased risk of having a blood clot and VTE. And, that some studies indicate there is a small but greater potential risk of blood clots and VTE for pills with drospirenone. If you are concerned about this, discuss its risks and benefits with your doctor, and consider a pill or method with a more consistent safety profile. Women who use drospirenone-containing pills should be aware of the symptoms of VTE.
These materials were made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by a multistate settlement of consumer fraud claims regarding the marketing of the prescription drug Neurontin (gabapentin).