U.S. Food and Drug Administration (FDA) experts today will review the potential risks of Bayer AG's permanent contraceptive device in light of growing complaints over possible side effects, and consider whether its use should be restricted.

About 17,000 women had the Essure device implanted and claim it has hurt them, causing chronic pain, heavy bleeding, fatigue and skin allergies, according to Reuters. The FDA panel will discuss potential changes to the product's label and whether further clinical studies should be conducted but will not formally vote on its recommendations.

Bayer obtained Essure with its $1.1 billion acquisition of Conceptus in 2013, and maintains the product is safe and effective. Roughly 750,000 Essure devices have been sold, mostly in the United States.

Patricia Carney, M.D., Bayer's medical director for Essure, said the company welcomes the discussion. "We want to understand as a company what is going on," she told Reuters. "We want to know whether there is a link to the product."

Already the complaints have led some physicians to re-examine their use of the device, a small metal spring that is inserted into the fallopian tubes. Originally approved by the FDA in 2002, Essure is a non-hormonal permanent birth control option with a non-surgical procedure. During the procedure, a doctor permanently places the soft, flexible Essure insert into each of the patient's fallopian tubes; the inserts work with a woman's body to form a natural barrier that keeps sperm from reaching the eggs, preventing pregnancy.

Sebastiaan Veersema, M.D., a gynecologist at St. Antonius Hospital Nieuwegein in the Netherlands, was an early European adopter, implanting the device in nearly 1,400 women and training dozens of practitioners in its use. But he now believes more research must be conducted to establish whether there is a relationship between the device and the problems relayed by some patients. "If there is something wrong with the device I want to know," he said.

Veersema added that a stronger screening process might be warranted to avoid implanting Essure in women who already have a uterine problem, such as fibroids.

In July, the FDA approved the use of transvaginal ultrasound (TVU) as a means of ensuring the proper placement of the Essure permanent birth control device within three months of its insertion. TVU offers an alternative to the only previous confirmation test that FDA had endorsed to examine Essure's placement: a modified hysterosalpingogram (HSG), which is an X-ray of the uterus and fallopian tubes after they have been filled with contrast dye. A physician determines whether HSG or TVU are appropriate as a confirmation test for an individual patient, but if they are unable to do so with a TVU then an HSG must be performed.

The FDA requires physicians who offer Essure to complete a comprehensive training program on the use of TVU with Essure. The program began earlier this month with the physicians who perform the procedure the most often and is expected to wrap up by mid-2016. Certification on TVU will be required of physicians to offer Essure, but they can continue to use the HSG method until they are trained for TVU.

Angela Lynch was 28 when she received the implant. She had three children and did not want any more.

"Because I had just had a kid I wrote off all my symptoms as hormonal, my body trying to adjust," she told Reuters. "After two years I started losing hair. Then I started losing teeth, and over time it got to where my whole body was hurting."

In 2012 she had the device removed and underwent a hysterectomy. "After three days it was like I woke up from a five-year flu," she said.

Cindy Basinski, M.D., who consults for Bayer and will be testifying on the company's behalf at the FDA meeting, has been implanting the device since 2006 and has conducted about 1,100 procedures with minimal complications. She has had "a couple" of patients come to her with complaints and one asked for the device to be removed.

Basinski, who practices in Newburgh, Ind., said she in "no way discounts the patients out there recounting their experience," but said it was not possible to draw scientific conclusions from anecdotal information.

For some doctors, it is not just the implantation of the device that needs to be looked at, but the way in which it is removed.

Shawn Tassone, M.D., who practices at a clinic in Austin, Texas, began implanting Essure in 2008, and said there is no standardized method for removal. "I'm hoping that all this will change the way doctors counsel their patients," he said. "Instead of saying Essure is an easy procedure with no side effects, (they should) say this is a surgery and there are people reporting complications."