Studies have found, for example, that women who opt for breast augmentation are typically thinner, more active and more likely to use birth control pills, versus other women. They also tend to drink alcohol more often, and have higher smoking rates.
“If you don’t account for those factors, you can’t know whether there’s a true association between the implants themselves and health outcomes,” Balk said.
Some studies in the review found that breast implants were linked to a lower risk of certain health conditions, including breast cancer. But, Balk said, it’s hard to explain why that would be, and the lower risks could, again, be explained by other factors in the women’s lives.
Similarly, six studies in the review found a connection between breast implants and higher-than-average suicide risk. But none of them, Balk said, did an adequate job of accounting for other factors — including women’s psychological well-being.
“No one is suggesting that implants cause suicide,” Balk said.
Dr. Rod Rohrich, a plastic surgeon at the University of Texas Southwestern Medical Center, in Dallas, agreed.
“At this point, we’ve had study after study suggesting that implants are not associated with any disease risk, at least in the intermediate term,” said Rohrich, who wrote an editorial published with the study.
However, he added, since those studies have either not gone on long enough or have design flaws, the story is not over.
“We still need a national registry to follow patients long-term,” Rohrich said.
The FDA and the American Society of Plastic Surgeons have said they will collaborate on creating that national registry, but as yet it does not exist.
The registry should prove helpful, according to Balk — but only if it contains enough data to account for the other variables in patients’ lives.
For now, Rohrich said, women considering breast implants should fully discuss the pros and cons with their doctor, whether they’re getting silicone or saline-filled implants.
There are plenty of known risks. According to the FDA, they include breast pain, capsular contracture — a hardening of the breast tissue around the implant — and the formation of hard lumps under the skin.