Surgeons at The Johns Hopkins Hospital in Baltimore last month successfully removed a donor's healthy kidney through her vagina instead of through an incision in her abdomen. This is not the first time kidneys have been pulled from the body this way, but it is the first time such a procedure has been performed to remove a healthy organ.

The kidney was removed from Kimberly Johnson, 48, of Lexington Park, Md., who donated it to her ailing 23-year-old niece, according to the Associated Press. Johnson is among the first patients in the world to receive "natural orifice transluminal endoscopic surgery (NOTES)," a new procedure in which doctors remove organs and tissues through the body's natural openings—the mouth, the anus and the vagina—instead of via ones created in the skin by a surgeon's scalpel.

Mohamad Allaf, the urologist who performed the three-hour operation, says it went off without a hitch. Within minutes of extracting the kidney on January 29, another team of surgeons began the two-hour operation to transplant it into the recipient. Johnson was up and walking the same day—and released from the hospital the following morning. Allaf says she is "back to normal activity" and that the only restriction was a two-week ban on heavy lifting. (FYI: Her niece spent a few days in the hospital, which is typical after receiving a kidney transplant,  and is also doing well, according to Allaf.) "It was easier than childbirth," Johnson, a mother of three, told the AP.

Does NOTES sound too good to be true? And if not, why isn't it used more often to spare patients the knife? We asked Wahid Wassef, a gastroenterologist at the University of Massachusetts Medical School in Worcester who has done extensive research on the procedure, to explain its pros and cons.

[An edited transcript of the interview follows.]

What is the advantage of removing an organ through the vagina, mouth or anus?
If you go through an orifice as opposed to an incision in the skin, the patient will have no scars. And the immune system appears to emerge stronger after these procedures compared to standard surgeries, which could result in fewer infections and faster healing. With no incision in the abdomen, you also eliminate the risk of hernias, which occur when part of the intestine pushes through the abdominal muscle. Let's say somebody has a gallbladder taken out the old-fashioned way; if it happens that one of the stitches in the abdominal muscle gives way, you have a weakness, and part of the intestine can push through that area forming a bulge under the skin. This is not an issue when no incisions are made in the abdomen.

How long have doctors been doing surgeries like this?

This procedure started about six years ago in humans; it had previously been done in animals.

How many times has the procedure been performed?
At least 15 procedures have been performed worldwide in addition to this one: this includes appendectomies (appendix removals) and cholecystectomies (gallbladder extractions) through the mouth and vagina.

How are kidneys usually removed?
Over the past 10 years or so, this has been done laparoscopically, which is a way of performing surgery using small openings. Doctors make two or three small incisions, each about a half inch, or the length of a staple, on the abdomen—usually one in the bellybutton, one a few inches above the bellybutton, and another a few inches to the side of the bellybutton. Through these incisions, they insert rigid plastic tubes or "ports," which are used to guide surgical instruments and scopes, or cameras, into the body. The scope allows you to visualize what you are doing; you have television monitors in the operating room that magnify images from inside the body by 10 or 20 times. A larger incision about six inches (15 centimeters) long is then made several inches below the belly button, and this is where the kidney is pulled out.

How is the new NOTES procedure done?
You make a six-inch incision in the back of the vaginal wall and insert one flexible tube that contains four channels through which you insert surgical instruments and cameras. Then you dissect upwards toward the kidney, which is located midway up the back. Dissecting means you are using scissors to open up layers of tissue, called fascial planes, to get to the kidney. Separating these layers of tissue feels like peeling away layers of cotton candy. Once you get to the kidney, you identify blood vessels supplying it with blood, put clips on the vessels so they don't bleed, and cut them free from the kidney. (The clips are actually left in the body after the surgery.) To remove the organ, doctors might use the "Roth Net" retrieval net, which is like a collapsible butterfly net. You thread the Roth Net through the tube, which opens up on the other side and "catches" the kidney like a net capturing a butterfly. Then kidney is pulled through the vaginal incision.

[Instead of using the Roth Net, the Hopkins team actually used a sterile plastic bag to extract the kidney, according to Allaf. The bag is similar to the Roth Net in that it slides through a narrow tube, opens at the end and captures the kidney.]

Is this procedure safer than traditional surgery?
With any surgery there are always certain risks, such as infection or excessive bleeding. It's not yet clear whether the risks are lower for NOTES. There are no clinical trials that I know of comparing this technology with any other.

Is the recovery time shorter?

Yes. With laparoscopy the recovery time is about one to two days. With these NOTES procedures it could potentially become an overnight procedure (meaning you have the surgery one day, and go home the next).

Why does it take longer and require reconstructive surgery for women to recover from hysterectomies (removal of the uterus and sometimes the ovaries and fallopian tubes through the vagina) than from this procedure?
Part of the uterus is connected to the vaginal wall. The uterus actually anchors the vaginal wall, which in turn anchors the bladder and rectum. So when you pull out the uterus, you are ripping the vaginal wall. One the other hand, when you pull out the kidney, you're not removing any architectural support of the vaginal wall, bladder and rectum.

What are some of the drawbacks of NOTES?

If we're not careful and don't close things as well as we ought to, infection and bleeding could become an issue. We don't have excellent tools or a lot of experience yet on closing some of these incisions.

Is this procedure more expensive and time-consuming than standard surgery?
The answer to both of those questions is: yes—right now. But once you have the right tools, it's not going to be. As more doctors become familiar with this procedure and they have more precise tools, it will ultimately be less expensive than it is now.

In 10 years, do you expect that this procedure will become the norm?
I think it's going to be the next wave. The majority of organ removals will probably occur through orifices.