Here's a look at some of the top health news being talked about around the U.S. and the world today:

• New guidelines could allow more women who have previously given birth via a C-section to attempt to give birth vaginally, it was announced Wednesday. Reported in the Chicago Sun Times, the change in the American College of Obstetricians and Gynecologists comes amid concerns that too many women are giving birth via surgery because many hospitals fear the liability that trying a traditional birth would bring.

• Many common knee ligament injuries heal just as well with physical therapy as with surgery, Reuters reported. Most people who have a common knee ligament injury fare just as well with intense physical therapy as they do with surgery, according to a study comparing the two techniques released on Wednesday.

• There could be hope for relief for sufferers of celiac disease, a painful gut disorder that makes people unable to tolerate gluten, the protein found in wheat, barley and rye, it was reported U.S. News and World Report. Scientists have found molecular triggers of the disease, which could eventually lead to drug relief for those who suffer from the disorder, it was reported.

To get information about a local environment event or announcement mentioned in the Tuesday environment briefs, contact reporter Tina Reed at tinareed@annarbor.com, call her at 734-623-2535 or find her on Twitter @TreedinAA.