It’s a trend that’s worrying the medical community — for the third straight year, life expectancy in the United States has remained about the same after decades of rising steadily.

New government statistics posted this week indicate that children born in the United States live an average of 78.8 years, which breaks down to 81.2 years for women and 76.4 years for men, according to a Yahoo News report, which is based on findings by the Centers for Disease Control and Prevention.

There was also a drop in the infant mortality rate, which now sits at 5.8 deaths per 1,000 birthdays for children less than 1 years of age.

The last time life expectancy has been stagnant for three years was the 1980s. For the most part, the increase in mankind’s life expectancy has been constant since World War II thanks to medical advances and better nutrition, as well as a decline in smoking.

So why is it all the sudden plateauing? Scientists aren’t really sure, but it could be due to a sharp increase in suicides and deaths from drug use. Also, there may be growing mortality in middle-aged white Americans due to alcohol, drug use, and suicides. Obesity could also be a growing mortality factor, although there is not yet any hard evidence for this.

The United States is actually nowhere near the top when it comes to longevity. Japan and Iceland are tops in that regard at 83 years of average life expectancy, following by France, Sweden, and Canada at 82 and 81 years.

Cardiovascular disease remains the No. 1 cause of U.S. mortality, followed by cancer, respiratory ailments, accidental injuries, strokes, Alzheimer’s, diabetes, influenza, pneumonia, kidney disease, and suicide, according to the report.