It's my understanding the world population growth as actually slowed down especially in the industrialized nations. In fact this is one of the reasons many in U.S. congress want to change the social security program for seniors.
Our Social Security program was based on younger generations paying enough taxes into the program so that when the older generation retired from work at age 62 or older the seniors would receive a monthly check for the remainder of their lives.
After the "baby boomers" each generation has produced less children for a variety of reasons: Better birth control methods, couples opting to have fewer children, more women deciding to make careers a top priority, legalized abortions, and more men having vasectomies...etc
"(CNN) — The US fertility rate fell to the lowest point since record keeping started more than a century ago, according to statistics released by the Centers for Disease Control and Prevention." - August 11, 2016 CNN
The US fertility rate has been in a steady decline since the post-World War II baby boom. Back at its height in 1957, the fertility rate was 122.9 births per 1,000 women
In the first three months of 2016, the fertility rate in the US fell to the lowest level. The rate was 59.8 births per 1,000 women.
Europe has also seen steady decline in birth rates.
"Across Europe birth rates are tumbling. The net effect is a ‘perfect demographic storm’ that will imperil economic growth across the continent." - The Guardian Aug 22, 2015
"Globally the Total Fertility Rate has dropped from 4.45 in 1970 to around 2.5 in 2014. If the rate keeps falling, the world population will eventually stop growing and may actually start shrinking towards the end of the 21st century."
Having said that counties like India and China contain almost 1/3rd the world's population.
Needless to say not many sources are proclaiming (earth) in general is overpopulated these days.
It's just overcrowded in (certain pockets) of the world.