I'm not necessarily "pro-abortion". It's not about being "pro-" anything.
However:
There are 7.9 billion people on this planet. We don't know where the limit is.
We're having water issues. China's north east is lacking water, the US is having water issues, many places are seeing problems with fresh water. At what point does the human population go beyond our ability or earth's ability to give us enough fresh water?
We're having agricultural land problems. We might have to stop raising animals in order to grow crops. Obviously with changing temperatures, either up or down, agricultural land changes, becomes more fertile, less fertile. With more urban areas, obviously there's less agricultural land out there. Some of the agricultural land isn't so good, Africa for instance has lots of not very good land.
Free and open access to global development data
data.worldbank.org
2018 we had about 48 billion square kilometres of agricultural land. This is slightly up from 47 million Sq. km in 1992. But the population of the world has increased from about 5 billion people to nearly 8 billion people in that time. Why hasn't agricultural land increased? Better growing technology or simply there isn't much land left?
Brazil is increasing land, at the expense of the rain forest which produces a lot of oxygen. We still need to be producing oxygen.
Also we see the need for more food, the richer the world gets, the more food it needs. China is coming into first world status.
The average world meat consumption is at about 45.3 kg a year (predicted 2030).
The average for industrialized countries is 100 kg a year.
For developing countries is's about 36 kg a year.
If we increase all those developing countries we're going to have massive land issue problems. Animals need crops. Crops need land.
What are the environmental impacts of food production? How do we reduce the impacts of agriculture on the environment?
ourworldindata.org
77% of land goes to dairy, or meat production.
82% of calorie supply comes from crops,.
So, 23% of land for 82% of calorie supply. Where as 77% of 18% of calorie supply is a massive problem if more meat is required.
The reality is we simply don't need more people. We need less people. We live longer, we need to acknowledge this and make sure people are working longer in their lives. But we're going to hit a brick wall and war is the only logical conclusion to that.