A few weeks ago, as we sat on a bus that would take us down to my nephew’s second birthday party, I turned to my fiancé and said, “What if I got my tubes tied?"

“What?!” he whispered. He was more alarmed than I expected — given the fact that I have been making noises about my disinterest in having children almost since we first started dating two years ago.

“What if you change your mind?” he almost pleaded. "I don’t want you to live with regret."

I wondered if he was right. I’ve been told by the women in my family that my baby-making instincts could kick in at any moment. My mother tells me that at 27 she switched from never wanting children, to really, really wanting a baby. I’m 28 now — perhaps there is still time for me.

But the more I’ve thought about it, the more I think this isn’t true. That's because many of my main reasons for not having children aren't an aversion to kids per se — but because I care deeply about the planet:

1. All of our environmental problems could be mitigated if there were fewer people on this planet.

I really take issue with the assertion that the child-free are selfish. When I look at the most alarming environmental problems, they all boil down to the sheer number of people on the planet — consuming, destroying, wasting, poisoning.

When I go hiking and the trail is clogged with tourists trampling flora and using their iPads to take pictures of the waterfall, I shake my head and think, we need fewer people. When I see satellite images of grids of slums, or factory farms, or suburbs, I think, we need fewer people.

When I see what are supposed to be helpful statistics — “If everyone in the United States flushed the toilet just one less time per day, we could save a lake full of water about a mile long, a mile wide, and four feet deep every day!” — I want to shake the author’s shoulders and tell them, “Forget letting it mellow; we just need fewer people!"

People tell me, “But you’re the kind of person who should have a baby!” I see their reasoning. It’s within the realm of possibility that I could have a child with a net positive effect on the environment. Perhaps she will lead an effort to prevent another oil refinery from opening, or invent a more efficient way to store energy created through solar and wind power.