Whenever pregnant women think of childbirth, there's a bit of nervousness, I think. It's like being on a conveyor belt, headed to the unknown, even if they have been through it before. I did this study for myself when I was pregnant with my third child and it really helped strengthen my faith.

Nevertheless she will be saved in childbearing if they continue in faith, love, and holiness, with self-control. Timothy 2:15

Now, at first glance, doesn't this seem unfair?

What about women who are infertile? Or single, or widowed without kids?

Will they not be saved?

Paul wrote that being single was fine.

But I say to the unmarried and to the widows:
It is good for them if they remain even as I am...
1st Corinthians 7:8

And God is the One who decides when a child is born.

But to Hannah he would give a double portion, for he loved Hannah, although the YHWH had closed her womb. 1st Samuel 1:5

Will they not be saved?

No!

Salvation is a free gift!

It's the emphasis that is incorrect- she shall be saved through childbearing
not
she shall be saved through childbearing.

This is a promise for childbearing women to cling to in the most personal, painful times of our lives. He created our bodies, and He is there to save and sustain us through all the consequences of the Fall.
Praise the Creator!