Radical idea: treat mothers as professionals. Train them, certify them, give them resources and support networks, then pay them to raise kids until school age or even beyond. It is a full time job, and should be treated as such if governments want to incentivise childbirth.
Why just mothers?
I didn't want any child, but clearly stated that I would support any choice she made, and any children we would have would have my love and support. I don't bear any social pressure to have kids, I don't get pregnant, i don't feel any kind of desire to have children (I used to be a youth camp counselor, my ego about being a role model was well filled by the time I was 25).
Anyway, since the choice is primarily on the mother (as it should be), it stands within reason that the formation and remuneration are given to them in priority.