>>26886829In order: Bianca, Serena, Dawn, Kris, everyone else, Shauna and Iris.
All the girls 'cept the first three are two adventurous/young/immature/irresponsible to be a mother, though their Pokemon training would give them experience with providing for weaker beings, I suppose.
Bianca might be a bit of a ditz, but she would devote her life to a child. Serena's collected enough to not freak out over any hypothetical child, and Dawn and Kris have work experience and basically no personality beyond collectedness.
Shauna and Iris are dead last because they're incredibly irresponsible. Though they'd adore a cute baby, all that love'd go away as soon as the child stops being cute.