No just no, if there was any way to essentially have designer breasts it would become a fashion.
Thats different as thats adults (well was) if there was a pill a developing child could take that would dictate the growth of theirs, thats a totally different bucket of fish and getting close to designer baby territory
Binding and breast ironing aside I think it would be nice if there was a way to stop breasts from growing without causing harm to girls... At least from growing too much as very big breasts can be very inconvenient as many big breasted women on Ovarit themselves have said plus they can cause back pain...
I dunno why human evolution did this to us when most other mammalian females do not have these problems of having their mammaries out unless they are feeding their babies...