How many babys do the boa constructers have?

by constructers I'm hoping you mean constrictors, and a large constrictor can have 30-40 living young averaging about 15-20 inches (38-51 cm) in length, smaller constrictors can rage from 8 -13 living young and before anyone thinks about breeding their boa they should know all about egg bound and know that they risk the babies and the parents' life!