Do you mean pins are high until you initialize DDRx registers, or do you mean pins are driven high from the moment you write tto DDRx until the moment you write initial pins values to PORTx or PTx registers?
1) In the first case peraphs your circuit lacks pull down resisotrs.
2) Each output capable port pin must have some latch. To initialize these latches you should write initial pin states pattern to PORTx / PTx register before switching pin direction(s) to output(s).
PORTA &= ~1;
DDRA |= 1;
