Alighting on the buds of our Marsh Milkweed plants, you can see in these photos that the female Monarch is curling her abdomen to the underside to deposit eggs. She will go from bud to bud and leaf to leaf ovipositing one egg at a time. A female, on average, deposits 700 eggs during her lifetime, fewer in hot, dry weather.
Butterflies do not “lay” eggs; we say oviposit or deposit. And you wouldn’t describe a caterpillar as hatched, but that it has emerged or eclosed.
In the above photo you can see how she is contorting her abdomen to correctly position the eggs.