In most cases (to my knowledge at least), when eggs from oviparous reptiles are removed from uterus, even just hours prior or after normal time of egg-laying (in case of dystocia for example), they fail to develop. My last experience is eggs of Liasis papuanus: half of the clutch was laid by the female, placed in incubator and hatched successfully; due to egg-binding the other half had to be removed by surgery. Placed in the same conditions they all began to rot in a few days, although they were fecunded and presented an embryo. Is ther a chemical signal (hormonal?), or even a mechanical signal due to the physical stress of an egg-laying that trigger development outside uterus?

(Please forgive me for my broken English).