My guppy has been pregnant for about a month and a half now. She's not extremely big, but since it had been a while, i figured she was due soon. She's been in a breeder box for about two weeks now. Yesterday I was changing some of the water, and it kinda scared her and my pregnant molly. She managed to escape so when i was done I returned her to the box. She later gave birth to an egg, a couple babies that seemed to not be fully developed and about 4 healthy looking babies that died. She still looks pregnant and has her gravid spot. Is it possible that the stress just made her have a premature birth to some of the babies? If so, are there still more developing inside of her, or is she done with this pregnancy? Please let me know.

Try not to change water before and after she gave birth. You can took her out once she completely delivered the babies and leave the babies inside the breeding box.

Put some frogbits or floating plants. It will help not to scare the babies n the mother.

Well, maybe that. or possibly a fry or frys are blocking the birth canal. Well you can expect plenty babies from that molly.