Archive · 26 Aug 2026
Some Animals Can Pause Pregnancy Through Embryonic Diapause
Some animals have a special way to pause a pregnancy.
This process is called embryonic diapause.
The fertilized egg does not immediately attach inside the uterus.
Instead, its development waits for better conditions.
More food or a safer environment can help the young animal survive.
Female kangaroos may use this pause while caring for a joey.
They may also pause development when food is scarce.
The kangaroo embryo starts growing again when the pouch is available and enough milk and food can support a new baby.
Embryonic diapause lets some animals delay embryo implantation and development.
The pause can continue until conditions such as food abundance or safety improve.
Female kangaroos may pause embryo growth while nursing a joey.
Food scarcity can also trigger a pause in kangaroo embryo development.
Kangaroo development resumes when the pouch is free and resources improve.
- Who
- Some animals, including female kangaroos.
- What
- They can temporarily pause embryo implantation and development through embryonic diapause.
- When
- Until conditions such as food availability, safety, nursing demands, and pouch availability become favorable.
- Where
- In the uterus; for kangaroos, the developing young later uses the mother’s pouch.
- Why
- To time birth for conditions that provide sufficient milk, food, and protection.
- Biological process
- Embryonic diapause
- Definition
- A temporary pause before a fertilized egg implants and continues developing.
- Example identified
- Kangaroos
- Possible trigger
- Nursing an existing joey
- Another trigger
- Food scarcity
- Resumption conditions
- A free pouch and improved resources
- Reproductive benefit
- The young arrives when the mother can provide a full milk supply.