Lesson 12
Where Do Babies Come From?
Key Ideas
- To make a baby, a sperm and an egg need to meet and join together.
- The egg comes from an ovary and the sperm comes from a testicle.
- When the egg and sperm join, the result is called a zygote, which grows in a uterus.
- Pregnancy usually takes about nine months.
- Sometimes a doctor helps sperm and egg meet outside the body in a process called IVF.
- Sometimes a donor provides sperm or an egg to help a family have a baby.
- A surrogate is a person who grows a baby in their uterus for someone else.
- Transgender men and non-binary people with uteruses can become pregnant too.
- Families are made in many different ways and all of them are real.
| Term | Definition |
| Sperm | Tiny cells made in the testicles that can join with an egg to make a baby. |
| Egg (ovum) | A cell made in the ovaries that can join with sperm to make a baby. |
| Fertilization | When a sperm and an egg join together. |
| Zygote | The first group of cells that forms when a sperm and egg join. |
| Pregnancy | When a fertilized egg grows inside a uterus into a baby. |
| IVF (in vitro fertilization) | When a doctor joins a sperm and egg outside the body, then places them in a uterus. |
| Donor | A person who gives their sperm or egg to help someone else have a baby. |
| Surrogate | A person who carries a pregnancy in their uterus for another person or family. |