Embryo Tales

Learning About Embryology

Embryology starts with the study of embryos and their development. It also includes all aspects of reproduction and related health as well. Scientists are still learning new things about reproduction and development every day. Embryo Tales are stories about this broad area of science.

Embryo Tales are based on articles that are a part of the Embryo Project, which is an encyclopedia on all things embryology and reproduction. In these Embryo Tales, you may find stories on tissue development, menstruation, sex chromosomes, what it means to be intersex, the history of reproductive biology, and much, much more.

If you want to take a step further and learn more about any of these subjects, look on each story page for the links to the Embryo Project articles on which they were based.

Special thanks to Arizona State University's Center for Biology and Society and to the editors who have helped create these stories: Dina Ziganshina, Risa Schnebly, Emily Santora, and Dr. Biology.

Someone raising their arm to show off armpit hair

Helpful Sex Hormones

Written by: Risa Aria Schnebly

Our biological sex is mainly controlled by our sex chromosomes. But sex hormones also influence what body parts and characteristics we have.

An ultrasound showing a blurry image of a fetus.

How Fast Do Embryos Grow?

Written by: Megha Pillai, Logan Hunt

We start off as a single tiny cell, and yet somehow we are born as whole humans. Get to know the stages of that process and how quickly we develop.

An intersex pride flag, showing a purple circle on a yellow background

Intersex: More than Male and Female

Written by: Risa Schnebly, Riley McInnis

You might think that people can be born only as either males or females. In fact, lots of people are born with a blend of male and female traits. We call this being “intersex,” and it happens more often than you may think.

A small T shaped piece of plastic resting in an open palm

Introducing the IUD

Written by: Molly Jacobson

Doctors place Intrauterine Devices (IUD) in the bodies of some females to help prevent pregnancy. Learn about how these devices work and how long they’ve been around.

Menstruation Matters

Written by: Emily Santora

Periods are a natural, normal part of life, and many people around the world experience them. So let’s talk about why and how they happen.

A woman clutching her abdomen, experiencing period cramps.

Periods: What Should You Expect?

Written by: Emily Santora

Sometimes things don’t work as you expect them to, including periods. Learn more about what causes some girls to have irregular or painful periods.

Plan B One-Step Emergency Contraception packaging

Preventing Pregnancy with Plan B

Written by: Molly Jacobson

Is there any way to prevent pregnancy after sexual intercourse? Learn about Plan B, an emergency contraceptive.

Shedding Light on Endometriosis

Written by: Emily Santora

A lot of illnesses, like colds, have very visible symptoms, but other conditions are not so obvious. Learn about how people spot and treat a condition called endometriosis.

A side view illustration of the internal female reproductive system

Summarizing Sex Traits

Written by: Risa Aria Schnebly

Our biological sex affects the way we look in some obvious ways, like deciding what body parts we are born with. But, it also has effects on a range of other sexual traits that you might not expect.

An image of ovaries in a person with PCOS. The image features an external look at a bumpy ovary attached to the rest of the female reproductive system, as well as a close-up, detailed look at the cysts within the ovary.

The Mysterious Case of the Missing Periods

Written by: Emily Santora

Estrogen and testosterone are two hormones that cause puberty. But what happens when the body doesn’t produce the amounts of hormones that it usually does?

Embryo Tales are created from encyclopedia articles that are a part of the Embryo Project.

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Embryo Tales

Learning About Embryology

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