When I was pregnant with my first child, nearly all the focus was on the baby. Every appointment, every conversation revolved around her growth, her size, and her due date. The placenta was mentioned briefly during my anatomy scan, but it never felt like something I needed to think much about.

It wasn’t until late in my pregnancy that curiosity set in. After reading about other women’s experiences, I asked to see my placenta after my daughter was born. My OB-GYN proudly held it up and told me it was healthy, almost as if I had accomplished something remarkable. In that moment, I realized I had grown an entire organ that supported my baby for nearly 42 weeks.

Now, more than a decade later, placentas are at the center of my work and passion. Yet I know many parents still don’t fully understand what the placenta is or how much it does during pregnancy. That’s why I want to share what this incredible organ truly is and why it matters.

What Is a Placenta?

The placenta is an organ within the uterus. Its job is to give the baby everything it needs to grow and thrive until birth. The placenta has three structures: membranes, an umbilical cord, and the main part, the placenta itself.¹

What Does the Placenta Do?

The placenta is a facilitator organ, not a filter, as it’s often misunderstood. Its role is to support growth by supplying oxygenated blood and essential nutrients to the baby.⁶ Once the placenta has served its purpose and the baby has adapted to life outside the womb, the body expels the placenta after birth.¹ It is the only organ we grow, use for a few months, and essentially discard (assuming it is not kept for personal consumption or usage, i.e., placenta encapsulation).⁷

Related: Placenta Encapsulation: What You Need To Know

How the Placenta Supports Pregnancy

From roughly the end of the first trimester, the placenta is fully formed and ready to nourish and support the baby’s life in the womb. What’s known as the “maternal side” attaches to the uterus, while the baby remains connected to the “fetal side” throughout pregnancy.¹ One of the placenta’s most important roles is ensuring that maternal and fetal blood never mix, thanks to the placental membrane.⁷

Below is a closer look at the placenta’s three main structures:

The Placenta

This essential organ can attach to any part of the uterus and grows and moves with the growing uterus.¹ Some mothers may notice they don’t feel their baby kick as soon as other pregnant colleagues or friends if they have an anterior placenta. This is where the placenta attaches to the front of the uterus. Kicks will become more frequently felt from 20-ish weeks in pregnancy when a mother has an anterior placenta.⁸

The placenta may sometimes attach relatively low, causing early pregnancy concerns. It is important to note that a low-lying placenta and placenta previa are two different things. A low-lying placenta is attached close to the opening of the uterus.¹ Often, this corrects itself as the uterus grows and expands upwards, moving the placenta.⁷ A placenta that completely covers the uterus’s opening, resulting in the need for a surgical birth, is called placenta previa. This condition is rare, affecting only one in 200 women during their third trimester.²

The Umbilical Cord

While it’s anyone’s guess where the placenta will attach itself to the uterus, the same can be said for the umbilical cord insertion in the placenta. There are many varieties of cord insertions, but the vast majority of insertions are central and eccentric insertions.³

This amazingly long and strong cord connects the baby and the placenta. The umbilical cord houses three blood vessels. One is a vein that brings oxygenated, nutrient-rich blood from the placenta to the baby. Two arteries carry waste from the baby back to the placenta, where the mother can excrete it.⁹ The three vessels are vital and protected from being squashed or compressed by a substance called Wharton’s jelly.^4,9 Many scans show the baby playing with the umbilical cord, wrapping their little hands around it, etc.

The Membranes

Attached to the organ are two strong membranes: the amniotic membrane and the chorion. The baby, the umbilical cord, and amniotic fluid are within these membranes. These membranes, like the placenta, will grow throughout the pregnancy.^7,9 Once the time for birth comes, there will be a tear in the membranes, and amniotic fluid will leak. Approximately one in 80,000 babies will be born en caul, which means the membranes will be fully intact at birth.⁵

The placenta is an incredibly complex and often overlooked organ that plays a vital role throughout pregnancy. As more parents become curious about it, many providers now offer bedside “placenta tours” after birth.

In many cultures, the placenta is referred to as a baby’s first friend. It supports, protects, and nurtures life long before birth. The next time you give birth, consider asking your provider to show you your placenta. It’s an impressive reminder of just how much your body is capable of.