13 epic facts about the placenta

Ah… the placenta. A truly unique organ that develops within your uterus during pregnancy. You may already think it’s incredible (spoiler: it is) or it might gross you out (also fair). However you feel about it, it sure is fascinating. Wherever you sit on that scale, read on for thirteen wild facts about the placenta.

1. The placenta looks kind of… weird.

A round or oval shape, the placenta sorta resembles a juicy parachute (er, yummy…?). It’s about 25cm in diameter and 2.5cm thick, weighing around 600g, and has two sides that are different colours. The side attached to your uterus is a deep reddish-blue (kinda how we picture a lot of our organs) and the side facing your bub is… grey. Yikes. 

After it’s delivered you’re left with an internal wound the size of a dinner plate. Take that as an excellent excuse to rest up, Mama (as if you didn’t have enough reason already)!

2. The placenta is part of your pregnancy from the start.

Whilst there are many different stages of pregnancy, this particular journey starts as early as day five, when the very first cluster of cells (known as a blastocyst) divides into the fetus and the placenta. 

Between days 6 and 10, implantation occurs. This is when the blastocyst attaches itself to your uterine wall and begins developing into your little cutie-to-be. 

3. The placenta can attach to different places within the uterus. 

The position of your placenta will be confirmed via ultrasound at around 20 weeks, although it can also move around until about 32 weeks! Indecisive much? The placenta can be posterior (back wall of the uterus), anterior (front wall), fundal (up top) or lateral (the right or left side). 

An anterior placenta can impact how well you can feel your baby’s kicks, acting as a sort of cushion between you and your bub. 

Meanwhile, one that’s low lying is referred to as a partial or complete placenta previa. This can cause symptoms such as bleeding and usually means you’ll need to deliver via c-section.

4. Your placenta is responsible for nourishing your baby.

Your blood – yes yours! – passes through the placenta, sending in all the goodies like oxygen and nutrients via the umbilical cord. At the same time, it filters out nasties such as waste products, carbon dioxide and even certain bacteria, in order for your bub to grow and develop healthily. What a doll.

5. The placenta produces hormones.

The ultimate multi-tasker, it’s also an endocrine gland, meaning it plays a big role in hormone production, including oestrogen, progesterone and lactogen. So you can blame your placenta when you lose it at your partner for chewing loudly/breathing/existing.

6. The placenta doesn’t let Mum and baby’s blood mix. Ever. 

Maternal and fetal blood never mix as the placenta acts as a barrier, keeping them separate. This nifty process stops the mother’s body from rejecting the fetus as a foreign object and allows you and your baby to coexist safely.

7. The placenta is made up of DNA from the mum AND dad.

This is where things get wild. The placenta genetically belongs to your bub, meaning it is made up of DNA from both the biological mother and father. Dad’s genes can even theoretically affect the maternal brain, having a say on how attentive you may be as a mum once your little one is Earth-side. Apparently, the patriarchy still reigns… ha. 

8. The placenta needs to be delivered too.

How the placenta is delivered depends on how you just delivered your baby. You might deliver the placenta vaginally, known as the third stage of labour. If you have a c-section, your obstetrician will remove it for you, also through the sunroof. It will be checked after delivery to make sure it’s in one piece, as retained placenta fragments can cause problems such as infection, bleeding and breastfeeding difficulties. 

9. The placenta helps kickstart your baby’s immune system.

By transferring antibodies (sickness fighting super cells) from your body to your growing baby, your placenta gives their immunity a sweet kickstart. These cells can last for the first several months of your babe’s life earth-side (this is also part of the reason for being recommended certain vaccines in pregnancy).

10. Twins can have either one or two placentas.

They say twins share everything, and some even go halves on a placenta, although they’re in the minority. Twins with a single placenta will be identical, with some developing in two amniotic sacs and some sharing just one. These scenarios can increase the risk of certain complications such as nutrient imbalances or something known as twin-to-twin transfusion syndrome.  

11. Some people eat their placentas.

Whilst you might be aware of placenta nutrition facts in terms of benefiting your bub, you might not know that it’s become increasingly popular to ingest it after birth. The things we do for our babies, eh? 

We went down a rabbit hole of placenta encapsulation facts and learned that while the supporting science is lacking, the benefits are pretty appetising (too much?) – including improving maternal mood, energy, and milk supply, and lowering postpartum bleeding. However, it should be noted that there are risks involved so before you consider chowing down, make sure you’ve done a crash course on the safety of eating your placenta. 

12. The placenta has spiritual and cultural significance.

Within many cultures, the placenta is considered spiritually important and you can read about some of the rituals and traditions here and here.  Many birthing women find spiritualising this aspect of birth enriching, but policy surrounding birth can be limiting, particularly within the western medical environment. 

13. Placentas can save the world.

Research has found that the placenta contains more stem cells than umbilical cord blood, and that they can be safely harvested post-delivery and used in a number of medical research and patient treatment settings, one of which is cancer research. Not all heroes wear capes, friends.

So, there you have it. This wondrous little life-giving organ can do more than just grow you a baby or two. What an absolute boss!

Read next: Are you really going to eat that? The rising trend of placenta encapsulation

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