Placenta Tour - Just The Basics

If you are at all squeamish, this might not be the blog post for you.

Be warned… You will see blood


But for the “Placenta Curious”, this is your place to learn! There are two sides to every story and the placenta is no different. There is the maternal side and the fetal side. And they both have a story to tell. And, that cord? Wow! It has an amazing story to tell, too, but that is for another blog, found here.

The placenta starts to develop and grow shortly after the egg is fertilized. It attaches to the uterine wall as soon as the fertilized egg implants in the wall of the uterus. (You may even have experienced a little “implantation bleed” when that happened.) Did you know that when you take that pregnancy test and you get a positive, that is because the placenta is producing human Chorionic Gonadotropin (hCG)? Yep, that placenta gets to work early on in your pregnancy.

So here is a crazy thought! The placenta is the only organ that has TWO blood circulatory systems and TWO beating hearts pumping blood to it. Say, What?!!! Also, your placenta works hard for you and baby:

  • Acts as a filtration system to take oxygen rich blood, antibodies and nutrients TO baby and waste and deoxygenated blood AWAY from baby.

  • Produces and releases hormones, such as progesterone, estrogen, oxytocin, human chorionic gonadotropin and human placental lactogen. By about 10 weeks, it takes over the production of progesterone and this is why at around this time, your morning sickness symptoms begin to go away. HURRAH!

  • By about 12 weeks, your placenta is fully formed and takes over the job of nourishing your baby.

So - here we go. As I promised. Just the Basics:

The number one question I get:

WILL IT HURT TO DELIVER MY PLACENTA? Your placenta is usually delivered by about 30 mins of delivery of your baby. The placenta is soft and has no bones in it so it will feel very different from your baby…Kind of Blobby (if that is a word?). During this “Third Stage of Delivery”, you may feel some tugging with “active management” so it might be worth asking for “passive management” of the placenta delivery unless medically necessary (such as a known increased risk of hemorrhage) to actively manage it.

You may also be surprised that your uterus will still contract (after pains) after your baby is born. There are two reasons for this:

  1. To expel your placenta

  2. To stop the blood flow from the wall of your uterus where the placenta was attached.

In fact, you may experience those after-pains for awhile after birth, which seems rather unfair, but this is nature’s way of stopping you from hemorrhaging! If you are breastfeeding, you may get contraction when baby begins to suckle because of the release of oxytocin (which is the same hormone that caused your labor contractions)

Placenta Deets:

SIZE: Usually about the size if a small salad plate or waffle. You will see in the “Placenta Tour” video (below) that I use my hand to gauge the size of that particular placenta.

PLACEMENT: The placenta is usually attached to the top or side of the uterus.

SHAPE: Usually round but can come in many different shapes: Heart shaped, bi-lobed, twin placentas may be fused, etc.

WEIGHT: An average of about 500 grams or 1 pound.

What’s important to remember is that the size of your placenta is also the size of the wound on the side of your uterus and where your postpartum bleeding is coming from. In fact, I often say that your placenta will “tell on you” if you have been too active in those first days because you will bleed more. It’s the placenta’s way of saying, “hey, go sit in that chair and rest Momma!” ( Tip- if you are bleeding enough as to fill a pad more than one per hour, please call your care provider. That is too much bleeding!)

The Baby’s side of the placenta

This is the baby’s side of the placenta is shiny and smooth

Things we look at on the Baby’s side:

CORD INSERTION: Usually central but there are many variations. The placenta in the pix above has what is called a “Battledore” or “Marginal” insertion (the insertion of this cord is near the side of the placenta). We also look to see if the cord vessels are fully encased in the Wharton’s Jelly which is the white part of the cord.

CORD LENGTH: The average cord is 55 cm long (about 20 inches).

CALCIFICATIONS are shown and felt as small, gritty white spots made from calcium deposits in the placenta and are considered normal findings if seen after the 37th week of pregnancy. More than 50% of placentas have some degree of calcification by full term.

AMNION & CHORION: This is the sac (also called the bag of water) that your baby was living in during your pregnancy. There are actually 2 layers to it! The inner most sac is the Amnion. The outer sac is the Chorion. You will see them more easily in the video below.

MECONIUM STAINING: This may be seen as a greenish hue to the shiny membranes of your baby’s sac. Its presence indicates that your baby passed a stool while still in the bag of water.

The Mother’s side of the Placenta

This is the mother’s side that was attached to the uterus. It’s bumpy and rough feeling

Things we look at on the maternal side:

Cotyledons - If you look at the mother’s side of the placenta, you see there are many “blobs” of placenta tissue with what looks like valleys in between them. That is normal. When examining a placenta, we look to see if it is “intact” - meaning it appears that there a no missing cotyledons. This is important because missing parts of the placenta may cause hemorrhage and /or infection, either soon after birth or even days or weeks later.

Calcifications (see above)


WARNING: The video below will show a placenta and Blood.

This is the “placenta tour” that I offer to show to parent’s after the birth of their baby. A big Thanks to this momma who gave her permission to share her tour with you.

I hope that you found this of interest! I am interested to know if you saw your placenta. Did you encapsulate your placenta? Where the surprises for you regarding your placenta? Please share with us in the comments!

References:

  1. Ernst, L. M. (2018). Maternal vascular malperfusion of the placental bed. APMIS, 126(7), 551–560. https://doi.org/10.1111/apm.12833

  2. Ma, L. X., Levitan, D., & Baergen, R. N. (2020). Weights of Fetal Membranes and Umbilical Cords: Correlation With Placental Pathology. Pediatric and developmental pathology : the official journal of the Society for Pediatric Pathology and the Paediatric Pathology Society, 23(4), 249–252. https://doi.org/10.1177/1093526619889460

  3. Panti, A. A., Ekele, B. A., Nwobodo, E. I., & Yakubu, A. (2012). The relationship between the weight of the placenta and birth weight of the neonate in a Nigerian Hospital. Nigerian medical journal : journal of the Nigeria Medical Association, 53(2), 80–84. https://doi.org/10.4103/0300-1652.103547