All About the Placenta

In recent years placentas have become more and more talked about in birthing communities. Options for what to do with the placenta after the birth have grown and become more well known. Placentas are quickly becoming a bit of a “hot topic”, but many folks still have questions about how they work, what they do, and what to do with them in the postpartum period. Hopefully, this blog will help to answer some of your questions!

Photo by

What is the placenta? 

The placenta is an organ that develops with the pregnancy and is the source of nutrients and oxygen to the growing fetus. It is generally circular and flat. Developing shortly after conception, the placenta is not complete and attached to the maternal wall until 12 weeks gestation. There are many steps that occur in the first 12 weeks of gestation as the uterus changes and both the placenta and fetus develop rapidly. The umbilical cord runs from the placenta (usually near the middle) to the baby, allowing mother’s  nutrients and oxygen to pass to the baby, as well as the baby’s deoxygenated blood and other waste products to be sent back to the maternal body to be filtered out.

The placenta is attached to the uterine wall by small units of tissue and blood vessels. These units are called “cotyledons” and they are responsible for stabilizing the placenta, as well as facilitating the exchange of nutrients and oxygen.

The side of the placenta that is attached to the mother is called the “maternal side” and the side that the umbilical cord attaches to is called the “fetal side. The fetal side is covered in two layers of membranes; the inner layer is called the amnion and the outer layer is called the chorion. These membranes go around the developing baby and contain the amniotic fluid that the baby develops in. When a woman’s water breaks it is really the membranes breaking and releasing amniotic fluid.

Vascular Biology of the Placenta via

The placenta has two blood supplies; one being the maternal blood supply (uteroplacental), the other being the fetus (fetoplacental). The uteroplacental blood flows into the placenta from the maternal arteries connected to the uterus. These arteries widen throughout pregnancy, gradually increasing the amount of blood flow to the uterus. The maternal arteries bring the oxygenated blood to the cotyledons and a process of diffusion occurs. Deoxygenated blood is pushed toward the outer edges of the uterus and into the uterine veins which carry it back up to the heart to be recirculated. The oxygenated blood then moves through the placenta which filters out non-useful substances and sends oxygen and nutrients onto the fetus.

The fetoplacental system occurs through the umbilical cord into the placenta. In the cord there are two arteries and one vein. The arteries bring oxygenated blood from the placenta into the fetus. The vein carries deoxygenated blood and waste products from the baby back to the placenta and onto the maternal system. One of the most amazing things about the placenta is that it contains both fetal and maternal blood, but the majority of the time these two separate blood supplies don’t mix. The exchanges of oxygen, nutrients, deoxygenated blood, and waste products all occur through the capillaries in the cotyledons.

Timeline of Placenta Development and Attachment via the University of Columbia:

After Fertilization –Embryonic Period 

  • day 4-5 blastocyst reaches uterine lumen
  • day 5-6.5 apposition, syncytiotrophoblast forms
  • day 7 adhesion/implantation
  • day 8 hCG detectable in mother’s serum
  • day 9 embryo completely implanted, lacunae in syncytiotrophoblast
  • day 11-13 primary stem villi
  • day 14 cytotrophoblasts partially occlude spiral arteries, maternal blood circulates (plasma only, no cells)
  • day 16 secondary villi by invasion of extraembryonic mesoderm
  • day 21 tertiary villi (fetal vessels)
  • 8 weeks end of embryonic period
  • 12 weeks maternal whole blood (cells and plasma) flow to placenta via converted spiral arteries

*Please note that the above timeline uses very medical terms, as it is taken from a medical text studying embryology. The definitions of these terms are in this link on pages 17.2-17.3

If you would like a more visual explanation of the role of the placenta the maternal/fetal blood flow please see this Khan Academy video “Meet the Placenta!”

What happens after the birth of the baby?

Photo by

Photo by

There are several changes in a baby’s circulatory system that have an affect on the functioning of the placenta. While in utero there are several aspects of the fetal circulatory system that differ from the neonatal (newborn) circulatory system. There is less blood flow to the fetal lungs because while in utero the lungs are filled with fluid and are not needed for oxygenation. There is a “flap” or valve in between the right and left atrium of the fetal heart that allows for blood flow between the atrium rather than to the lungs. There are also several arteries and blood vessels connected to the fetal aorta and vena cava that allow for blood flow to and from the umbilical arteries and vein which in turn go to the placenta. In the hours and days following birth these vessels will close off and shut down as the circulatory system of the baby goes from an “open system” (involving the fetal system in connection to the uteroplacental system) to a “closed system” (being only the organs inside of the baby). For more information about the circulatory system before birth and the circulatory system after birth please see the Khan Academy “Fetal Circulation Right Before Birth” and “Baby Circulation Right After Birth” videos.

In conjunction with the changes in the circulatory system of the baby there are also changes occurring in the umbilical cord and in the uterus that lead to the stoppage of blood flow through the umbilical cord and to the detachment of the placenta from the uterine wall.


Photo from

The umbilical cord gradually stops pulsating after the birth because the blood flow within it is decreasing. This is because the baby’s circulatory system is sending less blood to the cord, the maternal system is cutting off blood flow to the placenta, and the colder air temperature is stimulating the cord to contract and clamp down on it’s own.

As the blood flow to and from the placenta decreases the uterus is also continuing to contract and shrink down. The shrinking of the uterus leads to smaller surface area for the placenta to be attached to and the contractions themselves cause the blood vessels connecting the placenta to the uterine wall to clamp down and “let go”, thus the placenta begins to separate from the wall of the uterus. During this process the center of the placenta often releases from the uterine wall first and a blood clot forms behind it. As the outer edges of the placenta release, the placenta will become fully detached and will be ready to be born. The above diagrams show the development of the clot and the separation of the placenta. Once the placenta is fully detached it is ready to be born through a combination of uterine contractions and maternal effort (pushing). The membranes that had been holding the amniotic fluid and the baby will remain attached to the placenta during this process and will be born with the placenta. After the placenta is born the midwife will examine it to make sure it is complete and no cotyledons or other parts have remained in the uterus. Now that both the baby and the placenta are no longer in the uterus, it will continue to contract and shrink down, gradually getting back to a pre-pregnancy size.

What can be done with a placenta after the birth?

There are many options for placenta care after birth and not every option is a good fit for each family. Families are encouraged to choose the option that fits their lifestyle the best.

  • Dispose of your placenta. Some folks don’t feel the need to keep the placenta or use it in any other way after the birth. After your birth the placenta will be double-bagged (placed in 2 airtight Ziploc bags). It can then be placed in the garbage. Keep in mind if you give birth on a Sunday and your garbage is not picked up until Friday you may want to place it in your freezer until the night before trash pick up to avoid any odors.
  • Planting your placenta. Some families choose to plant their placenta; under a tree, under a stone, or simply in the yard. If you give birth a time of year where the ground is frozen you can store your placenta in your freezer until spring.

    Photo from

    Consumption. There are many options for placenta consumption. Consumption has been used in many traditional cultures for many, many years. There are not many studies on the effects of this, however some of the believed effects are increased energy, lowered rates of postpartum depression, increased milk supply, and lessened time of bleeding after birth.

    • Encapsulation: This involves dehydrating the placenta, grinding it down to a powder and putting the powder into pill form for the mother to consume during the postpartum period. There are two encapsulation techniques that are commonly used. The Traditional Chinese Method (TCM) calls for steaming the placenta with specific spices before dehydrating while the Raw Method does not involve any steaming before dehydration. The TCM method is believed to have more of a warming effect and allow for a slow release of energy. This can be beneficial to new moms in that it gives energy without giving so much that women over do their activity level early on. The TCM method is also thought to preserve the nutrients of the placenta for longer periods of time. In comparison, the raw method is believed to provide a stronger burst of energy. This can be beneficial for some women; particularly those who have had greater blood loss. Raw food advocates tend to choose this method as they believe heating foods destroys nutritional value. Each woman should choose the method best suited for her and her needs. For more information please see the Independent Placenta Encapsulation Network.
    • Tincture: This form of consumption involves placing either placenta powder or raw placenta in either brandy or vodka and allowing it sit in a jar for 6 weeks. After 6 weeks the solids are strained out and the mother can take 10-40 drops of the tincture daily to help with mood and milk supply.
    • Other consumption methods can include smoothies, dehydrating, or cooking. There are many, many recipes and ideas for this online if this is something you are interested in. If you do choose to consume your placenta as a food please remember it needs to be stored safely. It can remain in the fridge for 24-36hrs but then should be placed in the freezer. For more information about placental consumption please see the American Pregnancy Association post, and Placenta Wise.

    Photo from Art of Patience

    Placenta Prints. This can be done in several different ways. Making a print of the shape of the placenta can be fun for families to do as a group activity (including older children) or can be done by other birth workers. Prints can be placed in baby books, framed and hung on walls or whatever else you would like. It is recommended to use either water color paper or heavy weight artist paper (the most important thing is to use acid free paper). The print can be made with the blood that is on the placenta or with ink or paint. If you are also planning to ingest your placenta you need to make sure that the ink or paint is safe to ingest. Food based dyes (i.e. blueberries) are ideal. You can make a print of either side of the placenta. The print can be made by either laying the placenta on the paper, or by placing the placenta on the table (on a chux pad or other barrier) and then laying the paper over it. Some people have found that lifting the placenta off a piece of paper smears the result and they prefer to put paper over placenta.

  • Lucina's Birth Services

    Photo from Lucina’s Birth Services

    Keepsake Cord. Many placenta encapsulators offer this service as well. If you have a very short umbilical cord this may not be an option. However, if the cord is long enough it can be arranged in a shape or word and then dehydrated to hold that shape. Common shapes and words include hearts, the baby’s name or initials or other words requested by the family. These can be placed on a shelf or a shadow box.

If you are interested in having your placenta encapsulated or having any of the other placenta services please see the Minnesota Placenta Encapsulation website and the Childbirth Collective website.

The placenta is a very unique and very vital organ. Christine Northrup the author of “Women’s Bodies, Women’s Wisdom” says this about it:

“The placenta is the quintessential organ of relationship. It is co-created between a mother and her child to sustain a child’s intrauterine life. No one quite understands how the maternal body is able to immunologically tolerate the fetus without rejecting it as foreign. Such tolerance for new life that literally feeds off one’s body is the essence of the maternal relationship. But one needs not be a mother to appreciate the fact that many new relationships begin with one person helping to sustain another. The reward that a mother gets for this is a warm feeling of satisfaction that enlivens and strengths her heart and also changes her brain so that it’s more adaptable.

But there’s a limit to this tolerance. Once a baby has reached full term growth, placental blood vessels begin to calcify and shut down, signifying that it’s now time for the baby to be born into more independent life. Both mother and child go through labor to prepare them for their new roles. The same is true for all relationships. They must undergo constant change and growth–not all of which is comfortable if they are to reach their full potential.

The placenta also models healthy boundaries in relationships. The maternal and fetal blood flow remain separate. The mother–the one who is donating her resources–either providers or withholds blood flow to her baby by the effect of her thoughts, emotions, and behaviors. If she’s angry, stressed, or doesn’t want to be pregnant, her body is likely to create an abundance of stress hormones, which narrow the blood vessels and restrict the blood supply to her child. If, on the other hand, she is relaxed, happy, and feels well cared for, the blood flow to her baby will be optimal.

As they are nurturing and sustaining us, our mothers also need an outer placenta of people, places and things that support and replenish them. Ultimately, each of us has to outgrow our mother’s care and create in turn an outer placenta to provide us with sustainable nourishment at each stage in our lives.”