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Physiological Changes of Pregnancy

Physiological Changes Necessary for Pregnancy

          It is fairly evident that women who are pregnant go through many changes during the course of their pregnancy.  Almost every change happens to either prepare the mother for labor/delivery or promote the development of the baby.  With all the changes that are happening on a daily basis, which ones can be labeled as the most important for the successful outcome of a pregnancy?

According to some authors like Judy A. Forrester, the three most important changes are the development of the placenta, the expansion of the maternal blood volume, and the increased demand on maternal liver function.  Unsurprisingly, major changes like these are intertwined and changes in one affect the others.

The placenta acts as the interface between the maternal system and the baby’s system.  Blood from the mother and infant never combine, but must exchange nutrients and toxins in order for proper function.  When there is a higher concentration of nutrients on the maternal side of the blood, there is diffusion of the nutrients into the baby’s capillaries.  When the toxins and byproducts grow too high in the blood of the baby, they diffuse into the maternal blood supply to be excreted.  Any disruption of this placental exchange can have dire consequences for the developing baby.

In order for the placental exchange to work properly, the placenta must be perfused with blood at all times.  That means that the maternal blood volume must increase by 40-60% in order to perfuse the placenta and still meet the needs of the mother’s organs.  If the blood level falls too low, the nutrient/toxin exchange cannot take place which will negatively impact the developing baby.  In order for the mother to increase her blood level and maintain a higher level of blood, two big changes need to happen.  First, salt must be retained by the body.  The kidneys must reabsorb salt and reintroduce it into the circulation.  In addition, an increased taste for salt develops in the taste buds so more salt is eaten.  Second, there must be an increase in the synthesis of albumin.  Albumin is a complex protein that helps to draw water into the blood circulation.

The synthesis of albumin brings up the third physiological change, which is the increased demand on liver function.  The liver is in charge of the complex process of combining specific amino acids into albumin.  Albumin synthesis is one of the first processes to be lost when there is liver damage.  If the albumin levels in the blood decrease, then fluid leaks out of the blood into the surrounding tissue.  This causes swelling in the tissue and hypovolemia (low blood level) in the circulatory system.  This then cascades back to the first physiological factor by disrupting the placental exchange.

The liver is not just involved in albumin synthesis however.  The liver also is in charge of removal of hormones from the body.  The pregnant female is a hormone generating machine.  A large amount of hormones are manufactured by the placenta and must be cleared from the body.  The issue is that the hormones are fat soluble which makes excreting them through the kidneys difficult.  Therefore, the liver must attach the hormones to other molecules so that they can be properly excreted.  If the hormones are not properly excreted, then there will be a build-up which will force the placenta to stop producing more.  Shutting down this placental function can impact the placenta as a whole.

Finally, the liver is in charge of clearing the colon of toxins.  In a pregnant woman, the digestive system slows to a crawl.  Part of the reason for this is so that every available nutrient can be absorbed from the food she is eating.  One of the byproducts of this slow-down however, is the perfect environment for the production of toxins.  The liver is in charge of cleansing the blood of these toxins.  If the liver is unable to do its job of cleansing the bloodstream, then the level of toxins will increase dramatically preventing toxins from being transferred from the baby to the mother to be cleared.

There are some basic steps that can be done to support these physiological changes.  Number one, drink plenty of water.  This not only will help support the maintenance of blood volume, it will also help insure that the pace of digestion does not get too slow.  Number two, eat plenty of salt.  A pregnant woman has a higher need for salt than a non-pregnant woman.  Number three, eat quality protein.  Pregnancy drives the need for protein up.  A pregnant woman should be consuming between 75 and 100 grams per day.  Protein is the building block of new tissue which is necessary for the baby and is important in the synthesis of albumin for the maintenance of the maternal blood volume.  Finally, avoid processed foods and foods that contain a high number of artificial ingredients and dyes.  These types of food increase the strain on the liver as it tries to filter the blood of toxins.

The body of a pregnant woman is under enough stress from the developing baby.  Avoid adding to it by making smart, healthy choices in the diet to support the physiological changes of pregnancy. At our office we have the knowledge and ability to check the function of the liver, kidneys, and the blood chemistry and correct imbalances naturally. Consider coming to our office for a check-up before or during pregnancy. We would be happy to serve you on your healthy journey.