Pregnant, What’s happening to me?!

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So you found out you are pregnant! Congratulations, I’m sure you now want to know what to expect in regards to your own body. This is a real hard topic to put into “non-nursy” language so I will try my best to help you understand. Don’t hesitate to email me or comment below if you need clarification on anything!

Pearson Education, Inc female anatomy pregnantThere are many things going on simutaneously to your body when you are pregnant. Almost every major body system is compensating for the amazing baby production you are undertaking. Let’s look at each body stystem and explore the physiological changes that are occurring.

The Reproductive System

    • The uterus increases to 20 times its pre pregnancy size.  The volume increases from holding less than 2 teaspoons to 1 gallon (10ml to 5L).
    • The uterus changes in shape from that of a pear to that of a soft globe that enlarges and rises out of the pelvis by the end of the first trimester.
    • The cervix softens in response to increased vascularity, edema, hypertrophy and hyperplasia. (Goodell’s sign).
    • A mucus plug fills the cervical canal soon after conception.
    • The ovaries stop ovulation due to suppression of FSH (follicle stimulating hormone).  Your body produces progesterone and estrogen for 6-7 weeks after conception to help maintain the pregnancy, and then after the placenta will produce the progesterone to maintain the pregnancy.
    • Your breasts begin noticing changes soon after conception.  I’ve known women who first know they are pregnant due to breast changes they are experiencing.  Breasts will change in size, become nodular, the skin will appear thinner, blood vessels become more prominent, the areola darkens and the nipples become enlarged and more erect.  Internally the alveoli begin producing colostrum (your first milk).

Non-Nursy Takeaway…Your uterus is growing, your cervix is softening, your ovaries are not ovulating, & your breasts are getting bigger, developing nodules, have thinner skin, showing more blood vessels, darker areolas and larger more erect nipples

The Cardiovascular System (The Heart)

  • Hypervolemia occurs- Your body produces more blood to circulate in the body, this alone affects many systems.  Increased vascular volume, the increased amount of blood can be up to 1500ml (thats a liter and a half!) this in turn creates a hemodilutional state. Your plasma increases 45-50% and your RBC’s increase 20-30%.
  • Beginning in the first trimester and peaking around week 32-34 women experience physiological anemia of pregnancy – this tends to normalize by 6 weeks postpartum – blood work is normally done at your postpartum checkup that occurs about this time. No treatment is necessarily needed.
  • Murmurs can often be heard during pregnancy due to increased amounts of blood flow.
  • Cardiac Output (blood volume pumped by the ventricles over 1 minute) increases by 30-50%, this usually levels out at 28-34 weeks. The body compensates for this by decreasing systemic vascular resistance or hypertension occurs.
  • Venous pressure increases due to the growing uterus placing pressure on the inferior vena cava. This in turn decreases venous return, decreasing cardiac output, creating edema (swelling), and vericose veins.  Laying on your left side is optimal for cardiac output and uterine perfusion.
  • Anatomically speaking the heart is actually displaced as pregnancy advances. It averages a 12% increase in size.  It moves up, forward and left.

Non-Nursy Takeaway… Your body produces a significant increase in blood, your heart is working harder to compensate for baby production, you might develop murmurs, edema, &/or varicose veins.

Hematological System –  The Blood

    • Hyper-coagulation occurs in all pregnant women
    • Your blood increases in fibrinogen (the main clotting factor) by an average of 50%.
    • Your blood has a decrease in fibrinolytic activity (hard time breaking down)
    • The changes to your blood makes you at an increased risk for clots, thrombosis and alterations in coagulation (DIC – Disseminated intravascular coagulation)
    • Leukocytosis – granulocytes primarily neutrophils range by 10,000-12,000/uL on average & peaking at 25,000/uL during labor

Non-Nursy Takeaway…due to increases in the chemistry of blood, you are at an increased risk for clots, thrombosis and DIC (which you don’t have to completely understand to know its not good…)

Respiratory System (The Lungs)

    • Your lungs compensate throughout pregnancy by increasing oxygen consumption to help the fetus. Oxygen requirements increases by 15% – 20% to supply the uterus and placenta and to compensate for the increased cardiac activity.
    • You experience increased minute ventilation , which can create mild compensated respiratory alkalosis, increasing PaO2, decreasing PCO2, and increasing renal bicarbonate excretion, this can be evident by deeper breathing.
    • Increase in tidal volume (volume of air exchanged with each breath)
    • Your lungs decrease functional residual capacity (the amount of air left in the lungs after you exhale)
    • Anatomically speaking your lungs are displaced upward as pregnancy advances, the rib cage expands 2-3 inches & the diaphragm elevates 1.5 inches.

Non-Nursy Takeaway…You use more oxygen while pregnant, often deeper breathing occurs. Lungs are displaced & your rib cage expands

Genitourinary System

    • Hypervolemia causes increased renal blood flow which in turn increases your GFR glomerular filtration rate, increases creatine clearance (which is reflective of kidney function)
    • Increased urinary glucose excretion due to decreased absorption
    • Hydroureter and hydronephrosis can occur, which leads to ureter hypoplasia/hypertrophy from decreased tone from elevated progesterone (smooth muscle relaxer)
    • Anatomically speaking your genitourinary system can be displaced during pregnancy from the growing uterus and cause backward flow of urine and urinary stasis which greatly increases your risk of UTI’s (Urinary Tract Infection) and increases the danger of pyelonephritis.
    • Increased urinary frequency due to pressure from the growing uterus and later in pregnancy – pressure from the engaging fetal part.
    • Urine output also increases by 25% during pregnancy.

Non-Nursy Takeaway…Your kidneys are working hard, growing uterus can displace bladder and this can increase your chance of getting an urinary tract infection, you also have to pee more often 🙂 

Gastrointestinal System – 

    • Gums become hyperemic, swollen and soft.  They have a tendency to bleed from elevated estrogen.
    • Some women experience excessive saliva (ptyalism), this is sometimes a result of women who decrease swallowing associated with nausea and vomiting.
    • Other women report that pregnancy resulted in a dry mouth (xerostomia)
    • A relaxed cardiac sphincter can cause pyrosis (heartburn) and esophageal regurgitation (acid reflux)
    • Smooth muscle relaxation occurs from increased progesterone and can lead to slowed GI tract motility (meaning fluids and nutrients stay in the intestines longer, which can result in constipation)
    • Anatomically the stomach and intestines can be displaced from the growing uterus.
    • The gall bladder has an increase in volume and decreased muscle tone.  The emptying time can take longer, which can result in gallstones.  Retained bile salts can lead to pruritus.
    • Hyperemsis gravidarum – extreme nausea and vomiting can be related to increased amount of hcG
    • Hemorrhoids can develop related to an increase in venous pressure

Non-Nursy Takeaway…Gums might bleed, you can have excessive saliva, dry mouth, heartburn, acid reflux, constipation, gall stones, pruritus (itching), Truly all fun?!

Musculoskeletal System – The Bones & Muscles

    • Increase in progesterone and a hormone relaxin creates relaxation and increased mobility of the joints and leads to a characteristic waddling gait.
    • Distention of the abdomen and a change in one’s center of gravity can cause Lordosis – increase in lumbar inward curvature.
    • Diastasis Recti- Abdominal muscles separate from the pressure of the enlarging uterus

Non-Nursy Takeaway… You will begin to have a waddling gait, find a new center of gravity & your abdominal muscles will possibly separate (yikes!)

Integumentary System – The Skin

    • Hyper-pigmentation due to estrogen and progesterone
    • Chloasma “mask of pregnancy” decreases after delivery
    • Linea Nigra can appear as a line from umbilicus to mons pubis
    • Nipples, areolae, axillae, vulva and perineum all darken
    • Striae Gravidarum – weakened connective tissue can result in stretch marks in the breasts, abdomen, thighs, and inguinal area.
    • Some women may report an increase in hair growth during pregnancy.

Non-Nursy Takeaway…your skin might be darker, might develop redness across your face,a dark line might appear on your belly as well as stretch marks occurring on different parts of your body

Did you experience most of these?  

Thanks, Nurse Kelly

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    If you are newly pregnant or trying to conceive, you have many questions about what to expect. How will your body change? What’s happening inside you? Our week-by-week guide will help you through your nine months of pregnancy so you can be a smarter, more confident, more prepared mom-to-be. Each week offers information about your body and the baby’s as well as helpful advice you can use throughout your pregnancy. Let’s start with a peek inside the womb.

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