Maternal Adaptations to Pregnancy

Part 7: Skin and Teeth 

• Palmar erythema is seen in pregnant women. This is caused by estrogen which has angiogenic properties.
• Striae gravidarum are “stretch marks” and they are caused by the skin stretching due to the increased size of the uterus, not because of weight gain.
• Hyperpigmentation is also common in several places on the body. This is also called melasma.
  • A linea nigrans can form. I’m sure you all remember the derm lecture in Core where we talked about that? No? Well, it’s a dark line running down the center of the abdomen.
  • The areolas darken and there can be a mask-like darkening on the face.
• Acne is common, particularly in younger patients. This is due to an increase in sebum production and sweating.
  •  A patient may ask what can be done for this, and unfortunately, the answer is, “not much.” You absolutely cannot give acne medications. They are all contraindicated in pregnancy.
  • Accutane is the worst (and the most powerful acne med). It causes severe birth defects.
• Women don’t normally complain about hair changes during pregnancy, but in the months afterwards.
  • During the pregnancy, less hair is in the resting phase. Although it was not said specifically, I’m guessing that means your hair is actually thicker than it would normally be.
  • After delivery, hair follicles are recruited back to the resting phase. This causes thinning of hair and hair loss which can be quite significant. This is a common complaint of 2-4 months post-partum.
  • 6 months to 1 year after delivery, the hair follicles sort themselves out and normal growth returns.
• There is an increase in gingival disease during pregnancy. This is not an increase in cavities (dental caries), but rather due to gingival hyperplasia.
  • These enlarged sections of the gums can bleed significantly. If necessary, they can be excised.

Part 8: Breast and Musculoskeletal Changes
 

Breast Changes

• There is an increase in the size of the breasts of 25-50%.
  • This change occurs mostly in the first trimester and can leave the breasts exquisitely tender.
• The areolas enlarge and become darker.
• There is increased blood flow to the breasts.
  • This is most significant towards the end of pregnancy as the breasts prepare for lactation.
  • The blood flow at this time can be 2-3x greater than normal.
• The breast tissue itself matures and ductal growth can be seen. This was talked about in Dr. Hameed’s lecture.

Musculoskeletal Changes

• Lumbar lordosis occurs due to a laxity of joints (caused yet again by progesterone), but also because of the growing uterus.
• There is ligament laxity all over, but particularly in the symphysis pubis. This is to prepare the body to pass a huge bowling ball head out a very tiny opening; everything needs to stretch.
• You need to warn your patients about these changes because their center of gravity will change during this time. They need to know they won’t be as stable on their feet as they’re used to being.
• Calcium mobilization from bone is increased.
  • Basically, the baby is stealing your bones, so all pregnant women need to be on calcium supplements.

Part 9: Reproductive Tract, Abdominal Wall, and Endocrine Changes

Reproductive and Abdominal Changes

• Vulvar varicosities develop due to *gasp!* progesterone…and (wait for it) pressure effects from the growing uterus. It’s like you never would’ve guessed!
  • Hemorrhoids can also develop for the same reasons.
• Vaginal discharge is normal at any time, but can be increased during pregnancy.
  • This is due to increased blood flow (another shocker) and increased exfoliation of cells.
• Myometrial hypertrophy was stressed in lecture as something we will see “on an exam.” I’m pretty sure Dr. Pompeo meant the boards, but I wouldn’t be surprised if it wound up on our exam either.
  • The uterus grows from 70g before pregnancy to 1100g at term. This is not due to new growth, but rather, the hypertrophy of pre-existing cells.
• Diastasis recti can occur as the uterus grows if it separates the rectus abdominus muscles in the midline. It may look like a hernia because you’ll see a bulge in the abdominal wall, but it is not. It resolves after pregnancy.
• Hernias also commonly occur in pregnancy, but they are of little clinical concern at the time.
  • The growing uterus displaces the bowel and preventing it from entering the hernia sac.
  • There’s actually a decreased risk of incarceration and surgical repair when pregnant.
  • The only problem is if a loop of bowel or omentum is tethered to the hernia sac and then incarceration is more likely.

Endocrine Changes

• Carbohydrate metabolism gets all messed up (remember when I talked about extra glucose in the urine?)
  • Human placenta lactogen is made, unsurprisingly, in the placenta. It increases insulin resistance.
    • The bigger the placenta gets, the more HPL synthesized and the higher the insulin resistance.
    • This can cause glucose intolerance.
  • The fetus gets glucose from the maternal blood, through the placenta. It’s always hungry for more and acts as a glucose sink.
    • Because the baby is stealing all the glucose, the mother will have a more profound hypoglycemia when fasting, leading to headaches and fatigue.
  • After a meal, a pregnant woman will be hyperglycemic due to her insulin resistance. Before a meal she will likely be hypoglycemic due to the hungry baby.
    • In order to check for glucose intolerance and diabetes, a blood sugar test needs to be done after eating. No matter what, the woman is likely to be hypoglycemic beforehand.
    • This is somewhat confusing, but it is explained more in a lecture from tomorrow.
• Lipid metabolism and synthesis are increased, as mentioned previously. This is so the baby can make hormones.
  • Incidentally, does anyone remember how you make a hormone?
    • You don’t pay her.
• Thyroid function does not change.
  • However, when you check blood levels of T3 and T4 they seem elevated.
  • Remember, the liver is making more binding globulins so more T3 and T4 are going to be bound in proteins.
  • The thyroid makes more T3 and T4 in order to maintain free levels of hormones.
  • Instead of checking for total T3 or T4 to test thyroid function, free T3 and T4 or TSH are checked.
• The adrenals also increase the release of cortisol during pregnancy.
  • I guess a pregnant uterus is sortof like the ultimate Cushings…Talk about central obesity!

Part 10: Case Recap
 

So…looking back at that case we had in the beginning, what was normal and what wasn’t?

• Some fatigue and occasional headaches, esp when she hasn’t eaten
  • Normal – due to hypoglycemia from the baby acting as a glucose sink.
• Short of breath after moderate exercise
  • Normal – due to pulmonary changes leading to exercise intolerance.
• Her gums bled when she brushed her teeth
  • Normal – gingival hypertrophy.
• Nasal congestion with no other symptoms of URI
  • Normal – due to increased blood flow. Not related to allergies or URI.
• Nausea and vomiting earlier in the pregnancy
  • Normal – unknown etiology, but maybe related to beta-HCG levels.
• A lot of heartburn
  • Normal – gastroesophageal reflux due to relaxation of the sphincter by progesterone.
• Darkening of the skin around her face and a line was visible on her belly, as well as stretch marks
  • Normal – common skin changes called “melasma.” She is describing a facial mask and a linea nigrans.
• Her breasts were sore
  • Normal – due to increase in size.
• Grade 1-2 SEM at the left sternal border
  • Normal – an innocent flow murmur due to increased blood volume.
• WBC 13 (elevated), Hgb 11, Hct 32 (both low), Plt 220 (slightly low)
  • All normal – due to increased granulocytes and physiologic anemia of pregnancy.
• Udip shows nitrates and leukocytes
  • Abnormal! – While a common problem in pregnancy, a UTI is not normal.

Return to Section 1 of Maternal Adaptations to Pregnancy 

Return to Section 2 of Maternal Adaptations to Pregnancy 

Back to the Reproductive System Index