Changes in glucose and thyroid in preg

Question 1

What % of pregnancy has insulin resistance?

Answer 1

50%

- women must increase insulin secretion (in liver) by 2-3x to maintain euglycemia

Question 2

80% of the energy needs of fetus comes from what?

Answer 2

Glucose

Question 3

Women are insulin ______ in 1st trimester

Answer 3

sensitive

• dont feel low glucose
• women at risk for severe nocturnal hypoglycemia in 1st trimester and wont wake up

Question 4

Women are insulin _____ in late 2nd and 3rd trimester

Answer 4

resistant

• with increase hPL, hPGH, TNFa

Question 5

Prolonged fasting in preg women –>?

Answer 5

Starvation ketosis
(accelerated starvation of pregnancy)
- high risk of DKA in pregnancy
- decreased buffering capacity

Question 6

fasting blood glucose (FBG) in preg women

Answer 6

lower FBG but slightly higher postprandial (after lunch/dinner) glucoses and hyperinsulinemia

Question 7

Gestational diabetes (GDM)

Answer 7

glucose intolerance recognized for the first time during preg.

• occurs LATER in pregnancy 24 weeks
• vast majority are overweight and insulin resistant

caused by:

1. Insulin resistance
2. Impaired insulin secretion
3. Increased hepatic glucose production

*50% of pts with GBM will be declared as having T2D in the next 10 yrs

Question 8

IGT (prediabetes)

Answer 8

diagnosed before 24 weeks and at very high risk for developing T2D post partum

Question 9

thin pt with “gestational diabetes”

Answer 9

latent autoimmune diabetes

LANA or MODY (mature onset diabetes of the young)

Question 10

Why is GDM a burden to mom?

Answer 10

1. More doctor stuff
2. Higher risk of infxn
3. C Section
4. Preeclampsia
5. ~50% MATERNAL RISK OF DEVELOPING T2D in 5-10 yrs
   - target for primary prevention

Question 11

Does breastfeeding increase or decrease risk of T2D ?

Answer 11

Decreases risk

Question 12

Infant of woman with diabetes

Answer 12

1. fatter baby (abdominal) - get stuck in birth canal –> C section or shoulder dystocia
2. Macrosomia
3. infant respiratory distress syndrome
4. neonatal hypoglycemia
5. Hyperbilirubinemia

Question 13

GLucose vs insulin in the placenta

Answer 13

GLucose crosses placenta, insulin doesnt

*baby sees too much glucose –> dev. High insulin –> pancreatic hyperplasia –>
after birth and moms glucose goes away –> baby bcomes hypoglycemic

Question 14

Insulin fx in babies

Answer 14

insulin is a growth hormone causing excess fat deposition

hyperinsulinemia –> pancreatic hyperplasia

Question 15

Long term implications of GDM

Answer 15

1. T1D, T2D, GDM –>
   - increased fetal insulin and leptin
   - neonatal adiposity
   - enlargement of pancreas + heart
2. Appetite regulation –> neonatal obesity and impaired glucose tolerance in childhood
3. Higher risk of devel diabetes in offspring

Question 16

TBG in pregnancy

Answer 16

Increase due to estrogen

• so mom needs to make more TH (T4 to maintain nl free T4)
  (which requires more iodine, plasma vol, and GFR).

Question 17

fetal brain has what transporters?

Answer 17

T4

DO NOT USE T3 IN PREGNANCY

Question 18

Maternal and fetal iodine deficiency –> ?

Answer 18

Cretinism

*recommendation is for preggos to take 250 ug/day

Question 19

Maternal hypothyroidism

Answer 19

most cases due to hashimotos

T4 needed for trophoblast fxn

Most women require 25% increase in thyroid hormone supplements early in gestation

Question 20

Hypothyroidism can do what to the placenta?

Answer 20

1. neurodev. delay
2. preg loss
3. preterm delivery

*remember that T4 needed for trophoblast fxn

Question 21

Causes of hyperthyroidism in pregnancy

Answer 21

1. Graves disease ~85%
2. hCG induced
3. Toxic multinodular goiter
4. Toxic adenoma

Question 22

Post partum thyroiditis

Answer 22

2 phases:

1. hyperthyroid phase : 2-4 mo postpartum
   - destruction of thyroid gland –> release thyroid hormone
2. Continued destruction 4-8 mo: hypothyroid

Question 23

The placenta has which hormone, that hydrolyzes maternal TG to FFAs for utilization?

Answer 23

Lipoprotein lipase

- FFAs important for fetal fat accretion/neonatal adiposity

Question 24

What id diagnostic for GDM?

Answer 24

at 24-28 weeks:
Give 50 gram oral glucose load

if abnl (>140): give 3 hour 100gm OGTT

• fasting glucose >92
• 1 hr glucose >180
• in T2D: fasting glucose > 95, and 1 hr glucose is >180
• women at higher risk should be screen at first prenatal visit

Question 25

Risks for getting GDM

Answer 25

1. obesity
2. Personal hx of GDM or prev macrosomic infant
3. Fam hx of diabetes in first degree relative
4. PCOS
5. High risk ethnic group
6. Glycosuria

Question 26

The fetus is dependent on maternal thyroid hormon until when?

Answer 26

18 weeks

then it has its own that can be affected that transplacental transfer of maternal antibodies and antithyroid medication

Question 27

Most common cause of hyper and hypothyroidism

Answer 27

Hyper: graves disease

Hypo: hasimotos
in developed country, iodine deficiency in developing

Question 28

Graves disease presentation in pregnancy

Answer 28

Exacerbation in first trimester and postpartum

Improvement in 2nd and 3rd trimester as a result of declining TSH receptor antibodies which are stimulating thyroid stimulating immunoglobulin (TSI)

Question 29

Women with hyperthyroidism have what risk for developing preeclampsia?

Answer 29

5 fold greater

Question 30

Hyperthyroidism has an increased risk of what during pregnancy?

Answer 30

1. severe preeclampsia
2. low birth weight
3. prematurity
4. placental abruption (directly related to maternal T4)

Question 31

Dosing of antithyroid drugs

Answer 31

min dose to titrate TT4 to HIGH nl range for pregnancy (50% above the non-preg range)

or Free T4 at the upper limit of nl

Question 32

Postpartum thyroiditis (PPT)

Answer 32

occurence of hyper or hypothyroidism or both w/in the first year postpartum from autoimmune thyroid dysfxn not prev recog. b4 pregnancy

• hyperthyroid state followed by hypo
• caused by rebound in thyroid autoimmunity postpartum