Flashcards in Pregnancy Endocrinology Deck (66):
What major polypeptide hormones are produced by the placenta?
What steroid hormones are produced by the placenta?
Detail the changes in E2, P, and PRL over the course of pregnancy.
Increase over time
What cell in the placenta is predominately responsible for steroid and protein production?
What circulation are most placental hormones secreted into?
When is hCG produced, by what cells?
8 days post fertilization
What effect does hCG have on the corpus luteum?
Maintains corpus luteum
Corpus luteum produces progesterone until week 11 when the placenta takes over
What effect can hCG have on TSH?
What effect can hCG have on thyroid function?
hCG has TSH activity at high levels
What is the most abundent secretory product of the placenta?
What cells secrete hPL?
Is hPGH regulated by GHRH or somatostatin?
What effect does hPGH have on the mother?
Promotes insulin resistance
Why are statins contraindicated in pregnancy?
Cholesterol precursors for steroid synthesis are required
What is the role of progesterone during pregnancy?
Maintains uterine lining
Promotes decidua formation
Maintains uterine quiescence
What is the substrate used by the placenta to make progesterone?
How is the fetus protected from high progesterone levels?
Lacks enzyme needed to convert pregnenolone to progesterone
What effect does progesterone have on a mother regarding cellular immunity?
Improvement of autoimmune processes
Increased susceptibility to intracellular pathogens
What is the precursor for estrogens?
60% fetal DHEAS
40% maternal DHEAS
What effect does estrogen have on coagulability during pregnancy?
What is the leading cause of maternal death?
What happens to total cortisol and TT4 levels during prengnancy?
Increase- E2 increases binding protein synthesis at the liver
A woman develops pancreatitis during pregnancy. The physician believes it is likely hormonaly related. What hormone is responsible?
Estrogen- increased TG synthesis
Why does the pituitary increase in pregnancy?
Estrogen stimulates lactotrophs
An increased pituitary is at risk of what complication?
Sheehan syndrome/postpartum hypopituitarism- ischemic necrosis of pituitary gland due to blood loss and hypovolemic shock during/after birth
What must occur to maternal estrogen levels in order for successful lactation to occur?
Estrogen must fall- decreased competetion with prolactin for prolactin receptor
A woman with RA notices her condition has improved being pregnant. Explain why.
Progesterone- decreases cellular immunity
During pregnany women become resistant to aldosterone and AgII. Why?
Progesterone competes for aldosterone receptor
What medication is a progesterone antagonist that is an abortifacent when given early in gestation?
Traditionally, what hormone has been identified as the placental hormone responsible for the development of maternal insulin resistance?
In the late second and third trimester women manifest a nearly 50% decrease in insulin mediated glucose disposal. What effect does this have on maternal insulin production?
Glucose transport to the fetus occurs via what placental glucose transporter?
When is fetal insulin secreted?
Response to maternal glucose
How quickly does insulin sensitivity return post partum?
Gestational diabetes is caused by abnormalities in at least 3 aspects of fuel metabolism what are these aspects?
Impaired insulin secretion
Increased hepatic glucose production
(most women overweight, think unmasking of DM2)
Detail the normal fasting plasma glucose in a normal pregnancy.
~10 mg/dl lower than non-pregnant individuals
Presumably due to increase in glucose uptake by fetoplacental unit
What effect does hyperglycemia have on fetal insulin production?
Beta cell hyperplasia
What effect does hyperglycemia/hyperinsulinemia have on fetal growth?
A 26-year-old G1P0 diabetic woman is delivering at 42 weeks' gestation has a complicated vaginal delivery in which the shoulders do not deliver with ease. The birth weight is 4300 grams. The baby is noted postpartum to have difficulty moving the left arm. What complication has likely occured?
What populations are at highest risk for GDM?
Fetal birth weight >4000 g
DM1 and DM2 can result in malformations of the heart or spine. Why are these complications not scene in women who develop GDM?
Glucose is teratogen in first trimester
Women with GDM should not have elevated glucose in first trimester
What are maternal complications that can arise from GDM?
Increased incidence of preeclampsia
Preterm labor due to polyhdramnios
40-50% risk of developing DM2 in 10-20 years (most important complication)
What is standard practice for GDM screening?
50 g oral glucose test at 24-28 weeks
If abnormal (>130-140) give a diagnostic 3 hour 100 g OGTT
2 abnormal values on OGTT are diagnostic
What are risk factors for GDM?
DM in first degree relative
Hx of macrosomic infant
Hx of GDM
Hx of PCOS
When should women with risk factors for GDM be screened?
First prenatal visit
Detail the therapy for a woman diagnosed with GDM.
Carbohydrate, fat, calorie restricted diet
Check blood glucose throughout the day
If therapy or the fetus is showing abnormal growth in a woman with GDM what is the next course of action?
Insulin or glyburide
What hypoglycemic agent crosses the placenta least well?
How do maternal iodine requirements change during pregnancy?
Women who are unable to meet increased demand become increasingly hypothyroid and develop a goiter
What conditions lead to increased hCG and can result in gestational thyrotoxicosis.
What is the leading cause of hypothroidism globally and in the US?
Globally- iodine deficiency
US- hasimoto thyroiditis
Why should T3 not be used in pregnant women for replacement of thyroid hormone?
Fetal brain has mainly T4 receptors
What components of fetal brain development are dependent on T4?
What women should be screened for thyroid disease? When?
Women with risk factors:
Hx of thyroid disease
First prenatal visit
Does subclinical hyperthyroidism cause adverse pregnancy outcomes?
A pregnant woman has suppressed TSH, what test can not be done to differentiate the cause of thyrotoxicosis?
Does gestational hyperthyroidism need to be treated with antithyroid medication?
Should TSH be used to titrate antithyroid therapy?
No- can remain suppressed and attempts to normalize it may render the fetus hypothryoid
Define post partum thyroiditis.
Hyperthyroidism, hypothyroidism, or both within the first year postpartum from autoimmune thyroid dysfunction not previously recognized
What types of valvular heart lesions improve with pregnancy, which do worse?
Mitral regurgitation improves
Aortic stenosis/pulmonary HTN do worse
When is TSH normally low?
What is the function of progesterone and pregnenolone in the fetus?
Substrate for fetal aldosterone and cortisol
A woman with DM becomes pregnant, why must her insulin dosing change?
Increased insulin sensitivity
Must decrease insulin
Risk for hypoglycemia
What hormone increases lipolysis and insulin secretion in pregnancy?