This document discusses several autoimmune and endocrine conditions that can affect pregnancy, including their presentation, diagnosis, and management. It covers thyroid disease, rheumatoid arthritis, immune thrombocytopenic purpura, myasthenia gravis, and systemic lupus erythematosus. For each condition, it describes associated risks for the mother and fetus, as well as recommendations for treatment and monitoring during pregnancy and delivery. The goal is to maintain maternal and fetal health while minimizing medication exposure for the baby.
2. Physiologic Changes in Thyroid
Function During Pregnancy
Thyroid binding globulin (TBG) increases
due to reduced hepatic clearance and
estrogenic stimulation of TBG synthesis
The test results that change in pregnancy
are influenced by changes in TBG
concentration
Plasma iodide levels decrease due to fetal
iodide use and increased maternal
clearance -> leads to notable increase in
gland size in 15% of women (without
abnormal TFTs)
3. Physiologic Changes in Thyroid
Function During Pregnancy
Maternal
Status
TSH
**initial
screening
test**
Free T4 Free
Thyroxine
Index
(FTI)
Total T4 Total T3 Resin
Triiodo-
thyronine
Uptake
(RT3U)
Pregnancy No
change
No
change
No
change
Increase Increase Decrease
Hyperthyroidism Decrease Increase Increase Increase Increase
or no
change
Increase
Hypothyroidism Increase Decrease Decrease Decrease Decrease
or no
change
Decrease
4. The Fetal Thyroid
Begins concentrating iodine at 10-
12 weeks
Controlled by pituitary TSH by
approximately 20 weeks
5. Hyperthyroidism
Occurs in 0.2% of
pregnancies; Graves’
disease accounts for
95% of cases
Look for:
-Nervousness
-Tremor
-Tachycardia
-Frequent stools
-Sweating
-Heat intolerance
-Weight loss
-Goiter
-Insomnia
-Palpitations
-Hypertension
-Lid lag/lid retraction
-Pretibial myxedema
6. Fetal & Neonatal Effects of
Hyperthyroidism
Associated with preterm delivery, low
birth weight, fetal loss
Fetal thyrotoxicosis (related to disease
itself or treatment)
Risk of immune-mediated
hypo/hyperthyroidism (due to antibodies
crossing the placenta, esp. in Graves or
chronic autoimmune thyroiditis)
Antibodies in Graves’ disease can be either
stimulatory or inhibitory
Neonates of women with Graves’ who have
been surgically/radioactively treated are at
higher risk, b/c not taking suppression
7. Causes & Diagnosis of
Hyperthyroidism
Most common cause of hyperthyroidism is
Graves’ disease
Document elevated FT4 or elevated FTI with
suppressed TSH, in absence of goiter/mass
Most patients have antibodies to TSH receptor,
antimicrosomal, or antithyroid peroxidase
antibodies, but measurement of these is not
required (though some endocrinologists
recommend measuring TSI, which are
stimulatory antibodies to TSH receptor)
Other causes:
Excess TSH production, gestational
trophoplastic disease, hyperfunctioning thyroid
adenoma, toxic goiter, subacute thyroiditis,
extrathyroid source of TH
8. Treatment of Hyperthyroidism
Goal is to maintain FT4/FTI in high normal
range using lowest possible dose
(minimize fetal exposure)
Measure FT4/FTI q2-4 weeks and titrate
Thioamides (PTU/methimazole) ->
decrease thyroid hormone synthesis by
blocking organification of iodide
PTU also reduces T4->T3 and may work more
quickly
PTU traditionally preferred (older studies found
that methimazole crossed placenta more
readily and was associated with fetal aplasia
cutis; newer studies refute this)
9. Treatment of Hyperthyroidism
Effect of treatment on fetal thyroid
function:
Possible transient suppression of thyroid
function
Fetal goiter associated with Graves’ (usually
drug-induced fetal hypothyroidism)
Fetal thyrotoxicosis due to maternal antibodies
is rare -> screen for growth and normal FHR
Neonate at risk for thyroid dysfunction; notify
pediatrician
Breastfeeding safe when taking
PTU/methimazole
10. Treatment of Hyperthyroidism
Beta-blockers can be used for
symptomatic relief (usually Propanolol)
Reserve thyroidectomy for women in
whom thioamide treatment unsuccessful
Iodine 131 contraindicated (risk of fetal
thyroid ablation especially if exposed after
10 weeks); avoid
pregnancy/breastfeeding for 4 months
after radioactive ablation
11. Hypothyroidism
Symptoms: fatigue, constipation, cold
intolerance, muscle cramps, hair loss, dry
skin, slow reflexes, weight gain,
intellectual slowness, voice changes,
insomnia
Can progress to myxedema and coma
Subclinical hypothyroidism: elevated TSH,
normal FTI in asymptomatic patient
Associated with other autoimmune
disorders
Type 1 DM -> 5-8% risk of hypothyroidism;
25% postpartum thyroid dysfunction
13. Causes & Diagnosis of
Hypothyroidism
Causes:
Hashimoto’s (chronic thyroiditis; most common
in developed countries) & iodine deficiency ->
both associated with goiter
Subacute thyroiditis -> not associated with
goiter
Thyroidectomy, radioactive iodine treatment
Iodine deficiency (most common worldwide;
rare in US)
14. Treatment of Hypothyroidism
Treat with Levothyroxine in
sufficient dose to return TSH to
normal
Adjust dosage every 4 weeks
Check TSH every trimester
15. ACOG Recommendations
Screening of all pregnant women
with a personal history, physical
examination, or symptoms of a
thyroid disorder.
17. Rheumatoid Arthritis in Pregnancy
Affects 1-2% of the general population
More common in women
RA in pregnancy is a common challenge
Sex hormones have effects on disease
activity
70-80% of cases improve during pregnancy
Post-partum flare common
18. Minimal effects on fetal morbidity and
mortality
Steroids may increase risk of IUGR and
PPROM
Active disease correlates with lower
birth
weights
Effect of Pregnancy on RA
19. Avoid NSAIDS and high dose aspirin
Low-dose aspirin safe
Use lowest doses of prednisone
Sulfasalazine, hydroxychloroquine in
refractory cases
Treatment of RA in Pregnancy
22. Immune thrombocytopenic purpura
(ITP)
is a clinical syndrome in which a decreased
number of circulating platelets
(thrombocytopenia) manifests as a
bleeding tendency,
easy bruising (purpura), or extravasation of blood
from capillaries into skin and mucous membranes
(petechiae). Although most cases of acute ITP,
particularly in children, are mild and self-limited,
intracranial hemorrhage may occur when the
platelet count drops below 10 × 109/L (< 10 ×
103/µL);[1] this occurs in 0.5-1% of children, and
half of these cases are fatal.[2]
23. Isolated thrombocytopenia
No drugs or other conditions that
may
affect platelet count
Exclude HIV, Hep C, SLE
ITP – Diagnostic Criteria:
24. Increased platelet destruction
Inhibition of platelet production at
megakaryocyte level
Mediated by IgG Abs against platelet
membrane glycoproteins
Usually a chronic condition
ITP – Pathology:
26. May affect fetus in up to 15% of cases
Neonatal count may drop sharply several days after
birth
Difficult to differentiate from gestational
thrombocytopenia
Epidurals safe if count > 50000
Prednisone +/- IVIG if count < 50000
Manage delivery according to standard obstetric
practice
Avoid NSAIDS post-partum
ITP and Pregnancy
27. Incidence about 5%
Occurs late in pregnancy
Mild (>70 000)
No fetal neonatal
thrombocytopenia
Postpartum resolution
Gestational Thrombocytopenia
29. Typically presents with fluctuating skeletal
muscular weakness
May be ocular or generalised
May have antibodies to the AChR
10-15% have a thymoma
Respiratory muscle involvement may lead
to respiratory failure
Myasthenia Gravis:
30. Pregnancy has a variable effect on the
course of MG
Post-partum exacerbations in 30%
Infections can trigger exacerbations
Steroids can cause transient worsening
MgSO4 is contraindicated
Myasthenia Gravis in Pregnancy:
31. Transplacental passage of IgG anti-AChR
Neuromuscular junction disorders
Transient neonatal MG in 10-20%
Decreased FM’s and breathing
Polyhydramnios
Arthrogryposis multiplex congenita
Myasthenia Gravis – Effect on the Fetus
32. First stage of labour not affected
Second stage: expulsive efforts may
weaken
Assisted vaginal delivery may be indicated
Pre-labour anaesthetic assessment
indicated
Myasthenia Gravis – Labour & Delivery
34. Severe pulmonary hypertension
Restrictive lung disease
Heart failure
History of severe HELLP or PET
Stroke within previous 6/12
Lupus flare within previous 6/12
SLE features associated with high maternal and fetal risks –
pregnancy relatively contraindicated
36. Occurs in up to 2% of mothers with SLE
Targets skin and cardiac tissue,rarely other tissues
Congenital partial or complete heart block
Heart block detected in utero
Complete heart block: PNM of 44%
Rash: erythematous annular lesions
Rash clears within 6/12
Maternal dexamethasone may prevent progression
of heart block
Neonatal pacemaker if HR<55
Neonatal Lupus: