THYROID DISEASES IN PREGNANCY BY DR SHASHWAT JANI

1. Thyroid Disorders
In
Pregnancy
Dr. Shashwat Jani.
M. S. ( Obs – Gyn ) , F.I.A.O.G.
Diploma in Advance Laparoscopy.
Consultant Assistant Professor,
Smt. N.H.L. Municipal Medical College.
Sheth V. S. General Hospital , Ahmedabad.
Mobile : 99099 44160.
E-mail : drshashwatjani@gmail.com

2. Sources

3.  Thyroid hormones are essential in the
regulation of early development and play a key
role in the maintenance of a normal pregnancy
and in the development of the fetus,
particularly the foetal brain.
 An awareness of the gestational changes
to thyroid physiology and the impact of thyroid
disease on pregnancy and newborns is crucial
for the successful management of
hypothyroidism and hyperthyroidism.
15-Jan-20
Dr Shashwat Jani.
99099 44160.
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4. Important
• Pregnancy is a state of relative iodine deficiency.
increased placental uptake and fetal transfer
increased maternal renal clearance
placenta converts T4 to reverse T3
• Normal Iodine requirement :
In Non Preg/ Preg / Lact : 150 / 175 / 200µg
• Estrogen : Rise in Serum TBG
increase in total T4 and T3
free T4 and T3 unchanged
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Dr Shashwat Jani.
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5. Thyroid Physiology In Pregnancy1-4
•
1. Lazarus JH. Br Med Bull. 2010;1-12.
2. Galofre JC, Davies TF. J Womens Health (Larchmt). 2009;18(11):1847-1856.
3. Thyroid disease and pregnancy. http://www.thyroid.org/patients/brochures/Thyroid_Dis_Pregnancy_broch.pdf.
4. Banerjee. JAPI. 2011:32-34.
Increased
thyroid
hormone
production
Increased
oestrogen
Increased TBG
Decreases
free TH
Stimulation of
hypothalamic
pituitary axis
hCG
Increased T4
placental
transport
Increased
glomerular
filtration rate
Stimulates
TSHR
Type III
deiodinase
Increased TH
degradation
5

6. TSH: decreases in first trimester
TSH increases in second
& third trimester
TT3 & TT4 : rise in preg
FT3 & FT4 : less altered
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7. 15-Jan-20
Dr Shashwat Jani.
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8. 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
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Dr Shashwat Jani.
99099 44160.
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9. TFT In Pregnancy
NOT
PREGNANT
I TRIMESTER II TRIMESTER III TRIMESTER
fT4 pmol/L 11 - 23 11 – 22 11 – 19 7 - 15
fT3 pmol/L 4 – 9 4 – 8 4 - 7 3 – 5
TSH mu/L 0 - 4 0 – 1.6 1 – 1.8 7 – 7.3
• Free T4, free T3 and TSH only should be analyzed
• Total T4 and T3 not to be used
• More emphasis on fT4 and fT3 levels
• TSH levels not very accurate in showing thyroid status
15-Jan-20
Dr Shashwat Jani.
99099 44160.
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10. Fetal Thyroid Physiology
 Develops from 5th week .
 Functions by 10 th week (T4 detected in blood)
 Till 12 weeks fetus totally dependent on mother
 Fetal thyroid distinct entity - post 12 weeks
 Association between fetal and maternal hormone levels
 TRH and iodine cross placenta freely
 Less permeable to T3, T4 and TSH
 Iodine deficiency – cretinism in neonates
 Excessive iodine ingestion by mother – fetal iodine
induced hypothyroidism
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Dr Shashwat Jani.
99099 44160.
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11. Screening For
Thyroid Disorders In Pregnancy
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12. 15-Jan-20
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 Past history of thyroid disease or thyroid
lobectomy or postpartum thyroiditis
 TSH > 3 mIU/ L
 Family history of thyroid disease
 Goitre
 Thyroid antibodies (when known)
 Symptoms or clinical signs suggestive of thyroid
under function or over function, including
anaemia, elevated cholesterol and hyponatraemia
 Type 1 diabetes
 Other autoimmune disorders
 Infertility
 Previous therapeutic head and neck irradiation
 History of miscarriage or preterm delivery
Management of Thyroid Dysfunction during Pregnancy and Postpartum: An Endocrine
Society Clinical Practice Guideline. http://www.endo-
society.org/guidelines/final/upload/Clinical-Guideline-Management-of-Thyroid-Dysfunction-
during-Pregnancy-Postpartum.pdf . Accessed January 27, 2012

13. Study Study Design Sample Size TSH Cut-Off % of patients
missed with
hypothyroidism
in pregnancy
Wang et al Multicenter Cohort
Study
Approx 3000 >4mIU/L 81.6%
Matsuzek et al Case-Control Study 270 >2.5mIU/L 46.4%
Goel et al Prospective Case
Control
1,020 >2.5mIU/L 32%
Vaidya et al Single Centre Case-
Control Study
1,560 >4.2mIU/L 30%
Horacek et al Cross Sectional 400 >3.5mIU/L 55%
• Meta-analysis has shown that case-based screening can miss up to 49 % of
pregnant women with thyroid dysfunction.
• Further support for advocacy of universal screening methods for thyroid disorders
in pregnancy.
Zahra Jouyandeh, Endocrine; 2015
15-Jan-20
Dr Shashwat Jani.
99099 44160.
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14. Results of a Survey answered by 140 Members of the
American Thyroid Association
Dr Shashwat Jani.
99099 44160.
Pavani Srimatkandada,1 Alex Stagnaro-Green,2 and Elizabeth N.
Pearce1
74% advocated
for Universal
Screening.
18% against
universal
screening in
pregnancy.
8% were
unsure.
15-Jan-20

15. Consensus : Indian Guideline on the Management of
Maternal Thyroid disorders
All pregnant females
should be screened at
1st antenatal visit by
measuring TSH levels
(IIa/B).
RV Jayakumar, ITS Guidelines for
Maternal Thyroid Dysfunction , 2012.
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Dr Shashwat Jani.
99099 44160. 15

16. Thyroid Evaluation
In Normal Pregnancy
Recommendation Indication
TSH and FT4
Screening
Interpretation should be trimester specific
TPO-Ab and Tg-Ab Presence of AITD
Ultrasound Advisable when nodular disease is suggested
by clinical examination
Galofre JC, Davies TF. J Womens Health (Larchmt). 2009;18(11):1847-1856.
Usual recommendations for thyroid evaluation in normal pregnancy
16

17. Thyroid Function Tests In Pregnancy
Reference range
used for nonpregnant
population
First trimester Second trimester Third trimester
FT4 (pmol/L)
9–26
(0.7–2.02 ng/dL)
10–16
(0.78–1.25 ng/dL)
9–15.5
(0.70–1.3 ng/dL)
8–14.5
(0.62–1.13 ng/dL)
FT3 (pmol/L)
2.60–5.7
(0.2–0.44 ng/dL)
3–7
(0.23–0.55 ng/dL)
3–5.5
(0.23–0.43 ng/dL)
2.5–5.5
(0.2–0.43 ng/dL)
TSH (mu/L) 0.3–4.2
0.1–2.5 0.2–3.0
0.3–3.0
1. Banerjee S. Thyroid disorders in pregnancy. In: Sidharth N, Joshi S, eds. JAPI. 2011:32-34.
2. Overview of thyroid disease in pregnancy. Uptodate. http://www.uptodate.com/contents/overview-of-
thyroid-disease-in-pregnancy?source=preview&anchor=H1156384#H13. Accessed February 21, 2012.
Median values of trimester-specific thyroid hormones (rounded to nearest 0.5)
17

18. Recommendations From Guidelines On
Upper TSH Limit During Pregnancy
Guidelines Country of
Origin
Trimester specific Ref ranges recommended
ITS
Guidelines
India 1st : 2.5 mIU/L
2nd : 3.0mIU/L
3rd : 3.0 mIU/L
ETA
Guidelines
European 1st : 2.5 mIU/L
2nd : 3.0mIU/L
3rd : 3.0 mIU/L
ATA
Guidelines
American • Use locally derived Ref ranges from a specified
Pregnant population
• If not available use locally derived ref ranges from a
similar population from another country
• If the above is also not available use and upper TSH
ref limit of 4 .0 mIU/L

19. ⚫ Due to heterogenicity in study methodology, ethnic
differences and geographical variations in populations, there is
need for a nationwide study. Until then, it is recommended to
follow lower cut off considering potential benefits of Levothyroxine
in comparison with its minimal risk.
⚫ Trimester specific TSH cut off recommended are:
⚫ 1st trimester 2.5 mIU/L;
⚫ 2nd trimester, 3.0 mIU/L;
⚫ 3rd trimester, 3.0 mIU/L.
ITS & FOGSI 2019 Recommendations For The
Management of Thyroid Dysfunction In Pregnancy
ITSCON Bengaluru
2019

20. The Nine Square Game
To evaluate our Thyroid patient
As per the AACE and ITS Guidelines
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Dr Shashwat Jani.
99099 44160.
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21. FREETHYROXINEorFT4
PRIMARY
HYPERTHYROID
NTI or Pt. on
HYROID
HORMONES
SECONDARY
HYPERTHYROID
SUB-CLINICAL
HYPERTHYROID EUTHYROID
SUB-CLINICAL
HYPOTHYROID
SECONDARY
HYPOTHYROID
NON THYROID
ILLNESS - NTI
PRIMARY
HYPOTHYROID
LOW NORMAL HIGH
THYROID STIMULATING HORMONE - TSH
Basic Thyroid Evaluation
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99099 44160.
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22. 15-Jan-20
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2017 ATA guidelines
Monitoring
Euthyroid TAb+ women should have measurement of serum TSH concentration
performed at time of pregnancy confirmation and every 4 weeks through
midpregnancy.
Pregnancy loss
Insufficient evidence to recommend for or against
However, administration of LT4 to TPOAb-positive euthyroid pregnant women with
a prior history of loss may be considered given its potential benefits in comparison
with its minimal risk.
Preterm delivery
Insufficient evidence to recommend for or against treating euthyroid pregnant
women who are thyroid autoantibody positive with LT4 to prevent preterm
delivery.
Thyroid Auto-Antibodies and
Pregnancy Complications

23. HYPERTHYROIDISM HYPOTHYROIDISM
SOLITARY NODULE
/GOITRE
POSTPARTUM
THYROIDITIS
Thyroid Disorders
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Dr Shashwat Jani.
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24. Hyperthyroidism In Pregnancy:
Epidemiology
• Prevalence rate 0.1% to 0.4% 1
• Types:2
– Overt hyperthyroidism
• Low TSH and high T3, T4
• Occurs in two of 1000 pregnancies
• Associated with foetal loss, foetal growth restriction, pre-
eclampsia and preterm delivery
– Mild or subclinical hyperthyroidism
• Suppressed TSH alone
• Occurs in 1.7% of all pregnancies
• Not associated with complications
1. Galofre JC, Davies TF. Autoimmune thyroid disease in pregnancy: a review. J Womens Health (Larchmt). 2009;18(11):1847-1856.
2. Banerjee S. Thyroid disorders in pregnancy. J Assoc Physicians India. 2011 Jan;59 Suppl:32-4. 24

25. Aetiology
• Graves’ disease (85%–90% of all cases)
• Subacute thyroiditis
• Toxic multinodular goitre
• Toxic adenoma
• TSH-dependent thyrotoxicosis
• Exogenous T3 or T4
• Pregnancy-specific associations
– Hyperemesis gravidarum
– Hydatidiform mole1
– hCG-mediated hyperthyroidism2
1. Fantz CR, Dagogo-Jack S, Ladenson JH, Gronowski AM. Thyroid function during pregnancy. Clin Chem. 1999 Dec;45(12):2250-
2258.
2. Nygaard B. Hyperthyroidism in pregnancy. BMJ Clin Evid. 2015 Jan 21;2015. pii:0611.
25

26. Hyperthyroidism :
Clinical Manifestations
Baskin HJ, Cobin RH, Duick DS, et al; American Association of Clinical Endocrinologists. American Association of Clinical Endocrinologists medical
guidelines for clinical practice for the evaluation and treatment of hyperthyroidism and hypothyroidism. Endocr Pract. 2002 Nov-Dec;8(6):457-69.
Nervousness and irritability
Palpitations and tachycardia
Heat intolerance or increased sweating
Tremor
Weight loss or gain
Alterations in appetite
Frequent bowel movements or diarrhoea
Dependent lower-extremity oedema
Exertional intolerance and dyspnoea
26

27. Hyperthyroidism:
Clinical Manifestations
Baskin HJ, Cobin RH, Duick DS, et al; American Association of Clinical Endocrinologists. American Association of Clinical Endocrinologists medical
guidelines for clinical practice for the evaluation and treatment of hyperthyroidism and hypothyroidism. Endocr Pract. 2002 Nov-Dec;8(6):457-69.
Mental disturbances
Sleep disturbances (including insomnia)
Changes in vision, photophobia, eye irritation, diplopia or exophthalmos
Fatigue and muscle weakness
Thyroid enlargement (depending on cause)
Pretibial myxoedema (in patients with Graves’ disease)
27

28. Complications of
Hyperthyroidism in pregnancy1,2
• Congestive heart failure
• Thyroid storm
• Pre-eclampsia
• Spontaneous abortions
• High rates of still births
• Preterm delivery
1. Fantz CR, Dagogo-Jack S, Ladenson JH, Gronowski AM. Thyroid function during pregnancy. Clin Chem. 1999
Dec;45(12):2250-2258.
2. Galofre JC, Davies TF. Autoimmune thyroid disease in pregnancy: a review. J Womens Health (Larchmt). 2009;18(11):1847-
1856.
• Neonatal deaths
• Two- to-threefold increase
in the frequency of low
birth weight infants
• Foetal or neonatal
hyperthyroidism
• Intrauterine growth
retardation
• Congenital malformations
Maternal complications:1,2 Foetal complications:1
28

29. Graves’ disease
• Graves’ disease is the most
common cause of hyperthyroidism
in pregnancy affecting almost 85%
to 90% of cases
• It is caused by thyroid-stimulating
antibodies
• It is difficult to diagnose due to
similar clinical features as
pregnancy
• Presence of goitre, RAbs and
higher levels of thyroid hormones
is helpful
Chan GW, Mandel SJ. Therapy insight: management of Graves' disease during pregnancy. Nat Clin Pract Endocrinol Metab. 2007 Jun;3(6):470-8. 29

30. Clinical Features Suggesting The Possibility Of
Hyperthyroidism Due To Graves' Disease
in A Pregnant Woman
• History
• Prior history of hyperthyroidism or autoimmune thyroid disease
in the patient or her family
• Presence of typical symptoms of hyperthyroidism including
weight loss (or failure to gain weight), palpitations, proximal
muscle weakness or emotional lability
• Ophthalmopathy or pretibial myxoedema
• Thyroid enlargement
• Accentuation of normal symptoms of pregnancy such as heat
intolerance, diaphoresis and fatigue
• Pruritus
Lazarus J. Thyroid Regulation and Dysfunction in the Pregnant Patient. [Updated 2014 Feb 14]. In: De Groot LJ, Beck-Peccoz P, Chrousos G, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com,
Inc.; 2000-. Available from: http://www.ncbi.nlm.nih.gov/books/NBK279059/
30

31. Treatment
• Thionamide –Propylthiouracil 100-600mg/day
• Methimazole (rare embryopathy)10-40mg/dayDrugs
• fT4 better than TSH
• Transient leucopenia – 10% - cessation ?
• Agranulocytosis 1% - discontinue - ? Serial TLC
• Fever, sore throat- discontinue medication, CBC
Monitoring
• Seldom done in pregnancy
• After disorder is medically controlled
Sub total
thyroidectomy
• Contraindicated in pregnancy
• Avoid pregnancy for 6 months after radioablative
therapy – E- IV ; R – C ; R -32
Ablation
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Dr Shashwat Jani.
99099 44160.
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32. Management of Graves' disease:
Antithyroid drugs
• Propylthiouracil (PTU)—first-line drug
– Given at a dose of 300 mg once daily
– Only in first trimester
• Methimazole/Carbimazole
– Associated with congenital anomalies
– Used when PTU contraindicated or adverse effects
– 10 to 30 mg once daily depending on disease severity
Jastrzębska H. Antithyroid drugs. Thyroid Research. 2015;8(Suppl 1):A12. 32

33. Management of Graves' disease:
2017 Guidelines
• PTU is recommended for the treatment of maternal
hyperthyroidism through 16 weeks of pregnancy.
• When shifting from MMI to PTU, a dose ratio of
approximately 1:20 should be used .
(e.g., MMI 5 mg/ d = PTU 100 mg twice daily).
Alexander EK, Pearce EN, Brent GA, et al. 2017 Guidelines of the American Thyroid Association for the Diagnosis and Management of Thyroid Disease During Pregnancy and the Postpartum.
Thyroid. 2017 Mar;27(3):315-389.
33

34. Thyroid storm and Heart Failure
• Acute , life threatening hypermetabolic state
• Rare in pregnancy
Pregnant
thyrotoxic
woman
Minimal
cardiac
reserve
Decompensation is
precipitated by pre
eclampsia,
anemia,sepsis
ICU
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35. Thyroid storm and Heart Failure
1000mg PTU orally
/crushed
200 mg 6 hrly
iodide 1 hr after PTU
NaI 500-1000mg IV
8hrly
Oral SSKI 5 drops 8 hrly
Lugol solution10 drops
orally 8 hrly
Lithium carbonate
300mg 6 hrly
propranol
Dexamethasone 2mg IV
6 hrly for four doses
Blocks peripheral
conversion of T4 to T3
15-Jan-20
Dr Shashwat Jani.
99099 44160.
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36. Fetal Thyrotoxicosis
• Due to placental transfer of TSI in utero if mother
with Graves disease is not receiving treatment.
• Increased levels of maternal TSI.
• Persistent fetal tachycardia > 160bpm.
• Fetal Goitre / thyrotoxicosis by USG
• Periumblical blood sampling
• Treatment - Thioamide treatment: 5 to 10mmg/day
• Main risk of therapy - fetal hypothyroidism
15-Jan-20
Dr Shashwat Jani.
99099 44160.
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37. Hyperthyroidism Pathway
TSH FT4
Low TSH
Normal FT4
Low TSH
Slightly high FT4
Low TSH
High FT4 > 2.5
Normal pregnancy
Repeat if symptoms
persists
TSH receptor antibodies
Mild Hyperthyroid
Observe until 2nd
trimester
Start PTI 100 – 150g 8 hrly
Max 600 gm
Repeat TSH 2 weeks and
2-4 weeks till normalises
Reduce dose to half initial
dose once FT4 normalises
Post delivery restart/
increase dose
Double the dose if disease
recurs. Continue the least
dose till delivery15-Jan-20
Dr Shashwat Jani.
99099 44160.
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38. Hypothyroidism In Pregnancy
Epidemiology
• Most common thyroid disorder in pregnancy is maternal
hypothyroidism1
• In Western countries:2
– Overt hypothyroidism occurs in 0.3% to 0.5% of pregnancies
– Subclinical hypothyroidism occurs in 2% to 3% of pregnancies
• Study conducted in Mumbai for Asian-Indian population:3
– Hypothyroidism in pregnant women is 4.8%
• Sahu et al study, 20094
– Subclinical hypothyroidism among pregnant women is 6.47%
– Overt hypothyroidism is 4.58%
– Progression from subclinical hypothyroidism to overt
hypothyroidism was seen in 3% to 29% of women with
autoimmunity
38

39. Hypothyroidism In Pregnancy: Types
Reid SM, Middleton P, Cossich MC, Crowther CA. Interventions for clinical and subclinical hypothyroidism in pregnancy. Cochrane Database Syst Rev. 2010
Jul 7;(7):CD007752.
• Elevated serum TSH and
subnormal FT4
• Symptomatic thyroid hormone
deficiency
Overt
hypothyroidism
• Elevated serum TSH and normal
FT4
• Biochemical thyroid hormone
deficiency
Subclinical
hypothyroidism
39

40. Maternal Hypothyroidism : Aetiology
• Inadequate Rx of a woman with pre-existing hypothyroidism
• Overtreatment of a hyperthyroid woman with antithyroid
medications
• In iodine sufficient areas, the most common cause: Hashimoto’s
thyroiditis, an autoimmune disorder
• Treatment of hyperthyroidism using radioactive ablation or surgery
• Thyroid tumour surgery
• Secondary hypothyroidism of pituitary origin
• Tertiary hypothyroidism of hypothalamic origin
• Sheehan syndrome
40

41. Foetal Hypothyroidism: Aetiology
Foetal hypothyroidism causes:
• Antithyroid drug to mother
• Transplacental passage of TSH-receptor
blocking antibodies
Laurberg P, Nygaard B, Glinoer D, et al. Guidelines for TSH-receptor antibody measurements in pregnancy: results of an evidence-based symposium organized by the
European Thyroid Association. Eur J Endocrinol. 1998 Dec;139(6):584-6.
41

42. Impact Of Untreated
Hypothyroidism In Pregnancy
• Anaemia
• Congestive heart failure
• Antepartum depression
• Eclampsia
• Pre-eclampsia
• Gestational hypertension
• Placental abruption
• Increased chances of caesarean
section, preterm delivery
• Postpartum depression
• Postpartum hypertension
• Lactation problems
• Miscarriage
• Growth restriction
• Increased perinatal
mortality
• Impaired
neuropsychointellectual
development
• IUD
Maternal
Foetal
42

43. Concerns Related To Hypothyroidism In
Pregnancy: Need For Monitoring
• 10% of pregnant women have TPO antibodies and are susceptible to:1
– Subclinical hypothyroidism
– Thyroid dysfunction postpartum
• Postpartum thyroid dysfunction occurs in 5% to 9% of women and 25% to
30% remain hypothyroid1
• Women who are on L-Thyroxine at conception require an increase in the
dose during the pregnancy1
• Undertreated maternal hypothyroidism may also have an adverse impact
on child’s subsequent neuropsychological performance2
• Development of foetal brain is dependent on T4 transportation to the
foetus
43

44. Management Of
Hypothyroidism In Pregnancy

45. Hypothyroidism In Pregnancy
• Patients with hypothyroidism should be treated with L-thyroxine
monotherapy.
• L-thyroxine and L-triiodothyronine combinations should not be
administered to pregnant women or those planning pregnancy
• Maternal serum TSH and total FT4 should be monitored every 4
weeks during the first half of pregnancy and at least once between
26 and 32 weeks gestation and L-thyroxine dosages adjusted as
indicated.
• Patients with hypothyroidism being treated with L-thyroxine
who are pregnant, the goal TSH during the second trimester should
be less than 3 mIU/L and during the third trimester should be less
than 3.5 mIU/L.
Garber JR, Cobin RH, Gharib H, et al; American Association of Clinical Endocrinologists and American Thyroid Association Taskforce on Hypothyroidism in Adults. Clinical
practice guidelines for hypothyroidism in adults: cosponsored by the American Association of Clinical Endocrinologists and the American Thyroid Association. Endocr
Pract. 2012 Nov-Dec;18(6):988-1028.
45

46. Endocrine Society Guidelines:
L-Thyroxine therapy
• Caution is recommended in the interpretation of serum free T4 levels
during pregnancy, each laboratory should establish trimester-specific
reference ranges for pregnant women if using a free T4 assay.
• The nonpregnant total T4 range (5–12 g/dl or 50 –150 nmol/liter)
can be adapted in the second and third trimesters by multiplying this
range by 1.5-fold.
• If TSH concentration is 2.5–10 mIU/liter, a starting levothyroxine
dose of 50 g/d or more is recommended.
• Other thyroid preparations (such as T3) are not recommended.
De Groot L, Abalovich M, Alexander EK, et al. Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline. J
Clin Endocrinol Metab. 2012 Aug;97(8):2543-65.
46

47. Thyroxine treatment for hypothyroidism
in pregnancy
• Preconception: Optimise therapy in patients with
pre-existing disease
• Pregnancy confirmed: Increase dose by 30% to 50%
of preconception dose
• Target levels of TSH:
– < 2.5 mIU/L in the first trimester
– < 3 mIU/L in later pregnancy
• After delivery: Reduce dose to preconception dose
• Assess thyroid function at 6 weeks postpartum
• Higher dose for postablative and postsurgical
hypothyroidism
47

48. Thyroxin Treatment For
Hypothyroidism In Pregnancy
Average increment in L-Thyroxine dosage in women without residual
functional thyroid tissue depends on the initial elevation of serum TSH1
1. De Groot L, Abalovich M, Alexander EK, et al. Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline. J Clin Endocrinol
Metab. 2012 Aug;97(8):2543-65.
2. Negro R, Stagnaro-Green A. Diagnosis and management of subclinical hypothyroidism in pregnancy. BMJ. 2014 Oct 6;349:g4929.
Serum TSH elevation Augmented dose of L-Thyroxine
5–10 mIU/L 25–50 mcg/d
10 and 20 mIU/L 50–75 mcg/d
>20 mIU/L 75–100 mcg/d
First trimester TSH Start L-Thyroxine
2.5–5 mIU/L 50 mcg/d
5.0–8.0 mIU/L 75 mcg/d
>8 mIU/L 100 mcg/d
48

49. TSH FT4
Low TSH
Normal FT4
Goitre High TSH
Normal FT4
Physiological
suppression in 1st
trimester
Rpt. At 8 weeks
Hypothyroidism Pathway
High TSH
LowFT4>2.5
Yes No
Repeat
TSH FT4
at 6 wks
Euthyroid
follow up
Subclinical Hypothyoidism
Check antimicrosomal anti TPO
Positive Negative
Role of post partum
Baby at higher risk of hypothyroidism
Standard FU15-Jan-20 49

50. Management: Indian Thyroid Guidelines
• Hypothyroidism diagnosed before pregnancy
– Adjustment of thyroxine dosage to maintain TSH level ≤2.5
µU/mL
– Increment in thyroxine dosage by 30% to 50% by 4 to 6 weeks of
gestation
• Overt hypothyroidism diagnosed during pregnancy
– Titrating T4 dosage to maintain TSH concentrations <2.5 µU/mL in
the first trimester (or <3 µU/mL in the second and third
trimesters) or to trimester-based range
– Reassessment of thyroid function in 30 to 40 days
• Euthyroid women with thyroid antibodies in early stages of
pregnancy
– Monitoring TSH
• Subclinical hypothyroidism in pregnancy
– T4 replacement 50

51. Postpartum Thyroiditis
• Inflammatory thyroid disorder seen in the first
postpartum year
• Manifestations:
– Transient hyperthyroidism
– Transient hypothyroidism
– Transient hyperthyroidism followed by permanent
hypothyroidism
• Aetiology:
– Reversal of the partial immunosuppression resulting
worsening of the underlying autoimmune thyroiditis
Stagnaro-Green A. Clinical review 152: postpartum thyroiditis. J Clin Endocrinol Metab. 2002;87(9):4042-4047.
51

52. Clinical manifestations
• Palpitations
• Fatigue
• Heat intolerance
• Irritability or nervousness
Stagnaro-Green A. Clinical review 152: postpartum thyroiditis. J Clin Endocrinol Metab. 2002;87(9):4042-4047.
• Impaired concentration
• Carelessness
• Dry skin
• Poor memory
• Depression
• Cold intolerance
• Aches and pains
• Decreased energy
Hyperthyroid PPT: Hypothyroid PPT:
52

53. Postpartum thyroiditis Vs.
Graves’ disease
Feature Hyperthyroid PPT Graves’ disease
Prevalence 4.1% 0.2%
Timing (months postpartum) 2–10 4–12
Thyroid enlargement 0%–40% 90%
Bruit 0% Infrequent
Exophthalmos 0% 10%–25%
TSH receptor antibody 0%–25% 95%
Thyroid peroxidase positivity 80% 75%
Aetiology Autoimmune Autoimmune
Stagnaro-Green A. Clinical review 152: postpartum thyroiditis. J Clin Endocrinol Metab. 2002;87(9):4042-4047.
53

54. Treatment: PPT
• Treatment based on disease severity and
patient-physician decision
• Prescribed beta-blockers for palpitations,
irritability and nervousness
• Antithyroid medication not prescribed
Stagnaro-Green A. Clinical review 152: postpartum thyroiditis. J Clin Endocrinol Metab. 2002;87(9):4042-4047.
54

55. Evaluation Of A Solitary Nodule In Pregnancy
TSH
Normal
USG
Observation
Levothyroxine therapy
FNAC in presence of
Cervical Adenopathy or increase
in nodule size
Abnormal
Workup and Treat
Solid Lesion<2cm
Cystic lesion<4cm
Solid Lesion>2cm
Cystic lesion>4cm
> 24 wks< 24 wks
FNAC
malignant Non
malignant
Surgery
15-Jan-20
Dr Shashwat Jani.
99099 44160.
55

56. Just Remember …
 Highly suspect hypothyroidism
 Growth and pubertal delay
 Unexplained depression
 TSH is the test in Hypothy.
 TSH, FT4 to confirm Dx.
 Nine square magic
15-Jan-20
Dr Shashwat Jani.
99099 44160.
56

57.  All obese patients TSH a must
 For all pregnant -test TSH, FT4
 Postmenopausal 15% Hypothy
 Start low and go slow
 Use Levothyroxine only
 Always on empty stomach
 Thyroxine - avoid empirical use
15-Jan-20
Dr Shashwat Jani.
99099 44160.
57