1. Thyroid Disease in pregnancy

2. Introduction
A number of thyroid disorder are common in the general population.
The interaction between pregnancy and thyroid gland is fascinating;
There are fundamental changes in term of tests,
Intimate relationship between maternal and fetal thyroid function,
The drug that affect the mother thyroid can also affect the fetal
A number of interaction , abnormal pregnancy and thyroid conditions??

3. Introduction
Endocrine disorders are increasingly encountered in pregnancy
To optimize pregnancy outcome, it is essential to understand the physiology underlying these conditions.
To know which investigations to use and what kind of treatment is safe in pregnancy.
What is the most common endocrine disorder in women of childbearing?
What is the second most common?

4. Fetal Thyroid 7-9 weeks formation of thyroid gland
10 weeks TSH and Thyroxine deteable
17 weeks maturation of the gland
>18weeks response to TSH stimulation

5. Thyroid disease in pregnancy
Hypothrodism
Hyperthroidism
Gestational Thrytoxicosis
Thyrodities
Thyroid storm
Thyroid nodule
Thyroid cancer

6. Thyroid dysfunction Hyperthyrodism
Frequently encountered
Usually diagnosed prior to pregnancy
Symptoms of hyperthroidism are similar to pregnancy changes;
Delaying initiation or optimizing treatment.
Appropriate ante-natal management, requires ??

7. Physiological changes
Thyroid stimulating hormone (TSH)
Human chorionic Gonadotrophin (hCG)
What similarity between TSH& hCG??
What mimics thyrotoxicosis??
Changes in pregnancy;
TSH is suppressed
thyroid binding globulin
Total &Free T3 &T4,
Renal clearance of Iodine
Thyroid hormone and the placenta

8. Hyperthyroidism Incidence; 1:500 Majority prior to pregnancy
90-95% due to Grave's disease
autoimmune
thyroid stimulating antibodies against TSH receptors
Other causes of thyrotoxicosis;
toxic nodule
multiple thyroid nodule
Gestational trophoplatic tumour

9. Grave’s Disease Antibodies, cross the placenta and lead to??
Abortion, Intrauterine growth restriction (IUGR)
still birth, fetal tachycardia, premature labour( Fetal loss)
Uncontrolled hyperthyroidism
Cardiac arrhythmia, Arterial fibrillation Diarrhea, vomiting, abdominal pain and Psychosis.

10. Diagnosis Symptoms, increase heart rate
heat intolerance
weight loss
heart murmur
Investigation, TSH,T4&T3,
Diagnosis difficult in pregnancy, reason??

11. Management Medication, to stop synthesis of thyroid hormone
Untreated, leads to fetal loss
Drugs used to maintainT4&T3 to a high /normal range.
Radioactive Iodine, contraindicated in pregnancy,
effect fetal gland
Medication, to stop synthesis of thyroid hormone
1) Thioamide; carbimazole 10-40mg( methiazole, aplastic cutis, embryopathy)
Start with lower does
Large does cross placenta; fetal hypothroidism
10% aplastic leukopenia
2) Thiourea; propylethiouracil mg( convertT4 to T3
cross placenta less readily,
In high doses cause fetal hypothyroidism and goiter
Breast feeding??

12. Hypothrodism Difficulty in conceiving
Majority on thyroxine prior to pregnancy
Incidence is 9/1000 pregnancy
Risks: fetal loss: abortion, still birth, premature labour
In the newborn, congenital cretinism as a result of congenital hypothyroidism

13. Etiology Primary >95% Autoimune thyroditites
Iodine deficiency, over treated hyperthyroid, treatment with radio active Iodine( to avoid this would should one do?
Lithium
Postpatum Haemorrhage Sheehan syndrome

14. Diagnosis and mangement
TSH is ?
T4 is ?
Treatment
Throxine may need to be increased in pregnancy to restore TSH to normal
Treatment , throxine 25, 50, 100 ug
Serial TSH, keep it below normal level

15. Effect of hypothroidism on pregnancy
Thyroid hormone are required for normal mental development.
Fetus, congenital cretinism
Infant, diminished school performance

16. Postparum
Postnatal, thyroid dysfunction(10-20%) and postnatal depression 6-12 weeks after delivery, initially hyper then hypo