Fetus hypothyroidism

Myxedema and goiter are the main conditions for which thyroid preparations are indicated. The treatment of cretinism is difficult because it is recognized only at or after birth. Even if this disease could be diagnosed m utero, thyroid hormones do not readily cross the placental barrier. In addition, the fetus, as does a premature infant, rapidly deactivates the thyroid hormones. The halogen-free analogue DlMlT [26384-44-7] (3), which is resistant to fetal deiodinases, may prove useful for fetal hypothyroidism (cretinism). 

Early worries about risk of cancer or leukaemia have proven unfounded in prolonged follow-up studies. However radioactive treatment is contraindicated in pregnant woman or nursing mothers. Other risks for the fetus are abortion, intrauterine death, congenital malformation and congenital hypothyroidism (if administered after 12 weeks gestation). It is customary to avoid pregnancy for the first... 

The major adverse effect on the fetus is altered thyroid function (SEDA-13, 141 SEDA-14, 149 SEDA-19, 194 SEDA-20, 176). There have been individual reports of neonatal hyperthyroxinemia (79), goiter (80), and hypothyroidism (81). In the patient with goiter there was associated hypotonia, bradycardia, large fontanelles, and macroglossia (80). 

Two neonates who had been given intravenous amiodarone as fetuses at 26 and 29 weeks and whose mothers had also taken it orally developed hypothyroidism (83). The authors suggested that low dietary iodine intake by the mothers may have contributed, by enhancing the Wolff-Chaikoff effect. 

Iodine-induced goiter Iodine-induced hypothyroidism Fetus and neonate... 

Maternal lithium therapy may also endanger the fetus. Neonatal diabetes insipidus, hypothyroidism, cardiac dysfunction, respiratory difficulties, low muscle tone and lethargy have all been reported. Lithium has been shown to equilibrate completely across the placenta, with higher lithium concentrations at delivery associated with more perinatal complications [149]. 

It has been long known that hypothyroidism leads to retardation and other serious developmental disorders. 52 It has been shown that the neuropsychological development of a fetus is adversely affected when thyroid deficiency occurs in a pregnant woman and her fetus. 53 Even very small reductions in thyroid levels in mothers during pregnancy have been shown... 

It has been reported that (CH3CH2CH2CH2)3SnCl exposure in the uterus of rats causes a dramatic increase in low weights of fetuses, due to hypothyroidism in the carrier. Other xenobiotics, such as the RXR agonist bexarotene, have been reported to result in similar symptoms and effects in human patients with lymphoma. ... 

Radiopharmaceutical, to be prepared and administered only by personnel trained in radiopharmaceuticals premedicate with acetaminophen and antihistamines slow infusion rate or interrupt infusion for infusion reactions medications for treatment of hypersensitivity reactions should be available for immediate use avoid in pregnant females may cause hypothyroidism in fetus two-step administration MoAB and low radioisotope dose is followed after 1-2 weeks by MoAB and therapeutic radioisotope dose renally excreted impaired renal function may increase exposure to radioactive components patients must be trained in precautions to decrease radiation exposure to family, friends, and general public... 

Fetus abortion, stillbirth, congenital anomalies, increased perinatal mortality, increased infant mortality, neurological cretinism (mental deficiency, deaf mutism, spastic deplegia, squint), hypothyroid cretinism (mental deficiency), psychomotor defects. 

Long-term therapy is contraindicated, because iodides will cross the placenta and into breast milk, causing hypothyroidism (goiter) in the fetus and neonate. Short, intensive therapy for thyrotoxic crisis may be utilized without adverse effects to the fetus. 

CHRONIC HEALTH RISKS headaches numbness weakness dizziness tremors loss of appetite effects on central nervous system deafness loss of muscle coordination loss of visual acuity respiratory effects cardiovascular effects cretinism enlarged thyroid gland congenital hypothyroidism in newborns malformation in fetus low fetal body weights in animals. 

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