Hyperthyroidism, characterized by a TSH level of 8.4 in the 4th week of pregnancy, can pose certain risks and complications. It is essential to monitor thyroid function closely during pregnancy as untreated hyperthyroidism can lead to adverse effects on both the mother and baby. Complications may include an increased risk of miscarriage, preterm birth, low birth weight, preeclampsia, and developmental issues in the baby. It is crucial to consult with a healthcare provider who specializes in managing thyroid disorders during pregnancy for appropriate monitoring and treatment options.