Thyroid and Pregnancy

The hormones of the thyroid gland may present a sudden increase during pregnancy, which is deemed normal and is expected, as a pregnancy is accompanied in general by a … hormonal explosion. In particular, the levels of the so-called total Τ3 and Τ4 are increased. However, there are also changes in the function of the thyroid, which occur during pregnancy, but can be related to a problem that preexisted the pregnancy.

It is therefore good, that an examination of the thyroid hormones is performed at the beginning of the pregnancy.

Symptoms that are related with the thyroid disorder, such as the feeling of fatigue, irritability and tachycardia should not be always related with the symptoms of pregnancy. The control of the thyroid gland and the relative examinations are deemed necessary. If the results of these examinations are normal and there is no history of thyroid disease, a re-examination is not required. However, if the examinations show a problem in the function of the thyroid, treatment is required through medication that will be recommended by the endocrinologist, who will also define how regularly a re-examination of the thyroid hormones will have to be performed. It is important to point out that the thyroid disorder may affect the course of the pregnancy and of the neurological development of the fetus.

Thyroid and Fertility

The thyroid hormones may affect the reproductive capacity. This is due to the fact that thyroxine Τ4 and triiodothyronine Τ3 are necessary for:

  • the proper function of the menstrual cycle in women
  • the normal ovulation
  • the function of the corpus luteum
  • the implantation of the embryo
  • the function of the placenta

More particularly, hyperthyroidism is related with reduction in fertility, as it can cause disorders in the menstrual frequency and in the occurrence of ovulation, as well as affect the implantation of the embryo. Hypothyroidism may also reduce the chances of success of an in vitro fertilization. Treatment is therefore required, so that the thyroid hormones return to their natural levels.

A mild hyperthyroidism seems to affect fertility much less, compared to hypothyroidism. Although it is related with some menstrual disorders, there is no connection between it and the abnormal or irregular ovulation. However, when there are cases of severe hyperthyroidism, the intervention of the endocrinologist must be immediate. When the thyroid hormones are much higher than their natural levels, sudden cessation of the period may be caused, while there seems that there is a connection between severe hyperthyroidism and complications -even miscarriage- during pregnancy.


Hyperparathyroidism is the condition where the parathyroid glands hyperfunction.

The parathyroid glands are located behind the thyroid gland and are almost in contact with it. Most of the people have four parathyroid glands, while a percentage of approximately 20% may have five or six or less than four glands. The parathyroid glands are responsible for the production and secretion of the hormone parathormone. The parathormone contributes to the regulation of calcium and phosphorus levels in our body. When the parathyroid glands are hyperfunctioning, an excess of parathormone is produced.

The hyperparathyroidism disorder seems that it occurs mainly at the age of 50-70 years and can cause serious problems, reducing life expectancy by 5-6 years. The excess of parathormone in the human body is related with the increase of calcium levels in the blood, urine and bones, as well as with the decrease of phosphorus concentration. Calcium and phosphorus play a very important part in the function of the human body.

The hyperparathyroidism is related with problems, such as:

  • Risk of atherosclerotic plaque rupture
  • Skeletal problems
  • Kidney damages
  • Heart failure
  • Depression