The thyroid gland is practically a hormone factory in the throat. This small gland secretes the thyroid hormones T4 and T3 into the circulation, which influence numerous metabolic processes in our bodies: disorders in the thyroid function can lead to an irregular monthly cycle, reduced fertility, increased abortion risk and impaired mental and physical development of the fetuses. Different diseases can lead to hyper/hypo activity of the thyroid gland.
The thyroid gland is controlled by the thyroid stimulating hormone (TSH), which is secreted by the pituitary gland into the blood. At the first sign of hypoactivity, the levels of TSH increase, and conversely, they decrease at the onset of hyperactivity. The function of the thyroid gland is monitored by the levels of TSH and free thyroid hormones.
In order to diagnose an underlying disease further tests are usually needed (estimation of the thyroid gland antibodies, ultrasound, etc.)
The thyroid gland and conception
Women during their fertile years should have TSH levels under 2.5 µU/ml so that in case of a possible pregnancy the supply of thyroid hormones to the embryo is ensured within the first few weeks. Women with problems conceiving should strive for low TSH Levels.
The first sign of thyroid gland hyperactivity is a lowered TSH level in the blood. TSH levels lower than 0.4 µU/ml (which are not caused by an ongoing thyroid hormone therapy), make a further examination of the thyroid gland absolutely necessary.
- Previous tests have shown multiple instances of TSH > 2.0 µU/ml, or an increase in the TRH test greater than 20 µl/ml
- Elevated levels of thyroid gland antibodies
- Current or previous thyroid gland disease resp. operation
- Condition after taking thyroid gland medication
- Type 1 diabetes or other autoimmune diseases
- The individual underwent irradiation of the head or the neck
- The individual had multiple abortions
Thyroid hormone therapy
- Thyroid hormone pills should be taken in the morning, at least 30 minutes before eating.
- At least six weeks are necessary before the regulation cycle between the thyroid gland and TSH levels is set. The TSH levels are only reliable after the thyroid hormone pills have been taken for at least 6 weeks at a constant dosage.
- If a pregnancy occurs intake of the thyroid hormone pills must continue. The dosage must also be checked regularly. The first check of the thyroid gland function has to be performed no later than the 8th pregnancy week.
The thyroid gland and pregnancy
Different factors influence the thyroid gland function after pregnancy has begun: the pregnancy hormone Beta-HCG has an effect on the maternal thyroid gland as well. Therefore, borderline thyroid hyperactivity ensues in early pregnancy (most pronounced in the 10th pregnancy week). If this continues, the probability of an abortion increases. In the case of thyroid hormone intake many patients need increased doses in the first third of the pregnancy.
We recommend a check of the thyroid gland function around the 8th pregnancy week (TSH, free T4) to our patients with thyroid gland disorders. The intervals for further checks are set according to the individual results.
To all our patients without a known thyroid gland disorder we recommend a check of the thyroid gland function around the 10th pregnancy week. (TSH, TPO-antibodies). With the following results no further check-ups of the thyroid gland are necessary: throughout the pregnancy: TSH 0.2-0.5 µU/ml and TPO antibodies negative. Should the results state otherwise, we recommend further thyroid gland testing during the pregnancy.
In the framework of hormonal adjustments after birth, measurable thyroid gland hyperactivity can occur, which over the course of several weeks or months can transform into a treatment-requiring hypoactivity. To our patients with a thyroid gland disease we recommend a check of the TSH level three and six months after giving birth or as recommended by your treating thyroid gland specialist.