Pregnancy and an underactive thyroid may lead to complications if not managed. It can contribute to symptoms like fatigue, weight changes, and menstrual irregularities, which might affect the chances of conception.
It also poses a risk of miscarriage. It can be helpful to stay in regular contact with your healthcare team and monitor both your hormone and thyroid levels throughout pregnancy.
Hypothyroidism: An Overview
Hypothyroidism is caused by an underactive thyroid, which means the thyroid doesn't produce enough hormones. This slows down your metabolism and can make you feel tired or cause weight gain, especially during pregnancy.Though hypothyroidism is manageable, it is important to address it early to reduce the risk of complications such as preterm birth, developmental delays, and even stillbirth. Fortunately, with regular monitoring and appropriate treatment, most individuals with hypothyroidism can have a healthy pregnancy.
Role of thyroid hormone in pregnancy
As the pregnancy progresses into the second trimester, the baby’s thyroid becomes functional, but maternal thyroid hormones continue to play an essential role in maintaining a healthy pregnancy.
Adequate levels of thyroid hormone support normal foetal growth, brain development, and metabolic functions. For the mother, thyroid hormones also help maintain metabolic stability and ensure that energy levels remain balanced throughout pregnancy.
Types of Hypothyroidism
There are several types of hypothyroidism, and recognising them is vital for proper diagnosis and treatment.Primary hypothyroidism
This condition often leads to high levels of thyroid-stimulating hormone (TSH) as the body attempts to compensate for the low hormone levels. Primary hypothyroidism can be caused by conditions like Hashimoto’s disease, thyroid surgery, or radiation therapy.
Secondary hypothyroidism
Tertiary hypothyroidism
This, in turn, prevents the pituitary gland from releasing sufficient TSH, thereby impacting thyroid function. This condition is also rare and often referred to as central hypothyroidism.
Subclinical hypothyroidism
During pregnancy, this condition should be monitored closely, as it can worsen. Treatment may be recommended if TSH levels rise significantly or if signs of autoimmune thyroid disease are present, such as TPO antibodies.
TPO antibodies are markers that can indicate an autoimmune attack on the thyroid gland, potentially worsening thyroid function. Regular monitoring and early intervention can help manage the condition and support both maternal and foetal health.
Symptoms of Hypothyroidism
Since there are different types of hypothyroidism, each of them can trigger different, yet subtle symptoms. These symptoms can often appear to be the same as other symptoms. Some of the common symptoms of hypothyroidism are as follows:- Low cold tolerance
- Dry skin
- Unexpected weight gain
- Tiredness/lethargy
- Slow heart rate
- Depression
- Thinning hair
Doctors recommend a blood test to rule out hypothyroidism, as some of its symptoms can be similar to those of a normal pregnancy. This helps ensure you receive the appropriate care and support.
Diagnosis of Hypothyroidism
Thyroid function testing includes Free T4, TSH and thyroid antibody tests to determine foetal and maternal well-being. Early diagnosis of hypothyroidism is important for pregnant women to prevent the risk of preterm birth, increased risk of miscarriage and foetal neurodevelopmental problems.The usual trimester-specific range is as follows:
- 1st Trimester (0–13 weeks): TSH: 0.1 to 2.5 mIU/L
- 2nd Trimester (14–26 weeks): TSH: 0.2 to 3.0 mIU/L
- 3rd Trimester (27–40 weeks): TSH: 0.3 to 3.0 mIU/L
Treatment of Hypothyroidism
Primary Treatment
Purpose of Medication
Monitoring and Dosage
Iodine Intake
Medication Timing
It is recommended to undergo TPO antibody testing, especially if you have had subclinical hypothyroidism or are at risk for miscarriage.
How Does Thyroid Affect Pregnancy?
Low thyroid levels can affect women in numerous ways. Some of the ways it affects across different stages are as follows:Pre-pregnancy
Hypothyroidism may be linked to conditions such as ovarian cysts, elevated thyroid peroxidase antibodies, or lower basal body temperature. These factors might make it harder to conceive or could affect early pregnancy, but with proper management, many people go on to have healthy pregnancies.
If you have a family history of thyroid issues, it is extremely important to monitor them regularly. If it is not diagnosed promptly, there may be complications such as placental abruption and foetal neurodevelopmental issues.
It’s important to keep an eye out for the symptoms of thyroid issues, especially in early pregnancy. As soon as you notice any symptoms, it’s best to consult your doctor and get it treated. This prevents the risk from increasing later.
Pregnancy
Your healthcare professional monitors the results to check that your hormones are at the appropriate level. Your body may also need higher hormone levels to support the baby.
Taking prenatal vitamins can be of great help. However, ensure that these have enough iron and calcium. If required, the doctor may also recommend hormone replacement therapy.
Uncontrolled symptoms of hypothyroidism can, however, be risky. This can have a severe negative impact on the growth and development of a baby's brain. Moreover, it also increases the risk of premature birth, maternal anaemia, miscarriage or an increase in maternal blood pressure.
Post-pregnancy
The symptoms of postpartum thyroiditis vary from woman to woman. However, it is extremely important to note how your body is reacting in the early stages. If you have hypothyroidism, it can also affect your body's capacity to produce milk.
Therefore, in that case, you might have to undergo proper hormone replacement therapy to solve the problem. Around 15-20% of women who have postpartum thyroiditis end up developing permanent hypothyroidism.
Possible Signs of Thyroid Dysfunction During Pregnancy
If you are concerned about thyroid function during pregnancy, being aware of certain changes in your body may be helpful. Some signs that could suggest an imbalance include:- Weight gain
- Extreme fatigue
- Skin and hair colour change
- Hoarse voice
- Palpitations
What Causes Thyroid Diseases During Pregnancy?
Hashimoto's Disease is a common condition that can affect thyroid function during pregnancy. This autoimmune disease causes the immune system to attack the thyroid gland, which can reduce thyroid hormone production. As a result, symptoms such as joint stiffness, constipation, sensitivity to cold, and muscle weakness may occur during pregnancy.Maintaining Thyroid Health During Pregnancy
Whether you have a pre-existing thyroid condition or not, you need to be mindful of your thyroid health during pregnancy. The arising complications can make it difficult for your child. Therefore, here are a few tips on maintaining thyroid health during pregnancy:Regular prenatal checkups
Proper exercise
Avoid excessive iodine intake
Stress management
Risks of Untreated Hypothyroidism
If proper diagnosis is done on time, a lot of women can have a healthy pregnancy despite hypothyroidism. However, if hypothyroidism isn't treated on time, it can cause a lot of other complications for the mother, such as the following:- Preeclampsia
- Anaemia
- Miscarriage
- Placental abruption
- Postpartum haemorrhage
Hypothyroidism affects the child’s health in numerous ways, such as the following:
- Preterm birth
- Stillbirth
- Developmental delays
- Congenital hypothyroidism
- Low birth weight
Postpartum Considerations
After you give birth, your thyroid medication may need to return to your pre-pregnancy dosage. It's important to check your thyroid levels to ensure the medication remains right for you. Factors such as the type of thyroid condition, its severity, and whether you're breastfeeding can all influence your dosage needs.Postpartum thyroiditis can occur after childbirth, especially if you have a history of Type 1 diabetes, previous thyroiditis, or positive thyroid peroxidase antibodies (TPOAb). If this applies to you, it’s important to consult with your healthcare professional. Regular screening of your TSH levels helps monitor your thyroid function.
If you have a history of postpartum thyroiditis, ongoing follow-up is generally recommended to help manage your thyroid health in the long term. It’s best to speak to your healthcare expert for personalised advice based on your specific health history.
Impact of hypothyroidism on breastfeeding
When to seek medical advice?
If you notice any symptoms, it’s important to let your healthcare professional know. They can carry out tests and create the right treatment plan for you. Keeping track of changes in your body and getting them checked early is important for both your health and your baby’s.
With appropriate monitoring and treatment, individuals with hypothyroidism can experience a healthy pregnancy and deliver a healthy baby. Regular thyroid function tests, consistent follow-up with healthcare professionals, and effective management of thyroid hormone levels are essential.
Maintaining optimal thyroid health during pregnancy is vital not only for your overall well-being and energy levels but also for the healthy development of your baby. It is important to consult with your healthcare expert for personalised guidance and recommendations.
FAQs
- Can an underactive thyroid harm pregnancy?
Yes, an underactive thyroid can harm pregnancy. If not treated at the right time, it can increase the risk of pregnancy and preterm birth. - Can an underactive thyroid make it hard to get pregnant?
Yes, an underactive thyroid can make it difficult to get pregnant. It is advisable to consult your healthcare professional.
