The thyroid gland is located at the front of your neck. It secretes hormones that regulate prolactin and oxytocin, which are vital in breastfeeding.
Thyroid issues have a range of effects on a woman’s health. When the thyroid is not working properly, it might have an effect on milk production. Thyroid issues and autoimmune diseases are linked as well. To safeguard your baby, your immune system is weakened throughout pregnancy. This is a positive development. You don’t want your body to see your developing baby as a foreign invader! Thyroid issues may arise before or during pregnancy, during the postpartum period, or later in life. They may also develop in conjunction with other medical disorders, making diagnosis and treatment more difficult.
Thyroid illness is detected through blood tests that evaluate thyroid stimulating hormone (TCH), triisdothyrine (T3), and tetra-iodothyronine levels. (thyroxine or T4). It is also advised that iodine levels be checked and corrected if they are not enough. Inform your obstetrician and personal care physician if you have a family history of thyroid disease.
Thyroidism is classified into three types: hyperthyroidism, hypothyroidism, and postpartum thyroid malfunction.
Hypothyroidism (underactive thyroid)
- When TSH levels are high and T3/T4 levels are low, this condition is indicated.
- Symptoms include dry skin, cold sensitivity, “baby blues” and/or sadness, exhaustion, hair loss, lack of energy, forgetfulness, constipation, increased menstruation frequency and flow, and minor thyroid enlargement.
- Most common form is Hashimoto’s disease.
- Thyroid hormone replacement therapy is a frequent therapeutic option, particularly during pregnancy and nursing.
- This may lead to pregnancy-induced hypertension and low birth weight.
- Hypothyroid mothers are at risk of having delayed or inadequate milk supply.
- According to research, there may be a detrimental influence on oxytocin.
Hyperthyroidism (overactive thyroid)
- When the TSH level is low and the T3/T4 level is high, this condition is indicated.
- Symptoms include a racing heart, nervous/anxious feelings, sweating, tremors, muscular cramps, lethargy, tiredness, rundown, weight loss, heat sensitivity, diarrhea, reduced menstruation frequency and flow, and minor thyroid enlargement.
- Most common form is Grave’s disease.
- Because of the higher rates of clearance of T3/T4 levels in blood plasma, pregnancy may cause a moderate variant. Some hyperthyroid moms may see an improvement in their symptoms throughout the second and third trimesters, although symptoms might return after delivery.
- Premature birth, pre-eclampsia, fetal growth restriction, and higher maternal and infant mortality are all risks for hyperthyroid mothers.
- According to research, there may be a deleterious influence on prolactin and oxytocin levels.
- Treatments:
- According to research, propylthiouracil (PTU) is the medicine of choice for a nursing woman in this situation. It is excreted in modest levels in breastmilk and has no effect on the thyroid function of the newborn.
- Methimazole is a viable alternative, but the newborn should be closely observed.
Postpartum thyroid dysfunction
- Four types:
- Postpartum thyroid dysfunction (PPT)
- Postpartum Grave’s disease
- Sheehan’s syndrome (postpartum pituitary infarction) is often connected with significant blood loss during/after delivery.
- Lymphocytic hypophysitis
- Occurs in about 5-7% of all pregnancies.
- Women with type 1 diabetes are three times more likely.
- Women who smoke are at three times the risk.
- Symptoms include cold intolerance, dry skin, a lack of energy, decreased focus, and aches and pains.
- Typically begins with hyperthyroidism and may last several weeks before transitioning to hypothyroidism, which can last many months. This condition is more visible clinically, prompting therapy.
Impact on Breastfeeding
Thyroid problems can create problems with milk production and elimination. Because mothers’ thyroid levels may alter throughout pregnancy and delivery, it is advised that they be tested on a regular basis. Depending on the medicine, your baby’s levels may need to be tested on a frequent basis after birth.
Suggested management to support breastfeeding
- In the first year, patients should see their doctor on a regular basis and be tested for hypothyroidism.
- Important to work on improving milk removal.
- Pitocine/oxytocin nasal spray – this may supply the additional hormone required for milk ejection.
- Massage the breast from the outer reaches toward the nipple to make more milk accessible.
- Breast compressions during feedings may assist drive milk from the breast by manually boosting internal pressures.
- Galactagogues are only appropriate as a supportive therapy if milk can be discontinued and thyroid levels are in equilibrium.
- If at all possible, postpone any radioactive tests or treatments until you are no longer nursing. If a scan with a radioactive substance is required, request that it be done using the radioactive material with the shortest half-life, resulting in the shortest interruption of breastfeeding.
- Because contrast dye is not absorbed, you may continue nursing immediately after a scan with it.
Breastfeeding Reminders
- Observe the cues of effective feeding:
- Adequate output.
- Hearing swallows.
- Breasts are fuller before feeding and softening thereafter.
- Examine the baby’s weight increase to ensure that it is steady over the first year.
- Continue to take any thyroid meds as directed.
- Thyroid levels should be checked on a regular basis to ensure that they remain in the upper portion of the normal range.
- Inform all doctors engaged in your care about your treatment and urge them to work together to coordinate care.
Resources
American College of Radiology, Contrast Media Manual, pp.102-103.
https://www.acr.org/-/media/ACR/Files/Clinical-Resources/Contrast_Media.pdf, accessed Mar 15, 2018
Hale,Thomas. https://www.infantrisk.com/
Lawrence, R.A., and Lawrence, R.B. Breastfeeding: A Medical Professional’s Guide, 7th edition, Maryland Heights, MO, 2011, and 8th ed. Elsevier, Philadelphia, PA, 2016.
Breastfeeding Answers: A Guide for Helping Families, 2nd Edition, Mohrbacher N. 2020, Arlington Heights, IL: Nancy Mohrbacher Services.
Breastfeeding and Human Lactation, 6th edition, Wambach K and Spencer B. Jones & Bartlett Learning, Burlington, Massachusetts, 2021.
N. Momotani, R. Yamashita, et al. Thyroid function in breast-fed newborns whose moms are receiving large dosages of propylthiouracil. Endocrinology Clinics (Oxf). 2000 Aug;53(2):177-81. retrieved on March 15, 2018.
Speller, E., Brodribb, W 2012, Breastfeeding and Thyroid disease: A literature review, Breastfeeding Review 20(2),41-47. https://www.ncbi.nlm.nih.gov/pubmed/22946151