Does my thyroid matter? - By Dr. Jessica Scotchie

There are many causes of infertility and recurrent pregnancy loss. Often the tests performed by Tennessee Reprodictive Medicine are screening tests to guide further investigation or treatment. Thyroid dysfunction is one condition that may affect our patients.

The thyroid gland is a small gland located in the neck, responsible for making thyroid hormones which help regulate metabolism. Thyroid dysfunction is very common, affecting up to 10% of the population at any given time. In general there are two forms of dysfunction: decreased thyroid hormone production (hypothyroidism) and increased thyroid hormone production (hyperthyroidism). Underactive disease, or hypothyroidism, affects 2-10% of individuals, and occurs 5-8 times as often in women than men. Overactive disease, or hyperthyroidism, is less common, affecting 1-5% of individuals. With both forms of thyroid disease, women are affected far more commonly than men (5-8x more often).

The symptoms of thyroid disease are easily recognized, but are also commonly seen in other disease presentations and among healthy individuals. Hypothyroidism presents with weight gain, fatigue, cold intolerance, hair loss, constipation, muscle aches, and difficulty concentrating. Hyperthyroidism often presents with weight loss, tremors, hair loss, anxiety, irregular heart beat (palpitations), and sweating. Both underactive and overactive disease can result in menstrual irregularities in women.

Most thyroid diseases are caused by autoantibodies against components of the thyroid gland. Antibodies are molecules made by our immune system to fight infection; in the case of auto-antibodies, our immune systems mistakenly make molecules to fight a part of our body that the immune system should recognize as a normal part of the body. The end result is organ damage, which either causes decreased thyroid hormone production (hypothyroidism) or increased hormone production (hyperthyroidism).

How do we screen for thyroid disease? Physicians will generally start with a thyroid stimulating hormone level (TSH). The TSH hormone is made in the pituitary gland (in the brain) and is sent to the thyroid gland to tell it to make thyroid hormone (think of the accelerator in your car). The thyroid then makes thyroid hormones (T4 and T3) which circulate back to the pituitary gland; the pituitary gland then recognizes that there is sufficient circulating T4 and T3 and keeps the TSH in a normal range (think of a feedback loop). When there is too little thyroid hormone, the pituitary should respond by increasing the TSH level (as if stepping on the accelerator harder to make the car go faster), therefore underactive thyroid disease typically presents with an elevated TSH level. In contrast, if there is too much thyroid hormone, the TSH is usually suppressed, because the high levels of T4 and/or T3 have signaled back to the pituitary that there is no need for TSH to keep signaling for more T4 and T3 to be made (think of the accelerator being pushed as hard as possible, there would be no need for you to push harder to go faster). There are other conditions in which this relationship is not as straightforward as just described, and for this reason it is important to rely on your physician to correctly interpret hormone results.

How do we treat thyroid disease? For the two abnormalities described previously, the goal is to restore the thyroid hormone levels back to normal. For hypothyroid disease, we replete the patient with thyroid hormone. Usually after about 4 weeks of treatment the TSH level is rechecked and the dose adjusted until the TSH is in a normal range. For hyperthyroid disease, treatment options include medications to suppress thyroid production (propylthiouracil and methimazole), radioiodine ablation, and surgical removal of the thyroid. The optimal treatment can be decided with your physician. There are other causes of thyroid diseases (tumors, cancer, nodular goiter) that are treated differently and beyond the scope of this blog.

You may be asking yourself, why does a fertility specialist care about the thyroid? The answer is normal thyroid function is critical for normal menstrual function and for optimal pregnancy outcomes. Hypothyroidism has been associated with increased risks of miscarriage, pre-eclampsia (blood pressure disease in pregnancy), and low birth weight babies. Untreated hypothyroidism can also result in mental deficiencies in children, which in the most severe form is known as cretinism. Some women do not have overt hypothyroidism, but have mild lab abnormalities that we would call subclinical hypothyroidism (high TSH but normal thyroid hormone levels). Subclinical hypothyroidism has also been associated with higher rates of miscarriage.

Hyperthyroidism is also associated with adverse outcomes, including pre-term delivery, pre-eclampsia, maternal heart failure, low birth weight babies, and miscarriage. Fetal hyperthyroidism can also occur as a result of maternal autoantibodies passing through the placenta, and causing fetal goiter (enlarged thyroid) which in severe cases can affect the mode of delivery.

Clearly, avoiding these complications is critical and generally easy to do by closely monitoring a woman’s TSH level and adjusting thyroid medications to keep the TSH level in a low-normal range (ideally < 2.5 mIU/ml in pregnancy). Women with hypothyroidism typically require increased doses of levothyroxine in pregnancy due to the expanding plasma volume that occurs in pregnancy. Women with hyperthyroidism are usually treated with oral medications, as radioiodine cannot be used during pregnancy.

The big central controversy with thyroid disesae at the present time is whether or not to screen all women who are trying to conceive or newly pregnant. We clearly know that overt over- and underactive thyroid disease is bad. We don’t have solid evidence that subclinical disease poses the same risk, or that treating women with subclinical disease improves these possible risks. There are two main professional societies that regularly review available medical evidence and make recommendations on practice guidelines for physicians. The American College of OBGYN currently does not recommend universal screening, on the basis that there is insufficient data to suggest that treating subclinical hypothyroidism improves obstetric outcomes. The Endocrine Society tends to lean more towards liberal screening, however they also do not recommend universal screening. They instead recommend screening any women with the following characteristics:

1. Infertility.
2. History of miscarriage or preterm delivery.
3. History of any thyroid dysfunction, or a family history of thyroid dysfunction
4. Presence of a goiter (enlarged thyroid).
5. Known thyroid antibodies.
6. Symptoms suggestive of disease as outlined above.
7. Type I diabetes.
8. Presence of other autoimmune diseases.
9. Prior head or neck radiation.

Most of the patients we see are infertility and recurrent pregnancy loss patients. In our professional opinion, due to the fact that treatment for thyroid disease (especially hypothyroidism) is generally well tolerated and has few risks, we feel that the benefits of treatment outweight the risks of treatment, and therefore screen most of our patients trying to conceive with a TSH level.

Meet Shan

This is Shan Wilkinson, the embryologist at Tennessee Reproductive Medicine. I was picking on Dr. Murray the other day about how long it has been since his last blog post. He assured me he has done research about his next topic, but he’s still trying to wrap it all up in a nice little blog-package. He then suggested I write my own post to which I laughed, but then I thought I might have a few things to say.

While trying to figure out how to format what I wanted to say, I thought about the weekly Monday Morning Quarterback article by Sports Illustrated writer Peter King. I am a football fan, especially the NFL and specifically the New Orleans Saints (you might remember, they won the Super Bowl) and I like the way King finishes his article with his “Ten Things I Think I Think” section. So, here we go:

Ten Things I Think I Think

1. I think handling 10,000+ cow embryos prepared me for culturing human embryos. It allowed me to learn quickly and to evaluate morphology to help choose the best embryo(s) for transfer.

2. I think handling 10,000+ cow embryos did not prepare me for the emotional investment of “human IVF”. While I’ve been blessed to work in labs with above average pregnancy rates and while I celebrate each positive pregnancy, I think the negatives are difficult to overcome – you should see all my gray hairs! On my way to work one day I heard a verse on our local Christian radio station (J103) that sums up what we do. It is Romans 12:15 “Rejoice with those who rejoice; mourn with those who mourn.” There are many tears shed here for our patients, some of joy and some of sorrow.

3. I think I work for really good doctors. They are both smart and compassionate and hold each other to the highest standards. Our patients have different reasons for choosing the doctor they want to see (male/female, etc.) and some just want the first available appointment, but I believe all patients are in the hands of personable physicians with high morals.

4. I think it’s very difficult for me to make the leap from the ball of 8 to 150 cells in the dish to the baby that a patient brings in to visit after delivery. And if the embryo had been frozen it’s even harder for me to wrap my head around. I am blessed to do what I love to do in a place where I am appreciated. I hope to do it for a long time and I hope I will always make the right decisions to improve the laboratory to help our patients achieve their goals and realize their dreams.

5. I think TRM is a great place to work. I’ve worked in both small and large clinics before and morale can be a problem in any size practice. We have a great group of employees who honestly care for one another without any gossip or jealousy. As all of our job duties become more involved and our work schedules grow, we have to look to each other for support and encouragement.

a. Our office manager works many hours to ensure things are running smoothly and always is available to employees.

b. Our nurses see our patients more than they see their families and they always have a kind word and are ready to explain what this shot is for or what those initials mean. We use a LOT of initials around here!

c. Our front desk/billing ladies are some of the best at what they do. They give patients a face behind the voice on their initial visit and their behind the scenes work helps the office run more efficiently.

d. Our surgery scheduler is brave! After working for many years with the “elder” Dr. Murray, she now works a couple of days with his son, our Dr. Ringland Murray and his partner Dr. Jessica Scotchie. And despite the fact she spends most of her time talking to insurance companies (I think most people would rather have a root canal), she’s always smiling.

6. I think most people I meet have never heard of an embryologist. When asked what I do I say I’m an embryologist. When they say “A what?!” or ask what that is I explain that I put eggs and sperm together in a dish and grow embryos which the doctors transfer and which hopefully become babies. Most people are fascinated and some think it’s a little weird, but almost everyone knows someone who has needed help getting pregnant.

7. I think I cannot tell the difference between X and Y sperm. While I have been accused of choosing more Y sperm than X, there are no differences at the morphological level. If I could select X or Y sperm, we’d probably have a lot more patients and I’d probably make a lot more money.

8. I think almost every male partner is nervous and/or embarrassed by what they are asked to do. It’s normal to be nervous, especially when Dr. Murray is the only other male in our office, but it really is commonplace to us. Humor helps.

9. I think infertility sucks. I have friends and family members who have been affected by infertility and it is heart wrenching. And while some of them can get pregnant with the help of IVF (60 to 70% of women less than 35), it’s a fact that not everyone will get pregnant, including my friends and family members.

10. I think these are my non-embryology thoughts of the blog:

a. My husband is a saint for following me around the country for the last 15 years. I hope the next 15 years (and the 15 after that) we stay a little more rooted.

b. I love living in Chattanooga. We were walking downtown the other day after enjoying some popcorn and ice cream at a Lookouts game and I just really had a sense of feeling at home.

c. I could eat ice cream every day if I had less willpower and more money. I crave ice cream at least once a day.

d. I love my church. In a city with so many transplants, it’s nice to establish a church home where there are people you can count on to do life with you. www.christwaychurch.org

e. I’m so glad Chattanooga finally got a Red Robin! We used to go to one after our trips to Hershey Park when we lived in Pennsylvania.

f. Coffeenerdness: I don’t drink coffee. Although the Mocha Frappe’ at McDonald’s is really good, I don’t think it really counts as coffee more like dessert. I do, however, love a good hot chocolate. If I’m at home I’ll heat up milk on the stove and add either Christopher Elbow’s Cocoa Noir (www.elbowchocolates.com) or Valor Chocolate a la taza. If I’m at work, I make due to with hot water, Swiss Miss Dark Chocolate Sensation, and a couple of squares of Dove Dark chocolate melted in the cup.

g. I’m from Slidell, Louisiana, and yes, my parents’ house did flood during Hurricane Katrina. I know a lot of people are tired of hearing about the storm and now that the 5 year anniversary is approaching they’re going to hear more about it. However, if you or anyone you know was affected by it, you know that time along the Gulf Coast has been divided between before Katrina and after Katrina.

h. I spend a lot of time searching for the perfect dark chocolate truffle. One of my favorites is the Velvet Sin from Chocolate Fetish in Asheville, NC. Well, now Chattanooga is home to a very good chocolatier named Wendy Buckner, owner of The Hot Chocolatier. Her Oatmeal Stout truffle (made with Oatmeal Stout from the Terminal in downtown Chattanooga) rivals the Velvet Sin. She is awesome, her shop is great, and wait until you see her chocolate sculptures! www.thehotchocolatier.com