What you need to know about your thyroid in pregnancy
Issues with your thyroid are common in the baby-making years. In Australia about 2-3% of pregnant women are hypo or hyperthyroid. Then there is post-partum thyroditis.
Post-partum thyroiditis is something that happens to 1 in 20 women after their baby is born.
This needs careful assessment because the signs and symptoms can be dismissed as just part of having a newborn or it can look like postnatal depression.
In this podcast we talk about:
What the thyroid gland does in our body
What is hypo and hyperthyroidism
What are the special plans you have to make pre-pregnancy
What changes during your pregnancy if you have problems with your thyroid
What medication you can take during your pregnancy
What is post-partum thyroiditis
Photo by @sisterscout_
Brigid: [00:00:36] Well, welcome everyone to episode 36.
Dr Pat: [00:00:39] Welcome everybody.
Brigid: [00:00:40] Yes. We are going to talk about thyroid disease in pregnancy. This is another listener request. We love our listener requests.
Dr Pat: [00:00:46] It makes it easy. That's why we get to talk about things that are of interest to people who are listening. And of course, some of it is really core stuff like thyroid. Common!
Brigid: [00:00:57] Common. It is common. Isn't it? So how we get to know what you want to hear is that people send us DMs in our Instagram. So, if you're not already our friend on Instagram, stop everything right now.
Get on Instagram, follow us at, @grow_my_baby and come and join us and send us a DM. We love hearing them all even. Pat dare I say sometimes the bad. I know we got a one star review. Yes we did. And it's on our iTunes and her tagline or his tagline is “not an online commenter” one star.
Brigid: [00:01:39] “You lost me at the claim that women need red meat during pregnancy”
Dr Pat: [00:01:43] Yes. We discussed this
Brigid: [00:01:45] “This is patently untrue plant based diets are very safe and in most circumstances, a lot healthier than non plant based”
Dr Pat: [00:01:51Uh, yeah. Yeah. Okay. That reminds me of that hotel review. We saw we were in Sydney once and we were checking out this hotel where we were staying and someone gave it a one star review. Yeah, because they'd got the bill wrong.
Brigid: [00:02:06] Right.
Dr Pat: [00:02:07] And do you remember this? And they said, um, this was on TripAdvisor and the hotel was given the opportunity to respond. Yeah. And the guy from the hotel said, “I'm interested in your five star system. You seem to have allocated four stars for bill accuracy in one star for everything else”.
So maybe this is that, four stars for iron advice and one star for the entire rest of the podcast
Brigid: [00:02:36] We can't even think about when that was. When, when would we have even said that?
Dr Pat: [00:02:39] You need iron? Yes. When you're pregnant and there are different ways to get it. Most people in our community eat some red meat and that's a very bioavailable way to get it.
Your gut gets iron very efficiently from red meat. Iron supplementation is very important. I believe for people who don't eat any or much red meat. And if you eat no red meat at all, and you're not on an iron supplement, then getting the iron that you need for pregnancy is going to be very difficult, the commentor might be correct that it’s possible.
Brigid: [00:03:15] She might be a very motivated vegetarian.
Dr Pat: [00:03:18] Yeah. So that person may be correct. That it's possible. I would very much take issue with the idea that it's safer. I would say that's not true that I don't, I don't think it matters where you get your iron from. So from plant sources, it's a big stretch to say it's safer.
Brigid: [00:03:37] I think she might be sort of referring to the fact that we all eat perhaps too much red meat.
Dr Pat: [00:03:42] Well, that's a different question about the safety of that over our whole lifetime, but in pregnancy, there's nothing wrong with getting your iron that way. So safer? I don't think so but possible, yes. But I think if you're going to try and do it, you're going to need expert advice from a dietician comfortable working in the pregnancy space.
Brigid: [00:04:02] Absolutely. And I think that's what we discussed after we saw our one star and cried a little bit and then, um, came back to it. And then actually it's true. We know some vegetarians that are very motivated and have a very good balanced diet but just like a lot of people that are meat eaters there are people that are bad meat eaters aren’t there?
Dr Pat: [00:04:25] And vegetarians who
Brigid: [00:04:26] survive on Mac and cheese
Dr Pat: [00:04:28] who get by when they're not pregnant, but are in potential trouble when they are pregnant. Yeah. You've got all that extra iron need.
Brigid: [00:04:36] Yep. And so what that meant for us is that we will do a podcast on iron.
Yup. Um, and we'll do it from Pat's medical point of view, but we'll also bring in a dietician.
Dr Pat: [00:04:46] I think that'd be perfect. Yep. And the take home message would be that if you're going to try it without red meat and without iron supplementation, then you're going to need to learn a lot about how to get iron from plant sources.
Brigid: [00:04:59] Yeah. It goes for every diet. Actually we've got a dietician in the grow my baby program, Melanie McGrice. And during those interviews that you do with her Pat, you say that actually everybody could see a dietician. Yeah. Yeah. And it's so easy to do that because you can do it via zoom or Skype or whatever.
Even a half hour online consultation I think is probably well worth it.
Dr Pat: [00:05:22] I reckon dietitians. I mean, I'm sure there's some extra value in seeing them face to face, but it's probably one of the allied health options for people that really quite suits the online environment. Yeah. A lot of it's going to be telling that person what you eat and they can talk to you about the value of this and that and making plans and food diaries and so forth.
And I can't, I can't see why that wouldn't work quite nice.
Brigid: [00:05:46] Yep. Excellent. Alright. Well, and thank you ‘Notanonlinecommenter’ for making us, you know, evaluate and clarify excellent. All right. So we are going to talk about thyroid disease in pregnancy, and you talked just briefly then about how common it is Pat, but how often do you see it?
Dr Pat: [00:06:05] Yeah, so again, a bit more than I thought. So two to 3% of women who are pregnant in Australia are either hyper or hypo thyroid.
Brigid: [00:06:15] What does that actually mean? Like if we go back to basics again, it's a bit like our, um, last week's podcast, can we talk about what is hyper or hypo thyroidism
Dr Pat: [00:06:25] okay, well, let's go right back to basics of thyroid.
The thyroid gland is located in our neck and it's a really important gland that makes thyroid hormone and thyroid hormone works in our body to control lots of critical parts of our metabolism. From heart rate to digestion, to reproduction and disorders of the thyroid gland are reasonably common and they sometimes run in families and they're reasonably common in the pregnancy age group.
Brigid: [00:06:55] And what would make me think that I'm either hypo or hyperthyroid?
Dr Pat: [00:06:59] Well, sometimes we just check in people who have illnesses that are known to be part of thyroid metabolism. So for example, I would always check the thyroid in someone who presents, where their periods have disappeared. Oh, right. Cause that can be a symptom of hypothyroidism. So we would check that.
Brigid: [00:07:17] Hypo did you say?
Dr Pat: [00:07:18] Yeah, you could have someone who had a complex infertility problem and would definitely have thyroid function tested as part of that. And then sometimes people have overt symptoms. So hypothyroidism is it not enough thyroid hormone, tends to cause things to generally slow down.
Um, so people would present with tiredness and lethargy among other symptoms and hyperthyroidism is too much thyroid hormone, the easy way to think about it that is the things that too fast. So they might present with tremor, a high heart rate.
Brigid: [00:07:49] Yep. Um, and if somebody is looking at sort of like I do, when I go to the GP and get a blood test and you look out at the sheet afterwards and there's lots of acronyms and you think, I don't know what that is. Is that TSH?
Dr Pat: [00:08:00] So TSH is a bit different. That's thyroid stimulating hormone. That's the hormone that comes out of your brain to tell your thyroid to make thyroid hormone. And TSH is actually quite a nice way of measuring thyroid function. Because rather than measuring the output of the thyroid hormone itself, you can just measure the TSH, which is easy to do.
And if it's telling the brain to make the right amount, then the thyroid hormone is probably making the right amount. Yeah. The negative feedback loop if the thyroid is going too hard. it'll drop the TSH and the brain will say ease up on the thyroid hormone.
Brigid: [00:08:37] Yeah. Right. And so when you have a blood test, what else are they checking for?
Dr Pat: [00:08:41] Well, we commonly check just TSH as a screening test. If that's normal things normal and getting into more detail in someone who's got an actual thyroid problem, then we check for the types of thyroid hormone. There's one called T3 and one called T4. In pregnancy T four is most important. It crosses the placenta into the baby, and then the baby will metabolize that into T3, which then the baby will use to make sure it's most importantly, that the brain is forming properly and that the baby's reaching full potential for neurological development, intellectual potential
Brigid: [00:09:16] Wow. So what can a woman do? Like, you know, I'm sure that is everybody got a good level of thyroid, that is not in the two to 3%, but are there sometimes, you're just dipping below the cut off level.
Dr Pat: [00:09:30] It only has to be normal. It's not one of those things that more is better, but there's a bit of question about whether we should universally screen for this and we don't.
Brigid: [00:09:39] So it's not in the first lot of blood tests?
Dr Pat: [00:09:40] A lot of the time it's there anyway, and that's just some diligent GPs are testing for it anyway, put a TSH level in that first blood with the rubella and the haemoglobin and the HIV and hepatitis test and so forth. But it's not officially on that list. There is however, a checklist of people who might be at higher risk of thyroid disease.
And that includes things on it like whether you've got a family history. Being over 30
Brigid: Like a lot of people are!
Dr Pat: and having other auto immune diseases in your body. Oh, if you've also got eczema another condition where the immune system is prone to attack your own tissue. So a lot of people will pass that checklist and have a TSH tested at the start of pregnancy.
Brigid: [00:10:29] Yeah. That just reminds me to remind people that if you're listening to this and your just pregnant, we do have our checklist that you can download off our website. So head over to that and click on the, ‘just pregnant’. And so that you can print that out and you can see what you will discuss and what tests that you might have at your first visit with your GP,
Dr Pat: [00:10:52] which is good to be prepared for.
Brigid: [00:10:54] So you don't forget to ask for things. Would you suggest that women ask their GP to test for T S H?
Dr Pat: [00:11:01] Well, I think they should go through the checklist and go into that first visit with the local doc with a good picture in their mind of their health today. If there are any issues that's the chance to bring them to the GP’s attention so that you can come into the early part of that pregnancy with any preexisting medical conditions optimally managed.
Brigid: [00:11:22] Yep. And what's the iodine got to do with it.
Dr Pat: [00:11:24] Your thyroid gland needs iodine to work properly to make thyroid hormone. And when you're pregnant, the gland needs to make more thyroid hormone, which it can do if there's enough iodine.
So a person without a thyroid problem won't need supplementation of thyroid hormone, but they will need some extra iodine and the gland will then go ahead and make it. And there's iodine supplementation in some of our foods, they have added some iodine into bread and other commonly eaten things. And if you get that bit of extra iodine from those sources or from a pregnancy multivitamin, then a normal thyroid gland will have no trouble upping the output of thyroid hormone by about 50% to take care of the needs in pregnancy.
When you're pregnant, the kidneys are working harder and it wees out a bit of the iodine and your plasma volume increases. So you've actually, you've got more blood when you're pregnant. It's got to go down through that big tummy and through the placenta. And so the thyroid hormone is over a greater distribution within your body.
So you need more to keep the concentration the same.
Brigid: [00:12:29] Yeah. And so women should, well we're hoping that most people by then are on a multi, so their iodine would be covered by that, but also you can concentrate on things that have got high iodine in it.
Dr Pat: [00:12:39] Sure. So there's some seaweed. Yeah, sure. Yeah. So some people would be keen enough to follow that.
And other people say, I'll just take the pregnancy multivitamin and then yeah.
Brigid: [00:12:48] Yeah, we put dulse flakes in, well, you don't know that, but I sneak that into all our stews. That's good. Good for iodine.
Dr Pat: [00:12:55] I don't even know what that is.
Brigid: [00:12:57] Good. All right. So once you've had your first test, but during the pregnancy, do you get it tested for your thyroid function?
Dr Pat: [00:13:04]
We'll know if it's normal at the start it's normal. It's normally fine unless you develop symptoms, I guess, but no, if you've got a problem, then it needs quite a bit of testing at that point. If someone's got known hypothyroidism or known hyperthyroidism then again, that's one of those important things that I ideally we would have addressed before you're pregnant.
So sometimes that's possible sometimes that's not, but let's say the pregnancy isn't a big surprise and it was a planned pregnancy. Then the ideal thing for that woman to do is to go along to her GP to talk about that beforehand. And if the GP is all over thyroid, they'll be able to make a plan that's appropriate leading up to the pregnancy. If thyroid is not really their thing, they might involve an endocrinologist at that point. Maybe you've already gotten endocrinologist specialists, gland specialist, looking over their problem, and a plan would be made so that the woman was on suitable medication up to the time of pregnancy.
And then if it's managed, well, things would go quite smoothly.
Do you think it's worthwhile sort of talking more in depth about hypo thyroidism as opposed to hyperthyroidism?
Dr Pat: [00:15:24] Definitely, hypothyroidism that's when you've got not enough thyroid hormone. So, you know, I imagine that maybe that's someone who in the past has presented with tiredness and lethargy and been found to be hypothyroid.
Now that woman would have been treated with a drug called thyroxine, which is synthetic thyroid hormone. And it tends to work extremely well and people will develop long term stable levels.
Brigid: [00:15:47] And can you take thyroxine in pregnancy?
Dr Pat: [00:15:49] Yeah, but the exception to the long term stable dosing is pregnancy. So it can be quite difficult as well, more complex to get the dosing.
Right. So for example, a woman who's pregnant might have a thyroid function test every month at the start. And at least once per trimester, to make sure that we're replacing the right amount and that, that right amount has factored in the increase for pregnancy
Brigid: [00:16:13] Can pregnancy cause you to be hypothyroid?
Dr Pat: [00:16:15] Yeah. So you can, you can develop it when you're pregnant. Absolutely.
Brigid: [00:16:18] So that's hard. Isn't it? We just put up a post a little while ago where we had someone that was just exhausted and it was ‘just frigging tired’. Like, you know, You so tired in that first trimester, how can someone tell that it's because of the pregnancy or because of something like hypothyroidism?
Dr Pat: [00:16:35] So that's, um, a challenge, um, tiredness, as we covered in our podcast on early pregnancy symptoms is practically universal. And I start thinking of other diagnoses, if it's way more severe than normal or way more protracted than normal.
Brigid: [00:16:50] Yeah. Yeah. So way more severe that person can't get out of bed or
Dr Pat: [00:16:53] Yes if you're tired at nine weeks, but you're better by 12.
Yes. That's normal. If the problem persists, then sure. We start checking some other things and thyroid , it's pretty easy to check. Yup. And so in hypothyroidism, the dosage of thyroxine needs to be watched more closely in pregnancy factor in the higher needs, but tends to go very well.
Hyperthyroidism can be more complicated.
That's the person with too much thyroid hormone. And that's because a woman with hyperthyroidism may be on some drugs to control that that may well be quite relevant. Yeah. There's a drug called carbimazole which is in common use for hyperthyroidism, but it's not the ideal drug for pregnancy can be associated with a rare complication called aplasia cutis. This is where the baby's missing some skin on the top of their head. There are better drugs for pregnancy. So we might change that woman over from that drug to another one for the duration of the pregnancy, and then go back afterwards. And then some women with hyperthyroidism have had that condition treated surgically
Brigid: [00:18:00] they've had their thyroid removed?
Dr Pat: [00:18:02] Yes a thyroidectomy.
And therefore there'll be naturally hypothyroid because the glands being removed. So they're going to have the hypo thyroid picture in pregnancy. Yeah. And similarly to similarly someone who's, might've had their thyroid treated with radioactive iodine. So that's another treatment
Brigid: [00:18:19] for hyperthyroidism.
Dr Pat: [00:18:20] yeah. Yeah. So what's been done in the past for that person it's highly relevant to their subsequent pregnancy needs. And remember these sort of thyroid conditions are common in young women. So it's commonly something that affects all. It’s not just an old person's thing. It's something that comes up for people who haven't had their babies yet.
Brigid: [00:18:39] And actually we didn't cover it, but you know, even getting pregnant, is there a problem with women who have got a thyroid problem and getting pregnant in the first place?
Dr Pat: [00:18:46] Yeah. I guess the person who's got the known thyroid problem is the one you're least worried about
Brigid: [00:18:51] yeah. Yes. Because you know how to manage that and treat it and
Dr Pat: [00:18:53] okay.
Properly managed. Exactly. So disturbances of thyroid function, hyper or hypo can cause problems with ovulation. And it's definitely something we check. If we think that the woman's underlying fertility issue is one of not making an egg at all, or at least every month. Yeah. And so that person will be managing that it will be on top of the issue.
We'll have normalized the thyroid if we can. And we'll be okay. Making sure that she's ovulating. So she gets pregnant. Promptly. Yeah. It's the undiagnosed person, I guess, that we're more concerned about. And that's why testing thyroid is part of an infertility workup.
Brigid: [00:19:28] All right. So the person's gone through a pregnancy and a labor and you've got a little baby, which is all very exciting.
One of the reasons why we want to do this topic is because somebody asked us about postpartum thyroiditis have I said that, right?
Dr Pat: [00:19:40] Yeah. Postpartum. Thyroiditis. Yeah. Yeah.
Brigid: [00:19:43] Just had to practice it.
Dr Pat: [00:19:45] That's what you don't want. So that's a post pregnancy phenomenon where the thyroid gland, you know, plays up after pregnancy.
And that's actually pretty common about one in 20 women.
Brigid: [00:19:57] What that already had a thyroid problem?
Dr Pat: [00:19:59] No flat out one in 20, and that's where a lot of thyroid disease comes from it. Someones been totally normal. Hasn't had thyroid problems in pregnancy, but gets postpartum thyroiditis. And it's just where the gland becomes really inflamed.
And sometimes that's symptomatic the woman can actually feel it. Sometimes it's not.
Brigid: [00:20:16] So tell me if they can feel it. Where are you feeling that
Dr Pat: [00:20:19] it's in the neck,
Brigid: [00:20:20] where though just underneath your Jawbone
Dr Pat: [00:20:23] is sort of the trachea and it might actually swell up, but sometimes it doesn't put the diagnosis is there none the less.
And it's got a bit of a mixed picture. Sometimes when it swells up, it will go hypo. Yeah. And sometimes it will go hyper and sometimes it will go a phase of hyper followed by a prolonged phase of hypo. Yeah. Wow. And
Brigid: [00:20:46] because your hormones are just been kind of free fall after you have a baby. Well, it's over simplistic, isn't it?
Dr Pat: [00:20:51] Perhaps oversimplifying it a little bit, but you know, it is what it is.
It's a risk and it's something we need to be closely looking out for. And not confusing, for example, with postnatal depression.
Brigid: [00:21:01] Yeah. Because like, if you're lethargic, you can't get out of bed.
Dr Pat: [00:21:05] Yeah. Yep. So we have to have what they call a low index of suspicion. We've got a be, or is it high index of suspicion?
We've got to be on the look suspicious and on the lookout. Yeah. For, uh, for thyroid diseases in the first few months after a baby. And typically, you know, I would use the help of a clever endocrinologist to help me manage that. Yeah, mostly the one that's got two phases, cause there's going to be high, too high for a while and then too low.
And occasionally that too low bit will be permanent.
Brigid: [00:21:30] Wow. God. And I wonder how many women know that, say that have dealt with hypothyroidism and they're 10 years on from having their baby.
Dr Pat: [00:21:38] They've still got it 10 years on? Yeah. That it might've started way back then.
Brigid: [00:21:43] Got somebody in mind for that. I've just learnt so much in this podcast.
Um, one, I didn't know about the one in 20. Postpartum thyroiditis. That to me is kind of shocking.
Dr Pat: [00:21:52] It's a big figure, isn't it? Yeah. But again, typically, um, you know, capably managed and just need to be aware of it.
Brigid: [00:21:59] Yeah. Because again, you know, for a lot of women you're sleep deprived. Yes. You're exhausted.
I think I recall telling you that I felt just like I was weary right down to my very core and that was just. You know, postpartum normalness.
Dr Pat: [00:22:15] Yes, that's right. But I think thyroid,
Brigid: [00:22:18] But I had you to tell me that like, you know, people would be really concerned.
Dr Pat: [00:22:21] I think one of the things that's really done very well in general practice is awareness of thyroid disease and testing that for people in particular,
Brigid: [00:22:29] but a woman's got to want to, and be able to get out up out of bed to get to the doctor in the first place.
Yeah. All right. So if you're experiencing any of those symptoms, that's where your six week postnatal check is super important
Dr Pat: [00:22:42] and beyond
Brigid: [00:22:43] and beyond that's right? Because it's not just that once you have a baby, it's not just the six weeks it's it's forever.
Dr Pat: [00:22:50] There's going to be some potential health issues that date back right to the pregnancy, um, that might need.
Attention for some time.
Brigid: [00:22:56] Yes. Um, I'm what nearly seven years on and still dealing with my hip from, uh, my last pregnancy. It happens. It does happen. All right. Well, everyone, I hope that was really, really informative. We'd love to hear your feedback, jump online and, tell us if you've had any thyroid issues when we post this.
Um, and we'll look forward to
Dr Pat: [00:23:16] chatting to you then. Thanks for listening everybody.