My Personal Experiences / Pregnancy and Parenting

My Third Trimester: Pregnancy with NDT, Hypothyroidism and Hashimoto’s

My Third Trimester: Pregnancy with NDT, Hypothyroidism and Hashimoto's

Read My Second Trimester: Pregnancy with NDT, Hypothyroidism and Hashimoto’s blog here.

Going through a pregnancy with Hashimoto’s and hypothyroidism and being on unconventional medication for this (NDT – Armour) definitely presented some extra questions and challenges.

I was very anxious about the prospect of a pregnancy with my thyroid conditions, and in particular, in regards to whether me not being on Levothyroxine (like most people with hypothyroidism) would make it a more stressful experience. I wanted to blog about my experiences of going through pregnancy on Armour NDT, in order to give an insight in to how this medication worked for me during this time, but also as to how medical professionals reacted to it.

I’m in the UK and besides my NDT thyroid medication being prescribed by a private doctor, all other healthcare was on the NHS unless otherwise stated.

The third trimester is commonly said to be anytime from week twenty-eight onwards.


Pregnant With Hypothyroidism and Hashimoto's

Third Trimester Appointments

A routine midwife appointment at twenty-eight weeks went well. Baby was measuring perfectly and being very active. We also heard his heartbeat again.

At twenty-nine weeks, I had another thyroid blood test (they were being done every 4-6 weeks throughout pregnancy). The results showed that my Free T4 was only just within range and my Free T3 had dropped too. Being on NDT medication, my TSH was suppressed, as expected. Both the NHS GP and private GP agreed that an increase in my medication was finally needed, so we raised the dosage and then retested in another 4 weeks’ time. Before now, I hadn’t needed any dosage increase at all. (Read about this in my first trimester blog here and second trimester blog here.)

The results that came back after the increase 4 weeks later showed that my levels were now optimal again, however, I did have to remind the NHS GP to use the pregnancy thyroid test ranges as opposed to the regular ones (which are different). On the regular ranges, my levels were considered low in range still, but using the pregnancy ranges, they were indeed optimal.

The ranges used on my thyroid tests whilst pregnant were the following:

(Non-pregnancy range for TSH is usually around 0.5 – 4.4 mu/L)

  • 1st Trimester: 0.09 – 2.83 mu/L
  • 2nd Trimester: 0.2 – 2.8 mu/L
  • 3rd Trimester: 0.31 – 2.9 mu/L

Free T4:
(Non-pregnancy range for Free T4 is usually around 10 -20 pmol/L)

  • 1st Trimester: 10.5 – 18.3 pmol/L
  • 2nd Trimester: 9.5 – 15. 7 pmol/L
  • 3rd Trimester: 8.6 – 13.6 pmol/L

Free T3:
(Non-pregnancy range for Free T3 is usually around 3.5 -6.5 pmol/L)

  • 1st Trimester: 3.5 – 6.2 pmol/L
  • 2nd Trimester: 3.4 – 5.8 pmol/L
  • 3rd Trimester: 3.3 – 5.6 pmol/L

Something worth keeping in mind is that HCG, the pregnancy hormone, stimulates the thyroid, often leading to a lower TSH compared to before pregnancy. This is why test ranges change for pregnant women.

My iron levels also came back a bit low, so I was started on an iron supplement. I took Bisglycinate as it’s easy on the stomach.

At thirty weeks, I was booked in for an extra scan because I had a day of reduced movements from baby, so they checked him over and thankfully everything was still going well. He just seemed to be having a quieter day. He was actually measuring slightly ahead still.

I had another midwife check up at thirty-one weeks, which showed that my liver test results were still coming back normal. At thirty-four weeks, we had another completely normal and positive check up appointment, with baby measuring two weeks ahead still.

At thirty-five weeks, I ended up having another extra ultrasound scan after having a bad fall at home. Besides my bruised knees and sciatica, I was OK and baby was too. The scan confirmed he was measuring two weeks ahead still and was a very healthy weight. This was reassuring as a thyroid patient.

At thirty-five weeks I had another iron and liver test which came back good. My third trimester was progressing very smoothly, with no concerns from anyone.

I had another routine midwife appointment at thirty-six (almost thirty-seven) weeks. Baby was measuring on-time and everything was looking good. I had opted for a birth at a midwife-led unit from the beginning and was on track to have this. The midwife gave me some essential oils to use now and during birth (for massage and burning).

Another routine midwife appointment at 38 weeks and 6 days was also all positive. Baby was still head down and engaged. Ready to go.

Third Trimester Pregnancy with Thyroid Condition

How My Health Was in The Third Trimester

Week 28

I didn’t have much of an appetite at all, as I felt very full all the time. I was experiencing a lot of indigestion and heartburn. I also noticed that I was getting tired quicker when walking, but I enjoyed a lot of soaks in the bathtub to ease my achey legs and feet (Epsom salts were helpful).

I managed to avoid catching any illnesses up until this week, when I unfortunately caught a nasty cold which really wiped me out. Stretch marks also appeared this week (see below Instagram post) and my skin was super clear of acne for the rest of pregnancy from here on out.

Week 29

I experienced some rib pain (front and back) and leg cramps. The weight of how heavy the baby was to carry around suddenly hit me, along with more indigestion and period-like cramps.

Week 30

Increasing my magnesium supplement amount stopped the leg cramps and also slight constipation I was experiencing. Still feeling full all the time and quite bloated, I also noticed my first bit of milk production on my pyjama top!

Week 32

Braxton hicks started, which I noticed were a lot more frequent when walking or active. They weren’t painful but quite unusual in feeling!

Week 33

The sciatic pain from quite a while ago reappeared again and I felt a lot of pressure low down. Mood swings made me feel quite grumpy and emotional at times and I was finding work increasingly more uncomfortable. Walking was triggering a lot of round ligament pain, but yoga and swimming were good.

I saved up for a spa day and took this at 33 weeks as well, which definitely helped ease a lot of those symptoms.

Week 34

Lots of reflux and feeling uncomfortable when sitting meant that I eventually caved and invested in a pregnancy/fitness ball. It helped a lot with the reflux, back ache and sciatica.

I started napping quite a bit during the day and had visible bags under my eyes. Hot flushes at night reappeared and I experienced a few thyroid flare ups due to overcommitting myself and agreeing to too many social events. Adam and I made the decision to prioritise being at home and resting whenever possible from now on.

I also started hypnobirthing this week.

Third Trimester Pregnancy with Thyroid Condition

Week 35

I felt uncomfortable in one way or another pretty much all the time now. The sciatica was occurring more regularly, as well as thyroid flare ups, and baby was keeping me awake at night with his ‘partying’, which didn’t help! I felt tired and achey pretty much all the time, but it was different to ‘thyroid tired’. It was definitely due to pregnancy as I just felt the weight of the bump drain me much quicker than usual. He was feeling so heavy to carry around and I was very aware of his size, as I kept knocking in to things with my belly!

My feet started to swell a little, and my fingers were still a little swollen (which started towards the end of the first trimester). I was waking up with cramps in my hands which the midwife explained is due to reduced circulation and extremely common late in pregnancy.

Week 36

Back ache and period-like cramps would come and go during the day. I was still having days where all I could do was rest and if I didn’t, the sciatica became excruciating. Diarrhoea was back unfortunately. Baby dropped this week.

Week 37

Officially classed as ‘full term’, I felt much like the week before. Back ache, light stomach cramps and overall quite tired.

Week 38 

Stomach cramps and back ache continued, with more braxton hicks, too. Baby dropped further, which made swimming much easier than walking! Diarrhoea was daily (pleasant – not!), with lots of signs that labour wasn’t too far away. I couldn’t walk for longer than 20 minutes or so before feeling quite tired and my stomach cramping quite a bit.

Week 39

Diarrhoea, tiredness, achey feet and lower back pain, some pelvic pain and mood swings made this week fun!


You can click on the hyperlinks in the above post to learn more and see references to information given.

Read other articles and blogs in my ‘pregnancy’ category here.

 Related Articles:

Were My Thyroid Pregnancies What I Expected?

9 Ways I Supported My Thyroid Health Postpartum

New Baby and Hashimoto's

Books I found useful in my pregnancy:

A Book for Our Children:

Thyroid Superhero: A Kid’s Guide To Understanding Their Grown-up’s Hypothyroidism, which helps children to understand their caregiver’s thyroid medication, flare days, symptoms and much more.

About Author

Rachel Hill is the highly ranked and multi-award winning thyroid patient advocate, writer, speaker and author behind The Invisible Hypothyroidism. Her thyroid advocacy work includes writing articles, authoring books, producing her Thyroid Family email newsletters and speaking on podcasts and at events about the many aspects thyroid disease affects and how to overcome these. She is well-recognised as a crucial and influential contributor to the thyroid community and has a large social media presence. Her bestselling books include "Be Your Own Thyroid Advocate" and "You, Me and Hypothyroidism".

No Comments

    Leave a Reply