Antenatal/postnatal medication for women with thyroid or diabetic conditions
Pregnancy and the thyroid
Pregnancy effectively serves as a stress test for your thyroid as it needs to produce 50% more thyroxine to maintain adequate thyroid levels both for the foetus and for the mother.
Healthy thyroids can accommodate these increased demands but 6 out of every 1000 pregnant women will develop hyperthyroidism (normally Graves’ disease) and 2 in every 1,000 will develop hypothyroidism (normally Hashimoto’s Disease). I talk about this in more detail in this blog post
Pregnancy and diabetes
It is a similar scenario with pregnancy and diabetes. Your pancreas will need to triple its output to compensate for the hugely elevated levels of hormones being produced by the placenta. Most women’s bodies will naturally accommodate this but some will develop gestational diabetes – which I discuss here
So pregnancy will cause some women to begin medication to bring balance and some will require increased medication for those with pre-existing conditions. But what happens post-delivery?
Women previously on Levothyroxine will have required a 25% to 50% increase in dosage from early pregnancy in order to remain euthyroid (this is the term for having a normally functioning thyroid). This dosage will have been increased in line with regular monitoring throughout.
Hypothyroid women are usually reviewed 6 weeks after labour by means of a TSH test and most women return to their pre pregnancy dosage.
Don't worry, your baby will have been given a heel prick test shortly after birth and this will have indicated if the baby was hypothyroid.
It's safe to breastfeed while you're on Levothyroxine as thyroid hormones pass into breast milk in levels that are too small to affect the baby. It’s important to continue taking your medication in order for your body to have the ability to produce sufficient breast milk
An anti-thyroid medication which blocks the production of thyroid hormones is usually given in the first trimester. As these drugs can cross the placenta the increased dosage is as low as possible and the medication may be switched from Carbimazole (SMZ) to Propylthiouracil (PTU) for those three months.
The risk of relapse in terms of Graves’ disease is high for about a year after labour so you should arrange for your blood to be tested at three months and at intervals thereafter.
If you are on low levels of antithyroid drugs it is safe to breastfeed. However, you might like to consider taking your antithyroid drugs in smaller doses two or three times a day after you have breastfed the baby.
- Postpartum thyroiditis
Some women are at risk of postpartum thyroiditis. This is those with
- Type 1 diabetes
- Another autoimmune condition
- High anti TPO antibodies in early pregnancy or post labour
- A history of thyroid problems connected with this or a previous pregnancy
If this is the case you should make an appointment with your GP to be tested. You will be prescribed medication if there is a problem. Most women recover from this within 6-12 months but some do go on to develop permanent thyroid problems
4. Type 1 diabetes
Most women using pump therapy can continue to use this through delivery but they may additionally need an IV insulin/dextrose drip either during labour or immediately after delivery your when insulin levels will drop significantly.
After this you are likely to go back to your normal levels of medication. However, this is not the case if you are breastfeeding.
This is because breast milk contains lactose which means your blood sugar level drops every time you feed, so you may need about 25% less insulin during this time. Since you are also more vulnerable to a hypo whilst breastfeeding it is good to keep a snack within easy reach.
5. Type 2 diabetes
If you are taking metformin it is safe to do so whilst breastfeeding.
This normally resolves post-delivery but your glucose levels will be measured before you leave the hospital and again at 6-13 weeks after the birth.
However, data suggests that 66% of women with gestational diabetes will go on to develop type 2 diabetes within 15 years. Unfortunately this risk increases for older women and for Asian women.
I hope you have found this helpful.
Although every effort is made to ensure that all health advice on this website is accurate and up to date it is for information purposes and should not replace a visit to your doctor or health care professional.
As the advice is general in nature rather than specific to individuals Dr Vanderpump cannot accept any liability for actions arising from its use nor can he be held responsible for the content of any pages referenced by an external link