Now you’ve had your baby, has your diabetes gone?

Gestational diabetes increases the risk of developing Type 2 diabetes after pregnancy and therefore post-birth diabetes testing is very important.

new mother holding newborn thinking

Statistics from Diabetes UK​1​ and from a meta-analysis of 20 studies published in the Lancet​2​, states that there is a seven-fold increased risk of women with gestational diabetes developing type 2 diabetes in later life. NICE​3​ states that up to 50% of women diagnosed with gestational diabetes develop Type 2 diabetes within 5 years of birth.

A 2002 publication from Diabetes Care​4​ comparing 28 studies found that elevated fasting levels during pregnancy were the most common risk factor associated with future risk of Type 2 diabetes:

Cumulative incidence of type 2 diabetes increased markedly in the first 5 years after delivery and appeared to plateau after 10 years. An elevated fasting glucose level during pregnancy was the risk factor most commonly associated with future risk of type 2 diabetes.

Gestational Diabetes and the Incidence of Type 2 Diabetes: A systematic review
blood glucose monitor showing a high fasting reading

Post-birth diabetes testing

NICE​5​ recommends that those diagnosed with gestational diabetes should have a fasting glucose blood test at 6 weeks post-partum OR an HbA1c blood test after 13 weeks post-partum to check that they do not have diabetes.

Women diagnosed with gestational diabetes are offered a test of their blood glucose to check whether they have persisting hyperglycaemia (high glucose levels) after they have given birth, before they are transferred to community care. If they do, they will receive treatment for this. If they do not, they are offered another test of their blood glucose 6 to 13  weeks after their baby is born to check again whether they have type 1 or type 2 diabetes. If they do not have this test by 13 weeks following their baby’s birth, they are offered testing afterwards. They are also offered referral to the National Diabetes Prevention Programme to help to reduce their risk of developing type 2 diabetes.

NICE, Diabetes in pregnancy, Quality standard [QS109], January 2023
NOTE: some practices may take BOTH an HbA1c and a fasting blood glucose test at the same time

It is no longer recommended that a repeat oral glucose tolerance test [GTT] is performed to check that the diabetes is clear (NICE guidelines Dec 2020). However, it may still be offered in Scotland and Ireland or in NHS Trusts who are not following the NICE recommendations and quality standards.

Many mothers have concerns over taking a fasting blood glucose test whilst breastfeeding or attending blood tests for long periods of time whilst their newborn is still very young.  If you have these concerns then you may want to opt for an HbA1c blood test after 13 weeks post-partum. You do not need to fast and it is one simple blood test that can be taken at any time of day at most local GP surgeries.

High blood sugar levels after giving birth

You should eat a normal diet following the birth of your baby. Some hospitals will advise continuing to test blood sugar levels after giving birth. Be prepared that you may see some high readings if you do this. It can take a while for your hormones to settle, hence the reasoning behind the recommendation of being properly tested for diabetes after at least 6 weeks.

If you feel unwell or experience hypo or hyper-type symptoms then you should test your blood sugar levels and consult a medical professional.

Post-birth test results

normal and diabetic blood glucose levels

The World Health Organization​6​ (WHO) advises that the range of blood glucose indicative of diabetes mellitus is as follows:

  • fasting venous plasma glucose (FPG) ≥7.0 mmol/l; or venous plasma glucose ≥11.1 mmol/l at two hours after a 75 g oral glucose load (oral glucose tolerance test (OGTT)).
  • HbA1c of 48 mmol/mol (6.5%) is recommended as the cut-off point for diagnosing diabetes
WHO [World Health Organization] diabetes diagnostic criteria

National guidelines for post-birth diabetes testing

NICE guidelines for England & Wales

Information and follow-up after birth

Women diagnosed with gestational diabetes

1.6.8 Before women who were diagnosed with gestational diabetes are transferred to community care, test their blood glucose to exclude persisting hyperglycaemia. [2008]

1.6.9 Remind women who were diagnosed with gestational diabetes of the symptoms of hyperglycaemia. [2008]

1.6.10 Explain to women who were diagnosed with gestational diabetes about the risks of recurrence in future pregnancies, and offer them diabetes testing when planning future pregnancies. [2008, amended 2015]

1.6.11 For women who were diagnosed with gestational diabetes and whose blood glucose levels returned to normal after the birth:

  • offer lifestyle advice (including weight control, diet and exercise)
  • offer a fasting plasma glucose test 6 to 13 weeks after the birth to exclude diabetes (for practical reasons this might take place at the 6‑week postnatal check)
  • after 13 weeks offer a fasting plasma glucose test if this has not been done earlier, or an HbA1c test if a fasting plasma glucose test is not possible
  • do not routinely offer a 75-g 2‑hour OGTT
  • offer a referral into the NHS Diabetes Prevention Programme if eligible based on the results of the fasting plasma glucose test or HbA1c test. [2015, amended 2020]

1.6.12 For women having a fasting plasma glucose test as the postnatal test:

  • Advise women with a fasting plasma glucose level below 6.0 mmol/litre that:
    • they have a low probability of having diabetes at the moment
    • they should continue to follow the lifestyle advice (including weight control, diet and exercise) given after the birth
    • they will need an annual test to check that their blood glucose levels are normal
    • they have a moderate risk of developing type 2 diabetes, and offer them advice and guidance in line with the NICE guideline on preventing type 2 diabetes (note that this guideline uses different risk thresholds, because it covers a different population).
  • Advise women with a fasting plasma glucose level between 6.0 mmol/litre and 6.9 mmol/litre that they are at high risk of developing type 2 diabetes, and offer them advice, guidance and interventions in line with the NICE guideline on preventing type 2 diabetes (note that this guideline uses different risk thresholds, because it covers a different population).
  • Advise women with a fasting plasma glucose level of 7.0 mmol/litre or above that they are likely to have type 2 diabetes, and offer them a test to confirm this. [2015]

1.6.13 For women having an HbA1c test as the postnatal test:

  • Advise women with an HbA1c level below 39 mmol/mol (5.7%) that:
    • they have a low probability of having diabetes at the moment
    • they should continue to follow the lifestyle advice (including weight control, diet and exercise) given after the birth
    • they will need an annual test to check that their blood glucose levels are normal
    • they have a moderate risk of developing type 2 diabetes, and offer them advice and guidance in line with the NICE guideline on preventing type 2 diabetes (note that this guideline uses different risk thresholds, because it covers a different population).
  • Advise women with an HbA1c level between 39 mmol/mol and 47 mmol/mol (5.7% and 6.4%) that they are at high risk of developing type 2 diabetes, and offer them advice, guidance and interventions in line with the NICE guideline on preventing type 2 diabetes (note that this guideline uses different risk thresholds, because it covers a different population).
  • Advise women with an HbA1c level of 48 mmol/mol (6.5%) or above that they have type 2 diabetes, and refer them for further care. [2015]

1.6.14 Offer an annual HbA1c test to women with gestational diabetes who have a negative postnatal test for diabetes. [2015]

1.6.15 Offer women with gestational diabetes early self‑monitoring of blood glucose or an OGTT in future pregnancies. Offer a subsequent OGTT if the first OGTT results in early pregnancy are normal (see recommendation 1.2.6). [2008, amended 2015]

NICE guidelines, recommendations for postnatal care following GDM 1.6 Postnatal care

SIGN guidelines for Scotland

7.12 FOLLOW UP OF WOMEN WITH GDM
A diagnosis of GDM identifies women at increased risk of developing type 2 diabetes in future.
Rates of progression to type 2 diabetes in women with previous GDM vary widely (between 15 and 50% cumulative incidence at five years) and will be influenced by other risk factors such as ethnicity, obesity, and exercise. A Cochrane review concluded that diet combined with exercise or diet alone enhances weight loss post-partum. Both pharmacological and intensive lifestyle interventions reduce onset of type 2 diabetes in people with impaired glucose tolerance, including women with previous gestational diabetes.
• Women who have developed GDM should be given diet, weight control and exercise advice.
• Women who have developed GDM should be reminded of the need for pre-conception counselling and appropriate testing to detect progression to type 2 diabetes.
Where diabetes is not apparent immediately after delivery, glucose tolerance should be reassessed at least six weeks postpartum with a minimum of fasting glucose and with 75 g OGTT if clinically indicated. An annual assessment of glycaemia using fasting glucose or HbA1c should be carried out thereafter.

SIGN – Healthcare Improvement Scotland, Management of diabetes

Annual diabetes testing

Women diagnosed with gestational diabetes in pregnancy should be tested for diabetes every year. 

NICE – Diabetes in pregnancy, Quality standard [QS109]

Quality statement

Women diagnosed with gestational diabetes who have negative postnatal testing for diabetes after the birth are offered annual HbA1c testing. [2016, updated 2023]

NICE, Diabetes in pregnancy, Quality standard [QS109], January 2023​7​

Type 2 diabetes is when your body either does not produce enough insulin, or the body’s cells do not react to the insulin, causing insulin resistance.

Knowing the risk factor of being diagnosed with type 2 diabetes later in life is higher, it is advisable to look at dietary and lifestyle choices which could impact and lessen your chances of being diagnosed.

symptoms of diabetes infographic

Following gestational diabetes, some mothers are diagnosed with other types of diabetes such as Type 1, or MODY which may have been present but undetected before the pregnancy.

Increased risk of diabetes in the baby

Babies born to mothers who had gestational diabetes in pregnancy have a sixfold increase in the risk of developing diabetes, a higher risk of obesity (having a body mass index of more than 30) and cardiovascular problems later in life​1,8–10​.

Future pregnancies

After having gestational diabetes, there is an increased risk of having gestational diabetes in any future pregnancies​11​. For this reason, it is advisable to speak to your GP if you are planning another pregnancy or when you become pregnant. They may arrange for you to monitor your own blood glucose from the early stages.  Some hospitals will assume that you have gestational diabetes in a subsequent pregnancy and will treat you as such from the start.  Other hospitals will get you to perform an earlier GTT (glucose tolerance test), which is commonly around 16 weeks. Following a negative GTT, a repeat GTT is usually offered.

Research

  1. 1.
    DIABETES UK. DIABETES STATISTICS. Published 2023. Accessed February 24, 2023. https://www.diabetes.org.uk/professionals/position-statements-reports/statistics
  2. 2.
    Bellamy L, Casas JP, Hingorani AD, Williams D. Type 2 diabetes mellitus after gestational diabetes: a systematic review and meta-analysis. The Lancet. Published online May 2009:1773-1779. doi:10.1016/s0140-6736(09)60731-5
  3. 3.
    Diabetes in pregnancy: management from preconception to the postnatal period. NICE – National Institute for Health and Care Excellence. Published December 16, 2020. Accessed February 24, 2023. https://www.nice.org.uk/guidance/ng3
  4. 4.
    Kim C, Newton KM, Knopp RH. Gestational Diabetes and the Incidence of Type 2 Diabetes. Diabetes Care. Published online October 1, 2002:1862-1868. doi:10.2337/diacare.25.10.1862
  5. 5.
    NICE, Diabetes in pregnancy Quality standard [QS109]. Quality statement 4: Postnatal testing and referral. Published January 10, 2023. Accessed February 24, 2023. https://www.nice.org.uk/guidance/qs109/chapter/Quality-statement-4-Postnatal-testing-and-referral
  6. 6.
    World Health Organization. HEARTS D: diagnosis and management of type 2 diabetes. Published April 22, 2020. Accessed February 24, 2023. https://www.who.int/publications/i/item/who-ucn-ncd-20.1
  7. 7.
    NICE, Diabetes in pregnancy Quality standard [QS109]. Quality statement 5: Annual HbA1c tests. Published January 10, 2023. Accessed February 24, 2023. https://www.nice.org.uk/guidance/qs109/chapter/Quality-statement-5-Annual-HbA1c-tests
  8. 8.
    Vohr BR, Boney CM. Gestational diabetes: The forerunner for the development of maternal and childhood obesity and metabolic syndrome? The Journal of Maternal-Fetal & Neonatal Medicine. Published online January 2008:149-157. doi:10.1080/14767050801929430
  9. 9.
    Reece EA. The fetal and maternal consequences of gestational diabetes mellitus. The Journal of Maternal-Fetal & Neonatal Medicine. Published online February 2, 2010:199-203. doi:10.3109/14767050903550659
  10. 10.
    Holder T, Giannini C, Santoro N, et al. A low disposition index in adolescent offspring of mothers with gestational diabetes: a risk marker for the development of impaired glucose tolerance in youth. Diabetologia. Published online August 29, 2014:2413-2420. doi:10.1007/s00125-014-3345-2
  11. 11.
    Kim C. Maternal outcomes and follow-up after gestational diabetes mellitus. Diabet Med. Published online February 16, 2014:292-301. doi:10.1111/dme.12382