National Pregnancy in Diabetes Audit 2021 and 2022 (01 January 2021 to 31 December 2022)

One in two babies born to women with pre-existing diabetes in pregnancy have complications related to maternal glucose. The most serious pregnancy complications are congenital anomalies or birth defects (e.g. structural heart problems, spina bifida), stillbirths and neonatal deaths (babies that die at birth or in the first 28 days of life), known as perinatal or baby deaths. These serious adverse outcomes affect up to 1 in 10 pregnancies complicated by diabetes.

• The risks are lowest in women who achieve the National Institute for Health and Care Excellence (NICE) recommended HbA1c target of <48mmol/mol at conception and during the first 6 to 7 weeks of pregnancy, which is often before women are seen in maternity clinics.
• Serious adverse outcomes occur more frequently in women with unplanned pregnancies, who enter pregnancy with above target HbA1c levels, often without having had high dose (5mg/day) folic acid and sometimes taking potentially harmful medications.
• Baby deaths are increased in women with higher HbA1c levels, but babies are also sensitive to small changes in glucose levels during the second and third trimesters, so improving maternal glucose throughout pregnancy substantially reduces the risk of baby deaths.
• The less serious but more common diabetes pregnancy complications include large birthweight babies (meaning babies that weigh more than 90% of all newborns), premature births (babies who are delivered before 37 weeks gestation) and babies that are admitted to neonatal care units, which separates mothers and babies, interrupting mother-baby bonding, and infant feeding. These admissions are stressful for women and their families and extremely costly for the NHS.
• Data from the 2019 and 2020 NPID audit confirmed that the risks of baby deaths, large birthweight babies, preterm births and neonatal care admissions were all reduced in mothers who achieved a pregnancy HbA1c target of <43mmol/mol after 24 weeks gestation. It also demonstrated rising rates of preterm births and large for gestational age babies over the preceding 7 years.

The purpose of the NPID Audit is to report on the demographics, patterns of care and pregnancy outcomes for women with diabetes in England and Wales, and to provide services with information to help improve the quality of care before and during diabetes pregnancies. It measures the effectiveness of diabetes pregnancy healthcare against NICE Clinical Guidelines and NICE Quality Standards. NICE recommends 5mg/day folic acid supplementation for 3 months pre-pregnancy and avoidance of potentially harmful medications. NICE guidelines also recommend targets for pre-pregnancy and antenatal glucose control; and since December 2020 NICE have recommended that women with type 1 diabetes are offered continuous glucose monitoring (CGM) to help them meet their pregnancy glucose targets. The guideline recommendations are based on strong evidence that use of CGM technology improves maternal glucose and reduces obstetric and neonatal complications⁴.

The cohort consists of pregnancies in women with pre-existing type 1 and early-onset type 2 diabetes. There were a small number of pregnancies in women with other forms of diabetes which are not included in this short report but were included in wider analysis. Specialist multi-disciplinary maternity diabetes clinics submit individual records for pregnancies in women with pre-existing diabetes. These data are linked to data from the National Diabetes Audit (NDA), maternal inpatient admission records in Hospital Episode Statistics (HES), Patient Episode Database for Wales (PEDW) and to neonatal care admissions collected via the National Neonatal Research Database (NNRD). 

This NPID report focuses on NICE guidance² and Quality Standards¹ for the care of diabetes in pregnancy. NICE guidelines emphasise the importance of planning for pregnancy from adolescence for women with diabetes, as part of diabetes education. It advises that women with diabetes use contraception and have monthly measurement of HbA1c, aiming to reach the pregnancy glucose target of HbA1c <48mmol/mol. This is in addition to taking folic acid (5mg/day), and avoiding medications potentially harmful to the foetus or pregnancy (e.g. angiotensin‑converting enzyme inhibitors, angiotensin‑II receptor antagonists, and statins that are not approved for use during pregnancy). Advice on how to lose weight should be offered to those with a body mass index (BMI) above 27 kg/m². All pregnant women should be offered immediate contact with a joint diabetes maternity clinic, as soon as possible after confirmation of pregnancy.

Since December 2020, real-time continuous glucose monitoring technology should have been offered to all pregnant women with type 1 diabetes to help them meet recommended pregnancy glucose targets of below 5.3mmol/litre (fasting), below 7.8mmol/litre (1 hour after meals) and below 6.7mmol/litre (2 hours after meals). Continuous glucose monitoring should also be considered for women with type 2 diabetes who are on insulin therapy if they have problematic severe hypoglycaemia or unstable blood glucose levels.

There were more pregnancies recorded in this audit period (2021 and 2022) than in any other since the audit began (2014 to 2020)

Table 1: Summary of numbers of women, pregnancies and outcomes in 2021 and 2022^*

^*Throughout the report disclosure control has been applied to mitigate the risk of patient identification. Zeros are reported, and all numbers are rounded to the nearest 5, unless the number is 1 to 7, in which case it is rounded to 5. This allows for more granular data to be made available. Rounded numbers are used to calculate percentages therefore numbers may not sum as expected. Percentages are not calculated where the rounded denominator is 20 or less, and where numbers are small percentages are volatile and should be treated with caution.

^** Pregnancy outcomes are defined as the number of babies, including twins and adverse outcomes (such as miscarriages and stillbirths), which were recorded in the audit.

For this summary report, the detailed analysis spreadsheet 'NPID detailed analysis 2021 and 2022' can be found on the overview page.