Diabetes Mellitus is a metabolic and chronic disease, which is identified by elevated blood glucose levels. These elevated blood glucose levels can result in developing macrovascular and microvascular complications (World Health Organization, 2023). The two main types of diabetes mellitus are type 1 and type 2, the most prevalent type is Type 2 Diabetes Mellitus (hereafter referred to as T2DM) (World Health Organization, 2023). Without insulin replacement in Type 1 Diabetes Mellitus (T1DM), death will occur within weeks or days (National Institute for Health and Care Excellence, 2022).
Diabetes mellitus and pregnancy
The National Institute for Health and Care Excellence (NICE) provides guidelines for managing preconception and diabetes mellitus. Under these guidelines, NICE advises providing women with diabetes mellitus with the requisite information, support and advice to mitigate the adverse risks to mother and foetus that are associated with diabetes mellitus and pregnancy (National Institute for Health and Care Excellence, 2020). These risks include; miscarriage, stillbirth, perinatal death, congenital malformations, neural tube defect, neonatal hypoglycaemia, blood glucose control affected by nausea and vomiting (National Institute for Health and Care Excellence, 2020). The infant may also be large for their gestational age, resulting in labour inductions, birth traumas, shoulder dystocia, caesarean section and instrumental deliveries (National Institute for Health and Care Excellence, 2020). Monitoring through an early ultrasound scan at approximately 7 weeks gestation is crucial (Guy's and St Thomas NHS Foundation Trust, 2022). The infant is also at risk of developing diabetes mellitus in the future (National Institute for Health and Care Excellence, 2020).
Informing women with diabetes mellitus on the risks of hyperglycaemia is recommended (National Institute for Health and Care Excellence, 2020). However, NICE also states informing women on the roles that exercise and diet have on diabetes mellitus and pregnancy. These risks persist post-partum (National Institute for Health and Care Excellence, 2020).
Monitoring blood levels
Haemoglobin A1C (HbA1c) is a combination of haemoglobin and glucose, which occurs when some glucose binds to the protein responsible for carrying oxygen in the red blood cells, known as haemoglobin (Lab Tests Online UK, 2021). As erythrocytes have a lifespan of 2-3 months, HbA1c reflects the average concentration of glucose within the bloodstream during this time (Lab Tests Online UK, 2021). HbA1c tests to monitor blood glucose levels, are recommended for women with diabetes mellitus that are planning a pregnancy (National Institute for Health and Care Excellence, 2020). The general practice nurse (GPN) can also offer blood glucose meters for self-monitoring blood glucose levels (National Institute for Health and Care Excellence, 2020). Monitoring blood glucose levels can be tailored to meet the patient's needs as women who require a more intense intervention can be advised to increase self-monitoring, particularly to be inclusive of fasting and pre-and post-meal levels (National Institute for Health and Care Excellence, 2020).
Also, offering a blood ketone monitor and strips if a woman has T1DM and planning a pregnancy is important (National Institute for Health and Care Excellence, 2020). If a GPN does distribute a blood ketone monitor, they must advise that the monitor is to test for ketonemia should the woman experience hyperglycaemia or during illness (National Institute for Health and Care Excellence, 2020). Blood ketones should be tested if experiencing an unexpected or unexplained blood glucose level above 14 mmol/l (Milton Keynes University Hospital NHS Foundation Trust, 2024). Patient awareness of diabetic ketoacidosis is crucial (Diabetes UK, 2024a). Seeking immediate medical advice for blood glucose levels above 14 mmol/l with a blood ketone level of above 1.5 mmol/l (Milton Keynes University Hospital NHS Foundation Trust, 2024)
Both monitoring blood glucose levels and preconception blood glucose targets can be tailored for individual needs (National Institute for Health and Care Excellence, 2020). The National Institute for Health and Care Excellence states that these targets should be agreed between the healthcare professional and the client, however healthcare professionals should take into consideration hypoglycaemia being a risk (National Institute for Health and Care Excellence, 2020). The general aim for HbA1c levels is less than 48 mmol/mol for women with diabetes mellitus that are planning a pregnancy (National Institute for Health and Care Excellence, 2020). It is also mentioned that this target is only an aim if the woman is capable of meeting it without experiencing hypoglycaemia. If hypoglycaemias are experienced, GPNs are to advise that any achievement towards the HbA1c target will reduce risks associated with hyperglycaemia occurring (National Institute for Health and Care Excellence, 2020)
Pregnancy is strongly discouraged if HbA1c levels exceed 86 mmol/mol due to associated risks (National Institute for Health and Care Excellence, 2020). The National Institute for Health and Care Excellence advice for strict glycaemic control to reduce the risks associated to mother and foetus are supported by a systematic review on preconception care (Lassi et al, 2014). This systematic review looked at screening and management of chronic diseases (Lassi et al, 2014). As well as the management of promoting psychological health, this systematic review supported strict blood glucose control during pregnancy. There was further support on the benefits to both mother and foetus if glycaemic control, diet adjustments and counselling were implemented during preconception (Lassi et al, 2014).
Preconceptual Counselling
Preconceptual counselling is advocated for women with diabetes mellitus (Yehuda, 2016). Preconception care is defined by the Centers for Disease Prevention and Control as consisting of a group of interventions that seek to recognise, as well as adapt risks associated with behavioural, medical and social aspects in a woman's pregnancy outcome and health through management and prevention (Yehuda, 2016). It is proposed that counselling as well as preconception risk assessments should be undertaken for women with diabetes mellitus that are of reproductive age, to improve pregnancy outcomes (Yehuda, 2016). Preconception care should consist of nutrition, immunisations, medical history, family and reproductive history, medications, assessment of risks associated with social conditions and family planning (Yehuda, 2016). Contraception options assessed routinely for women with diabetes mellitus that are of childbearing age is recommended (Yehuda, 2016). Women with diabetes mellitus are also recommended to take folic acid 5mg, three months prior to contraception withdrawal (Yehuda, 2016). Also to undergo medication reviews to manage any complications (Broughton & Douek, 2019).
These pre conceptual suggestions are also supported by NICE guidelines (National Institute for Health and Care Excellence, 2020). Healthcare professionals, such as GPNs should encourage women with diabetes mellitus that are planning a pregnancy to take prescribed folic acid 5mg a day, until 12 weeks of gestation to decrease the likelihood of neural tube defect occurring (National Institute for Health and Care Excellence, 2020). General practice nurses should advise contraception is used if HbA1c level is above 86 mmol/mol (National Institute for Health and Care Excellence, 2020). The Faculty of Sexual and Reproductive Healthcare UK medical eligibility criteria for contraceptive use is recommended by NICE to assess risk factors and cater to personal preference when choosing contraception (National Institute for Health and Care Excellence, 2020). Due to the risks associated with pregnancy and diabetes mellitus, NICE emphasises the importance of risk awareness (National Institute for Health and Care Excellence, 2020).
Smoking cessation should be offered as smoking in pregnancy increases the risk of premature labour, stillbirth and miscarriage (NHS England, 2022). Additionally, alcohol consumption must be avoided as it can increase the risk of foetal neural disorders and impaired growth (UNICEF Parenting, 2024).
During pregnancy susceptibility to food-borne illnesses increases, necessitating patient education on foods to avoid such as; raw meat, undercooked fish/seafood and unpasteurised milk (UNICEF Parenting, 2024). General practice nurses should offer weight management advice to women with diabetes that are planning a pregnancy and have a body mass index (BMI) above 27 kg/m2 (National Institute for Health and Care Excellence, 2020).
Medicine management
It is recommended that women who have T2DM begin metformin as either an alternative or as an adjunct to insulin during preconception and pregnancy (National Institute for Health and Care Excellence, 2020). However, it is advised that this is the potential of harm in relation to the benefits of the improved blood glucose levels. General practice nurses should also suspend women with T2DM that are intending to become pregnant from taking any other oral agents, such as gliclazide that are used to reduce blood glucose levels and use insulin instead (National Institute for Health and Care Excellence, 2020). This is because metformin, whilst crosses the placenta, does not pose any severe risk to the foetus, doesn't increase the risk of hypoglycaemias and has been found to improve patient satisfaction (Kalra et al, 2015).
Prior to conception, angiotensin-converting enzyme inhibitors (ACE inhibitors) such as ramipril, as well as angiotensin-II receptor antagonists such as candesartan, and statins are to be stopped (National Institute for Health and Care Excellence, 2020). Angiotensin-II receptor antagonists and ACE inhibitors may cause congenital anomalies, renal dysfunction, neonatal anuria and oligohydramnios (Medicines and Healthcare products Regulatory Agency, 2014). However, thiazide diuretics, nifedipine and labetalol are safe to use during pregnancy (Yale Medicine, 2024). Statins are deemed by early reports to be teratogenic (Karalis et al, 2016).
Due to the importance of frequent blood glucose monitoring, hybrid closed-loop systems, which must be used only under specialist care, and insulin pumps are recommended for women with T1DM that are pregnant or planning to conceive (Diabetes UK, 2024b). Pregnant women with T1DM may also be offered a continuous glucose monitor (CGM). As well as pregnant women with T2DM that are experiencing severe hypoglycaemias or have poorly controlled T2DM (Diabetes UK, 2024c). Therefore, GPNs must refer women with diabetes for pre-conception counselling at specialist diabetes and pregnancy clinics (Guy's and St Thomas' NHS Foundation Trust, 2022).
Renal and retinal assessments
Prior to becoming pregnant, GPNs are to advise women with diabetes mellitus regardless of which type to have renal and retinal assessments (National Institute for Health and Care Excellence, 2020). Pregnancy not only increases the risk of developing renal and retinal complications but can also worsen such existing complications (National Health Service, 2021). The assessments are to be offered during the first preconception appointment, unless the patient has had a retinal or renal assessment carried out within six months prior to attending their first preconception appointment (National Institute for Health and Care Excellence, 2020). General practice nurses are also advised to encourage women with diabetes mellitus that are planning a pregnancy, to keep their blood glucose levels stable until they have finished having their retinal assessment and completed any treatment for this (National Institute for Health and Care Excellence, 2020). Renal assessments are advised to include a measurement of albuminuria prior to suspending contraception (National Institute for Health and Care Excellence, 2020). Found in the blood, albumin is a protein that typically only passes into the urine in miniscule amounts when the kidneys are functionally properly. However, when changes occur to the kidneys such as due to diabetes mellitus, an abnormal concentration known as albuminuria occurs (Lab Tests Online UK, 2022). Unless receiving appropriate treatment, GPNs should refer women with diabetes mellitus to specialist renal services if their Urine Albumin to Creatinine Ratio (ACR) is 70mg/mmol or higher (GP Notebook, 2022).
Implementing changes in care
Whilst national guidelines highlight the importance of women of childbearing age receiving preconception care, the number of women with diabetes mellitus in the United Kingdom (UK) taking up such services remains low (Mortagy et al, 2010). A study to explore integrating care for women with diabetes mellitus in primary care revealed that the involvement of general practitioners in providing women with diabetes mellitus with preconception care, could be more effective (Mortagy et al, 2010). This study suggested that policy and organisational developments were required to provide general practitioners with support in providing preconceptual care for women with diabetes mellitus. (Mortagy et al, 2010). The study concluded that their findings highlighted how valuable an integrated approach is to be able to provide women with diabetes mellitus a favourable preparation for pregnancy, as well as for continuity of care (Mortagy et al, 2010). Whilst the suggestions in the conclusion were in reference to general practitioners, such suggestions can also be applied to GPNs providing preconception care to women with diabetes mellitus. The GPN will also be fulfilling the practice effectively aspect of the NMC Code of Conduct (NMC, 2018), by working alongside midwives in secondary care and being aware of any developments in policies.
A systematic review was conducted on digital and conventional health interventions for educating women with diabetes mellitus on preconception care. With the aim to recognise, outline and evaluate the methods that are currently used to provide preconception care education to women with diabetes mellitus (Nwolise, Carey and Shawe, 2016).
The results of the systematic review revealed consistent reports of improved outcomes for women receiving educational interventions from health care professionals or through eHealth (Nwolise, Carey and Shawe, 2016). Significant improvements were observed in HbA1c levels and knowledge, as well as their views on seeking preconception care. The results also reported a decline in adverse foetal outcomes, barriers and preterm deliveries (Nwolise, Carey and Shawe, 2016). The systematic review concluded that the impact of preconception care on women with diabetes mellitus was positive on their pregnancy outcomes (Nwolise, Carey and Shawe, 2016). However, the uptake of women with diabetes mellitus participating in preconception care has been reported as low (Mortagy et al, 2010). The review also noted that the applications being used to provide women with diabetes preconception care is still in the early stages (Nwolise, Carey and Shawe, 2016). However, recommendations for future research advocated the use of mobile phones in delivering preconception care, the results were so far promising (Nwolise, Carey and Shawe, 2016). Applying the suggestions of the review to practice, GPNs can advise women who require preconception care on suitable knowledgeable websites. This includes websites such as the planning for pregnancy tool on the Tommy's website that was developed in partnership with the National Health Service and Public Health England (Tommy's, 2022).
Conclusion
General practice nurses have already made an impact on improving preconception management in primary care; but through:
We can continue to further empower women with diabetes mellitus.