Diabetes and Pregnancy

Introduction

This clinical practice guideline addresses only type 1 and type 2 pre-conceptional diabetes. These are high-risk pregnancies and require joint care by specialized diabetologists, obstetricians, and neonatologists in close cooperation with other areas of specialization. The clinical practice guideline does not present the topic comprehensively but focuses on specifics.

Epidemiology

In 2022, there were 7963 cases of pregnancy with preexisting diabetes mellitus (type 1, type 2 diabetes). This corresponds to a relative frequency of 1.13%. The proportion of pregnant women with type 2 diabetes among all pregnant women with preexisting diabetes is estimated to be at least 10–30% in Germany.

Children of diabetic mothers have an average 1.5- to 3-fold increased risk of congenital malformations, prematurity, hypertrophy, respiratory failure, plexus palsy, and asphyxia. The risk of stillbirth and death in the first seven days of life is increased in cases of pre-pregnancy diabetes. The most common complication by far in newborns of diabetic mothers is postnatal hypoglycaemia, which is approximately 200- to 400-fold more common among these babies than in those of nondiabetic mothers.

Pre-conception care

Inadequately treated diabetes mellitus at conception – both in terms of metabolic control and the treatment of concomitant diseases – carries an increased risk of congenital malformations, intrauterine foetal death, pregnancy complications, but also the risk of progression of diabetes-associated secondary complications, such as retinopathy or nephropathy and cardiovascular pre-existing conditions.

In a UK cohort study of 747 women with type 1 diabetes, 39% of pregnancies were unplanned. Women with unplanned vs. planned pregnancies were younger, more likely to be smokers, had lower social status and education levels, and were less likely to be in pre-conception care. Unplanned vs. planned pregnancy showed higher HbA1c levels both pre-conception and during pregnancy. Neonates in unplanned pregnancy more often showed birth weight<5th percentile and more often required both treatment in a neonatal intensive care unit and hospitalization for more than 10 days. Women with pre-conceptional treatment were less likely to show intrauterine amniotic death and preterm birth.

Hyperglycaemia

Data supports an association between elevated maternal HbA1c/hyperglycaemia pre-conceptionally and during embryogenesis, and an increased rate of malformations. Congenital malformations are 2 to 3 times less frequent with sufficient therapy pre-conception. Comprehensive diabetic-specific counselling regarding contraception, pregnancy planning and pre-conceptional therapy targets is a crucial preventative measure, which should regularly be focused on in fertile women. Contraception should be continued until the HbA1c therapy target is reached.

Concomitant diseases

Diabetes-associated concomitant diseases are independent risk factors for pregnancy complications and an adverse foetal outcome.

Obesity

Maternal obesity is an independent maternal and foetal risk factor. Women with a body mass index greater than 25 kg/m² have an increased risk of miscarriage and perinatal mortality and as of a BMI of 30 kg/m² also have a lower chance of becoming pregnant [2] [3] [4] [5]. A meta-analysis demonstrated an association between the BMI of pregnant women and the risk of preeclampsia. In cases of obesity, pre-conceptional lifestyle intervention should be sought. A lifestyle with increased exercise and adequate nutrition pre-conception shows positive effects on pregnancy and delivery/birth [6].

Autoimmune diseases

Population studies show that approximately one in three people with type 1 diabetes has another autoimmune disease, with autoimmune thyreopathy being the most common secondary disease [7] [8] [9] [10].

Metabolic targets

Pre-conceptional blood glucose targets

Numerous studies have demonstrated an association between pre-conceptional HbA1c levels and the risk of embryonic malformations and other adverse foetal and maternal events [11] [12] [13] [14] [15]. The risk is only slightly higher than that of the general population at HbA1c levels in the near-normal range but increases linearly with higher HbA1c levels. Accordingly, an HbA1c value<7.0% should be targeted pre-conception. If there is a tendency to hypoglycaemia or an unstable metabolic situation, the lowest value that is safe for the mother should be targeted. The use of a continuous glucose monitoring (CGM) system should also be considered, although a randomised trial failed to show an advantage of tissue glucose measurement across all pregnant women with type 1 diabetes in pre-conception preparation [16]. In some patients or situations with an unstable metabolic situation, such systems may nevertheless present a relevant advantage.

Blood glucose targets during pregnancy

A clear correlation between higher blood glucose levels and unfavourable foetal and maternal events has also been shown for blood glucose levels during pregnancy [12] [17] [18]. Furthermore, superiority of treatment using CGM during pregnancy over conventional blood glucose measurement has been demonstrated [16]. Tissue glucose measurement was accompanied by slightly lower average blood glucose values, which was likely responsible for the better results observed in this group. Accordingly, this study supports the goal of achieving blood glucose levels as close to normal as possible during pregnancy. During the course of pregnancy, an HbA1c value in the upper normal range – while taking the risk of hypoglycaemia into account – should be aimed for. Severe maternal hypoglycaemia is, of course, also dangerous during pregnancy and must be avoided. In contrast, a negative influence of mild maternal hypoglycaemia on foetal development has not been proven in humans [19] [20] [21] [22].

Counselling for patients wanting to have children

Abortion and risk of malformation

Women with diabetes have an increased risk of early spontaneous abortion [23], which correlates with the quality of periconceptional metabolic control [24] [25] [26]. Similarly, malformations occur more frequently in foetuses of diabetic pregnant women in correlation with the quality of metabolic control at the time of conception. The risk is 1.7- to 11-fold (on average about 4-fold) higher than that of metabolically-healthy women [27] [28].

A meta-analysis concludes a 2.4-fold increased relative risk for relevant congenital malformations in maternal pre-conceptional diabetes [29]. In absolute terms, the risk in studies ranges from 5.0 to 9.8%. However, an increased malformation rate is no longer found for type 1 diabetes in all studies, which is seen as a reflection of better metabolic control periconceptually and during pregnancy [30]. The risk of foetal malformations for pregnant women with known type 2 diabetes is not lower than that of women with type 1 diabetes [27] [31]. In particular, inadequate pre-conception care may also decisively contribute to the high risk in mothers with type 2 diabetes [31]. Since periconceptional metabolic control is decisive in the malformation rate, this rate is lower in planned pregnancies than in unplanned pregnancies [32].

The spectrum of malformations associated with maternal diabetes (type 1 diabetes/type 2 diabetes) includes, in particular, congenital heart defects (2.3–4%, approximately 4-fold compared to women without diabetes), neural tube defects (1.2–2.5%, 2- to 3-fold increased), skeletal anomalies, omphaloceles, malformations of the urinary tract, and biliary atresia with splenic anomalies [33] [34] [35] [36]. The risk of a congenital heart defect ranges from 2.6 to 6.5% for the offspring of patients with type 2 diabetes [37].

Multiple malformations are often present [35] [37] without a clear phenotype of diabetic embryopathy being definable. Previously, it was assumed that the risk of numerical chromosomal aberrations was not increased by preexisting maternal diabetes mellitus, but according to new findings from a large population-based study from the USA in 2020, there is an approximately 40% increased risk of Down syndrome and chromosomal disorders [38] [39]. This new finding, which is contrary to previous data, must first be confirmed by further studies. The foetal malformation rate in women with diabetes seems to be reduced by periconceptional administration of water-soluble vitamins, especially folic acid [40].

Risk of offspring developing type 1 diabetes

Offspring of women with type 1 diabetes also have an approximate 2–5% lifetime risk of developing type 1 diabetes.

Insulin therapy

Choice of insulin preparation

Analogue insulins have become the insulins of choice. Due to their product characteristics, short-acting analogues lead to faster absorption and long-acting analogues to longer efficacy and more consistent absorption than human insulins. In a meta-analysis of randomised trials of short-acting insulin analogues, no differences were found in HbA1c levels in pregnant women with type 1 diabetes compared with human insulin. For the short-acting insulin analogues aspart and lispro, new formulations are available with faster absorption and onset of action and a shorter duration of action profile. Both FIASP and Lyumjev are approved for use in pregnancy. Insulin glulisine currently has insufficient data for pregnancy and should not be administered in pregnancy.

Continuous glucose monitoring

A first large randomised controlled trial (n=325) of real-time (rt) CGM in pregnancy [16] showed significant benefits in neonatal outcomes for rtCGM use in pregnant women with type 1 diabetes (neonatal hypoglycaemia, length of intensive care unit (ICU) stay, birth weight, length of hospital stay). Glycaemic testing provided significant benefits in time-in-range (68% vs. 61%), rate of hyperglycaemia (27% vs. 32%), and HbA1c (−0.19%); small, not significant benefits in hypoglycaemia frequency and severe hypoglycaemia (18 CGM and 21 controls).

The AiDAPT study, published in 2023, shows the superiority of a hybrid closed-loop system (HCLS) over the use of a CGM system alone or in combination with insulin pump therapy in terms of glycaemic control during pregnancy: The time in the target range was 10.5% higher – which corresponds to about 2.5 hours more time in the target range per day – and the HbA1c value was 0.3% lower, without an increase in hypoglycaemia frequency [1]. In this HCLS, an insulin pump and a CGM system are connected via the CamAPS FX app installed on the mobile phone, which controls the insulin delivery via an algorithm and depends on the continuously measured glucose values. In the HCLS group, hypertension control was better, and weight gain was 3.5 kg lower in the 124 mothers studied, as was the number of large-for-gestational-age (LGA) babies. The outcome data regarding complications cannot yet be conclusively assessed due to the relatively low number of cases. Mothers rated the technology positively, and an accompanying study showed reduced stress and anxiety levels. The data from the AiDAPT study are essentially confirmed by the data from the CRISTAL study published in 2024. It is to be expected that the HCLS will be used as early as the baby planning stages and not only from the end of the first trimester, as in the AiDAPT study thus improving the results for mother and child even more significantly. In view of the available studies, there are indications that HCLS will prove to be the optimal therapy for pregnant women with type 1 diabetes in the future.

Hypoglycaemias

Severe hypoglycaemias in pregnant women with the need for glucose or glucagon administration must be avoided primarily with regard to the mother. Pre-conceptional (overly) strict blood glucose control can result in hypoglycaemic adrenergic warning signs increasingly being suppressed and eventually disappearing due to insufficient hormonal counter-regulation. Low target blood glucose levels during pregnancy may further exacerbate hypoglycaemic rates in pregnant women at risk, which in turn worsens hypoglycaemia perception. Very low mean blood glucose levels increase the risk of preterm birth compared with intermediate control levels (odds ratio [OR] 3.0; [41]). Adverse foetal effects from single, severe hypoglycaemias have not been reported; however, follow-up of children regarding their psychomotor development is lacking. The risk should be considered of foetal growth restriction with persistent very low blood glucose control below the target range.

Complications in pregnancy due to diabetes-associated concomitant diseases

The presence of diabetic microangiopathy in early pregnancy increases the risk of complications during pregnancy. A meta-analysis in type 1 diabetes shows an increased risk of preeclampsia compared with diabetic women without microangiopathy (OR 3.0 in the presence of diabetic retinopathy and 7.2 in the presence of diabetic nephropathy). The presence of nephropathy is associated with an increased risk of preterm delivery (PTD) (OR 4.1) and small for gestational age (SGA) (OR 6.2), and the presence of retinopathy increases the risk of PTD (OR 1.6) [42]

Pre-existing type 2 diabetes at the time of planning pregnancy and in pregnancy

In principle, type 2 diabetes mellitus is associated with the same foetal risks as type 1 diabetes mellitus. In addition to diabetes mellitus as a risk factor for pregnancy, women with type 2 diabetes mellitus have a higher risk profile compared with women with type 1 diabetes mellitus in terms of age>30 years, a high obesity prevalence, chronic hypertension, and asymptomatic concomitant vascular disease and also ethnicity [35] [43] [44] [45] [46] [47] [48]. Increasingly, obesity and/or other diabetes risk factors are affecting women of reproductive age [49]. In such cases, diabetes screening is recommended already at the time of planning pregnancy and definitely in early pregnancy to exclude diabetes in pregnancy (DIP)/type 2 diabetes [50]. In the DALI study, 0.5% of European obese pregnant women already had DIP at the 15th week of gestation [51].

Pre-conception care

Unplanned pregnancy, lack of near-normal metabolic control or even unawareness of metabolic control pre-conception, and the too-late initial consultation at a centre all play a crucial role in congenital malformations and increased perinatal mortality and morbidity [52]. However, up to 95% of women with type 2 diabetes mellitus become pregnant unplanned. Up to 76% are not under diabetological care either pre-conceptionally or during the period of organogenesis, and up to 2% did not have a documented HbA1c value in the last six months pre-conception. Pre-conceptional folic acid supplementation occurs even less frequently than in type 1 diabetes. A switch from oral antidiabetic drugs to an intensive form of insulin therapy, as well as diabetological supplementary care should already take place at the planning stages of pregnancy, i. e. always pre-conception [53] [54]. In the case of suboptimal metabolic control, women must be informed about the possible risk of congenital malformation.

Oral antidiabetics

Data on the use of oral antidiabetic drugs during pregnancy for type 2 diabetes is sparse. Conception while on oral antidiabetic drugs (OAD) is not an indication for terminating a pregnancy. Sulfonylurea preparations and metformin are, however, placenta-permeable and potential long-term effects in the offspring are insufficiently documented [55] [56]. Study data is available mainly on glibenclamide and metformin in pregnancy, whereas publications on Dipeptidylpeptidase-4 (DPP4) or sodium-glucose linked transporter 2 (SGLT-2) inhibitors is still lacking. Glibenclamide therapy showed higher maternal weight gain compared to metformin in pregnancy and also more frequent macrosomia and neonatal hypoglycaemia compared to metformin or insulin [57]. Neonates from glibenclamide-treated pregnancies have a higher risk of birth complications [58].

In very insulin-resistant and severely overweight women with type 2 diabetes, therapy with metformin may also be considered in addition to insulin to improve metabolism and attenuate insulin resistance [59]. Vitamin B12 monitoring is recommended for long-term use of metformin together with pregnancy [56].

Although there are now several studies of metformin compared or in addition to insulin in the treatment of type 2 diabetes in pregnancy that at least confirm fewer hypoglycaemias in pregnancy and the safety of the medication, the quality and case size of the studies are still insufficient for evidence-based recommendations. A small parallel group study from Pakistan, which included women with type 2 diabetes from the 1st trimester onward with metformin therapy alone versus insulin administration alone versus a combination of metformin and insulin showed that 85% of women required additional insulin and that metformin patients gained less weight, were less likely to develop gestational hypertension and neonatal hypoglycaemia, and neonates required intensive care unit care less often, although they were more often SGA [60]. A Cochrane meta-analysis of 3 RCTs of 241 pre-conceptional type 2 diabetes or impaired glucose tolerance (IGT) and post-gestational diabetes (GDM) pregnancies, all of whom had type 2 diabetes in pregnancy, found that metformin led to a potential reduction in rates of C-section, gestational hypertension, and neonatal hypoglycaemia compared with insulin [61]. Rates of preeclampsia, preterm birth, and large for gestational age (LGA) were not different. However, the quality of evidence was low. Possible long-term effects of metformin therapy in pregnancy on later foetal development cannot be excluded [56] and currently argue for individualized mindful use: in the MIG TOFU study, children whose mothers received metformin therapy showed increased subcutaneous fat mass and, after 7 to 9 years, higher body weight and abdominal circumference compared with the insulin group [62] [63]. A follow-up of 4-year-old children of women with polycystic ovarian syndrome (PCOS) on metformin therapy during pregnancy showed a significantly increased risk of excess weight/obesity compared with placebo [64]. Currently, metformin therapy in pregnant women with type 2 diabetes is being studied in 2 trials (MiTy and MOMPOD) [65]. In the MiTy trial, 502 women with type 2 diabetes and insulin therapy were randomised to additional metformin (2×1 g) or placebo between 6th and 22nd weeks of gestation [66]. While the primary neonatal composite outcome was not different and some benefits such as better glycaemic control with lower insulin requirements and fewer LGA infants and C-sections were determined with metformin, growth retardation (SGA infants) was seen almost twice as often with metformin (13 vs. 7%). Similarly, a recent meta-analysis found that metformin exposure in utero was associated with smaller neonates and accelerated postnatal growth [67].

If women with type 2 diabetes who are already pregnant are taking metformin and these women have normoglycaemic metabolic control, they can be reassured in the absence of evidence of a teratogenic effect of metformin. However, once pregnancy has been determined, switching to insulin therapy is required [68]. In general, for OADs, switching to insulin therapy before conceiving is indicated because of diaplacental transfer, insufficient evidence for successful therapy, insufficient data regarding long-term consequences for the baby, and the contraindication of OAD in Germany for therapy of type 2 diabetes during pregnancy. Women with type 2 diabetes who wish to have children should therefore be switched to insulin therapy before conceiving. Appropriate training of patients for self-adjustment of the insulin dose and information about possible risks, as well as the expected metabolic changes during pregnancy, should be provided by the physicians in charge of pregnancy planning/desire to have children.

The European Medicines Agency (EMA) approved metformin (Glucophage) 2022 for treatment in preexisting diabetes: Thus, treatment with metformin can be continued in individual cases of marked insulin resistance in addition to insulin therapy. With regard to insulin therapy before and during pregnancy as well as postpartum, the same criteria and recommendations apply as for type 1 diabetes.

Lifestyle

Accompanying drug therapy in type 2 diabetes and pregnancy, the lifestyle recommendations generally applicable to diabetes, as well as the general recommendations for weight gain in pregnancy dependent on pre-conceptional weight, should also be followed. An individualized treatment plan consisting of lifestyle modification with dietary recommendations, exercise, supported and monitored by blood glucose self-monitoring, must be created. The dietary plan must be based on body weight and physical activity, consisting of about 40–50% carbohydrates (fibre about 30 g/day), 30–35% mainly vegetable fat and 20% protein, as well as sufficient minerals and vitamins (iron, folic acid, vitamin D, calcium, vitamin B, magnesium, iodine). Unfortunately, data is lacking for optimal specific caloric intake in pregnant women with type 2 diabetes, so reference must be made to general dietary reference values. In any case, fast-absorbing carbohydrates should be avoided. A meta-analysis on low glycaemic index diets in pregnancy showed lower fasting blood glucose levels and LGA rates with this dietary plan [69]. The Endocrine Society recommends caloric restriction by about one-third in obesity; so that no significant weight reduction (up to a maximum of 5 kg) or catabolism occurs. Daily intake should be at least 1600 kcal [70]. Data for optimal weight gain versus weight maintenance in women with body mass index (BMI) > 35 kg/m² is lacking [65]. Body weight must be documented by the patient at each follow-up visit and on their own every week. Evidence for specific dietary recommendations for pregnant women with type 2 diabetes is low, and randomised controlled trials of different dietary approaches are not available. A pilot study from Denmark, which also included 43 women with type 2 diabetes, highlights the possibility of using special apps such as “Schwanger mit Diabetes” (Pregnant with Diabetes) and the information needs of those affected, especially for topics such as diet and carbohydrates [71].

Evidence-based recommendations for physical activity in pregnant women with type 2 diabetes are lacking, and a planned systematic Cochrane review could not be performed due to the lack of available randomized controlled trials (RCTs) as sources [72]. Medical societies recommend regular moderate physical activity (at least 150 min per week) integrated into everyday life as part of the therapeutic concept in unproblematic pregnancies [72]. The types of sport must be compatible with pregnancy and adapted to the individual training status (no contact sports or martial arts, or sports with a high risk of falling or injury).

Obstetric management

Type of birth

In perinatal statistics, the rate of C-sections is still significantly increased in women with diabetes compared to the general population. While the C-section rate is about 30% in Germany, the C-section rates in women with diabetes are still twice as high. Infantile macrosomia per se or maternal retinopathy should no longer be a primary indication for a C-section, [73]. However, delivery by vacuum extraction or using forceps to facilitate the pushing phase may be considered if laser therapy was performed less than 6 weeks ago for actively proliferative retinopathy. The indication for secondary C-section in case of obstructed labour or abnormal cardiotocography (CTG), possibly in combination with borderline findings in foetal blood analysis, should be given generously. Because of the increased oxygen demand of foetuses with hyperinsulinism and diabetic fetopathy, there is more risk of subpartum asphyxia.

Metabolic control during labour

Evidence-based findings on how to approach the intrapartum are not available. Therefore, the setting targets are based on the targets applicable during pregnancy and take into account that even short-term hyperglycaemia of the mother can lead to increased insulin secretion in foetuses with an increased risk of postnatal hypoglycaemia. Therefore, during induction and delivery, blood glucose levels between 90 and 126 mg/dl (5.0–7.0 mmol/l) should be targeted. It should be noted that maternal hypoglycaemia can lead to a decrease in contractions.

With the onset of labour, insulin requirements drop rapidly to 50%. The pregnant woman should be informed about this in advance and as well about the appropriate measures to take at the onset of labour in the home environment and if being induced. In the case of pump therapy, she should be able to reduce the basal rate to 50%. After administration of basal insulin in the evening, blood glucose should be checked, and a supply of carbohydrates given at the onset of labour at night.

If a C-section is planned, the usual amount of basal insulin for the night should be injected the evening, possibly reduced to 75% if fasting blood glucose values tend to be low. Insulin pumps can be attached to the upper arm and continue to run at a 50% of the basal rate at the onset of a C-section.

When being induced, 50% of the basal insulin of the day should be injected in the morning with intensified insulin therapy. Blood glucose should be monitored in the short term and corrected with rapid-acting insulin. With insulin pump therapy, the basal rate should be left until the onset of contractions and, from the onset of regular contractions, lowered to 50% of the previous insulin dose.

During labour, blood glucose should be monitored every hour [74]. Immediate consequences must be drawn from the results. The obstetric team should be responsible for managing metabolism intrapartum and there should be an in-clinic, binding standard to guide the staff. In this context, it is also important that the pregnant woman is instructed from the diabetes side, in detail, in preparation for birth with regard to the importance of keeping the glucose values stable in the target range.

After the placenta is delivered, insulin requirements drop abruptly and there is an increased risk of hypoglycaemia. Insulin delivery must therefore be adapted at shorter intervals. To avoid catabolism and ketoacidosis, the insulin dose is continued at a low level (approx. 30–50% of the pre-birth dose) and continuously adjusted to the current blood glucose values.

The following checklist summarises important points in care (especially in the case of pre-existing type 1 diabetes) [Table 1].

Table 1 Checklist for care before and during pregnancy.

Point in Time	Necessary measures
Planning phase	Consultation with a diabetologist and gynaecologist Analyse accompanying risks: Retinopathy (referral to an ophthalmologist) Nephropathy (urinary albumin, serum creatinine, ACR, GFR) Neuropathy (medical history and clinical examination) Analyse macrovascular risk Excess weight/obesity: lifestyle intervention, 5%/10% weight reduction Comprehensive advice on nutrition and lifestyle Meal planning, correction of malnutrition, caffeine intake, safe food preparation Regular moderate exercise, sufficient sleep Check training status, instruct relatives in glucagon set/spray Optimise metabolism (HbA1c<7%) for at least 3 months, then stop contraception Offer/begin CGM If necessary: change insulin, switch to CSII, or switch to HCLS Prescribe at least 0.4 mg folic acid/day (0.8 mg/day for obesity), provide information on a folate-rich diet Prescribe iodide 100–200 μg/day (also for Hashimotoʼs thyroiditis), recommend iodized salt, nutritional counselling Thyroid: anti-TPO antibody & TSH screening Change high blood pressure therapy (swap ACE inhibitors/AT-1 antagonists for alpha-methyldopa) Discontinue statins, bempedoic acid, PCSK9 inhibitors, fibrate, and niacin
When pregnancy is diagnosed	Consultation with a diabetologist and gynaecologist Information about blood glucose target values Caveat: Risk of hypoglycaemia is 3–5 times higher in the 1st trimester Ophthalmological examination (if did not happen pre-conceptionally); with normal findings, follow-up at approx. 28th week of gestation, otherwise follow-ups in consultation with the ophthalmologist Albumin/creatine ratio screening, then at the beginning of each trimester
8–12 weeks of gestation	Ultrasound – check the intactness/location/gestational age
11–14 weeks of gestation	Ultrasound – early detailed ultrasound; optionally perform nuchal translucency measurement
From 16 weeks of gestation	Adjust insulin dose closely as demand increases, usually the insulin requirement increases by 50–100%
19–22 weeks of gestation	Differentiated organ diagnostics (LEVEL DEGUM II)
From 24 weeks of gestation	Biometrics every 2–4 weeks
From 32 weeks of gestation	CTG, on a case-by-case basis
32 weeks of gestation	Contact the perinatal centre (minimum LEVEL 2)
39 weeks of gestation	Estimate birth weight (>4500 g – discuss primary C-section;>4250 g – clarification of shoulder dystocia risk)
Premature labour	Inpatient admission, tocolysis oral administration: nifedipine (off-label), atosiban IV (therapy of choice)
Imminent premature birth	Strict indications: if necessary, foetal lung maturity induction with 2×12 mg betamethasone over 24 h, adjust insulin dose (+20–40%)
Gestational hypertension	High blood pressure therapy as of 140/90 mmHg Target value 135/85 mmHg Proper monitoring
Preeclampsia ASA	Proper monitoring Every patient should be advised about the administration of ASA. The administration of aspirin can also be indicated for preventing preeclampsia in women with diabetes in a risk-adapted manner via preeclampsia screening, or a general recommendation can be made. However, in the presence of both diabetes and nephropathy, ASA should be recommended to all pregnant women. If women with diabetes are given aspirin to prevent preeclampsia, it should be started before 16+0 weeks of gestation, continued at 150 mg/day until 35+0 weeks of gestation, and then discontinued.
Maternity clinic	Timely registration (at the latest at 36 weeks of gestation) perinatal centre LEVEL 2 or LEVEL 1 Instruction in collecting colostrum by midwife
Birth	Spontaneous birth is targeted; once contractions begin, cease injections of long-acting insulin, continue to use the pump (reduce basal rate to 50%). Blood glucose target value: 90–126 mg/dl.
Inducing labour	Once the calculated delivery date is exceeded
C-section	Primary and secondary C-sections only for obstetric indications
Child	Readiness for respiratory support (O2, CPAP) First nursing within 30 minutes First blood glucose measurement after 2 to 3 hours of life (see AWMF Guideline 024/006)
Breastfeeding	Recommended for 6–12 months, support in all aspects, if necessary with a lactation consultant
Child with a (genetic) diabetes risk	Consultation on the risk of type 1 diabetes in the child, possibly participation in screening/prevention studies
Documentation	Document basic data on diabetes and data on the course of pregnancy/birth/newborn, (if necessary, participation in the GestDiab register)

ACR, albumin-creatinine ratio; GFR, glomerular filtration rate; CGM, continuous glucose monitoring; CSII, continuous subcutaneous insulin infusion; HCLS, hybrid closed loop system; anti-TPO antibody, anti-thyroid peroxidase antibodies; TSH, thyroid stimulating hormone; ACE, angiotensin-converting enzyme; AT-1, Angiotensin-1; PCSK9, proprotein convertase subtilisin/kexin type 9; SSW, week of gestation; DEGUM Deutsche Gesellschaft für Ultraschall in der Medizin (German Society for Ultrasound in Medicine); CTG, cardiotocography; ASA, acetylsalicylic acid; CPAP, continuous positive airway pressure.

German Diabetes Association: Clinical Practice Guidelines

This is a translation of the DDG clinical practice guideline

published in Diabetologie 2024; 19 (Suppl 2): S203–S213.

DOI: 10.1055/a-2312-0352

Conflicts of interest

Lecture fees and/or consulting services: M. Hummel – Astra Zeneca, Boehringer-Ingelheim, Dexcom, Lilly, MSD, Novo Nordisk, Sanofi. M. Füchtenbusch – Abbott, Astra Zeneca, Berlin Chemie, Boehringer, Glaxo Smith Kline, Lilly, Novo Nordisk, Sanofi. C. Bührer – Chiesi, Nestlé. W. Battefeld – Berlin Chemie, Lilly, Novo Nordisk. T. Groten – Novo Nordisk, JenaPharm. T. Haak – Abbott, AstraZeneca, MSD, Roche. F. Kainer – GE Canon. A. Kautzky-Willer – Novo Nordisk, Lilly, Boehringer Ingelheim, AstraZeneca, Sanofi, Amgen, Novartis. T. Meissner – Lilly, Novo Nordisk. C. Nagel-Reupner – Amgen, Boehringer, Novo Nordisk, MSD, Lilly. U. Schäfer-Graf – Novo Nordik, Sanofi, Berlin-Chemie. T. Siegmund – Abbott, Astra, Berlin Chemie, Boehringer, Lilly, Medronic, MSD, Novo Nordisk, Roche, Sanofi.

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Publication History

Article published online:
06 May 2025