Neonatal hypoglycaemia and the infant of a diabetic mother

• Neonatal hypoglycaemia is the commonest metabolic problem of the newborn and the leading reason well term infants are admitted to neonatal units. It is usually a problem of adaptation in the first hours to days after birth, not of a broken gland.
• In an infant of a mother with diabetes, fetal insulin stays high after delivery, so glucose falls while insulin keeps driving it down. About 5 to 27% of these infants become hypoglycaemic.
• There is no single agreed cut-off. Each major guideline uses a slightly different threshold, and the safest plan is to use the guideline your unit has adopted and to treat any infant with symptoms.
• Feed early, keep warm, screen the at-risk infant, and escalate early: severe (under 1.0 mmol/L at any time), persistent, or symptomatic hypoglycaemia need urgent review. ^[2]
• Most transitional hypoglycaemia resolves within 72 hours. Hypoglycaemia that persists beyond about 48 hours, or needs large amounts of glucose, points to hyperinsulinaemia or another persistent disorder and needs a full endocrine work-up.

By the end of this page you should be able to:

1. Define neonatal hypoglycaemia and distinguish transitional (adaptive) from persistent hypoglycaemia.
2. Explain why an infant of a diabetic mother becomes hypoglycaemic, and what else clinically follows from maternal hyperglycaemia.
3. List the infants who should be screened, when and how often, and how blood glucose is measured reliably.
4. Compare the operational thresholds used by the AAP, PES, BAPM and StatPearls, and state when each is applied.
5. Run the stepwise management of low glucose: feeding, buccal glucose gel, intravenous dextrose, and when to escalate.
6. Describe the critical sample and glucagon test used for suspected persistent or congenital hypoglycaemia, and the pre-discharge safety checks.
7. Recognise the complications of hypoglycaemia and of being an infant of a diabetic mother, and the prevention that starts before pregnancy.

Neonatal hypoglycaemia (NH) is a low blood glucose concentration in the newborn period. It is the most common neonatal metabolic disturbance and a leading cause of admission of term infants to neonatal units worldwide; its incidence is estimated at 5 to 15% in otherwise healthy neonates, and up to 50% in at-risk groups such as infants of diabetic mothers, preterm infants and infants who are small or large for gestational age.^[1] The infant of a diabetic mother (IDM) is the instructive case: the maternal glucose that crossed the placenta has gone, but the fetal insulin response has not, so glucose falls while insulin continues to drive it down. ^[5]

This page covers both the transitional form, which is a normal-ish adaptation that resolves, and the persistent form, which signals a disorder that must be found. It focuses on full-term infants in the first 72 hours, where the guidance is best developed, and notes where preterm, small-for-gestational-age (SGA) and large-for-gestational-age (LGA) infants differ. All thresholds are quoted as published; because guidelines disagree, the local unit guideline should be followed and any symptomatic infant treated regardless of the number.

A neonate's plasma glucose is normally lower in the first 24 to 48 hours than later in life, because the infant shifts from continuous placental glucose delivery to intermittent feeding. The mean plasma glucose in normal newborns in the first hours after birth is about 55 to 60 mg/dL (about 3 mmol/L), which is close to the adult threshold for neurogenic symptoms but above the threshold for impairment of brain function.^[4] After about 2 days of age the mean is 70 to 100 mg/dL (3.9 to 5.5 mmol/L), as in adults.^[4]

This creates the central difficulty: hypoglycaemia cannot be defined as a single plasma glucose concentration.^[4] It is a state in which glucose supply fails to meet the brain's demand, and the brain is the organ that matters, because the newborn brain has a 2- to 3-fold higher glucose utilisation per kilogram than an adult brain.^[4]

Transitional (adaptive) hypoglycaemia is the fall seen in the first 24 to 72 hours in infants whose counter-regulatory and feeding responses are still maturing, especially those who are preterm, SGA, LGA or infants of mothers with diabetes. It resolves with feeding and warmth and, by definition, clears within about 72 hours. StatPearls defines this as fewer than 3 episodes of moderately low glucose in the 36 to 47 mg/dL range, or resolution within 72 hours after birth.^[1]

Persistent hypoglycaemia is glucose that stays low beyond the transitional period, needs more than feeding to correct, or occurs in an at-risk infant with low measurements on repeated testing. It points to hyperinsulinaemia (the commonest cause), or to endocrine deficiency, inborn error of metabolism, liver disease or perinatal stress. The Pediatric Endocrine Society (PES) recommends that suspected persistent disorders be formally evaluated only once the infant is at least 48 hours of age, because early values overlap with normal transition.^[4]

Classification by context is more useful at the bedside than a single number. The common groups are:

• Impaired metabolic adaptation (transitional): late-preterm, SGA, LGA, IDM, maternal beta-blocker use, cold stress, perinatal asphyxia or sepsis. These infants usually respond to feeding.
• Hyperinsulinaemic: IDM, congenital hyperinsulinism, Beckwith-Wiedemann syndrome, maternal hyperglycaemia or intravenous glucose during labour. These infants cannot turn off insulin, so they need intravenous glucose and, often, further therapy.
• Endocrine deficiency: hypopituitarism, isolated growth hormone or cortisol deficiency, congenital adrenal hyperplasia. Often associated with midline defects or ambiguous genitalia.
• Inborn errors of metabolism and liver disease: galactosaemia, hereditary fructose intolerance, glycogen storage disease, fatty acid oxidation defects, severe liver failure.
• Substrate deficiency: underfeeding, illness, cardiac disease.

This last point shapes investigation: an infant who needs a glucose infusion rate (GIR) above about 8 mg/kg/min to keep glucose normal, or who cannot maintain glucose above 45 mg/dL after 24 hours on 80 to 100 mL/kg/day of 10% dextrose, is likely hyperinsulinaemic rather than simply underfed.^[3][2]

Hypoglycaemia affects up to 15% of all neonates and up to 50% of at-risk populations, including infants of diabetic mothers, preterm infants and infants who are small or large for gestational age.^[1] In otherwise healthy neonates the estimate is 5 to 15%.^[5]

For infants of diabetic mothers, hypoglycaemia develops in 5 to 27% of cases.^[6] Globally, in 2021 an estimated 21.1 million births, about 16.7%, were affected by diabetes in pregnancy.^[6] Congenital malformations are 2 to 3 times more common in newborns of mothers with pregestational diabetes than in the general population, and maternal glycaemic control (HbA1c under 6.5%) in the preconception period and first trimester markedly reduces neonatal complications.^[6]

IDMs also carry the direct metabolic effects of in-utero hyperglycaemia: macrosomia and birth trauma, hypertrophic cardiomyopathy (in about 30% of cases, progressing to heart failure in 5 to 10%), polycythaemia (peripheral venous haematocrit above 65% or haemoglobin above 22 g/dL), respiratory distress, hypocalcaemia (total calcium under 7 mg/dL, 1.8 mmol/L) and hypomagnesaemia (magnesium under 1.5 mg/dL, 0.6 mmol/L).^[6]

Maternal diabetes. Both pregestational (type 1 or type 2) and gestational diabetes place the fetus at risk, with pregestational disease carrying the higher malformation risk. The pathway is described in the pathophysiology section. HbA1c under 6.5% before conception and in the first trimester significantly reduces the complications.^[6]

Other at-risk groups. Prematurity, being small or large for gestational age, maternal beta-blocker therapy in the third trimester, fetal growth restriction (FGR), perinatal asphyxia, hypothermia, sepsis and underfeeding all impair the newborn's ability to maintain glucose.^[2] The British Association of Perinatal Medicine (BAPM) framework applies specifically to full-term infants (born at or after 37+0 weeks) who are at risk, including IDM, maternal beta-blockers and FGR.^[2]

Drugs. Maternal beta-blockers can blunt glycogenolysis and mask hypoglycaemia. Intravenous glucose given to the mother during labour can cause a rebound fetal insulin response. Note that glucose is a treatment and, in excess, part of the problem.

There is no known modifiable fetal risk factor beyond maternal glycaemic control. Female or male sex is not a consistent predictor. Family history matters mainly for congenital hyperinsulinism and endocrine deficiency states.

The whole story of the infant of a diabetic mother can be traced in five steps.

1. Maternal hyperglycaemia crosses the placenta. Glucose moves freely; insulin does not. The fetus is therefore exposed to whatever glucose the mother's blood carries.
2. Fetal hyperinsulinaemia. The fetal pancreatic beta cells respond by secreting excess insulin, which in late gestation also acts as a growth factor, producing macrosomia and organomegaly.
3. Abrupt loss of supply at birth. The cord is clamped and placental glucose stops, but insulin secretion persists with a half-life that keeps glucose falling for hours. Insulin also suppresses glycogenolysis and gluconeogenesis and promotes glucose uptake into tissues.
4. Hypoglycaemia at 1 to 3 hours. In IDMs the blood glucose falls to its lowest between the first and third hour of life, and hypoglycaemia may continue to be a problem for up to 72 hours, and in rare cases up to 7 days.^[6]
5. Counter-regulatory immaturity. The newborn's glucagon and catecholamine responses and hepatic glycogen stores are limited, so recovery is slow; ketogenesis may provide an alternative fuel only after several hours.

The same principles explain why transitional hypoglycaemia is common in all at-risk groups: any infant whose glucose supply falls faster than hepatic glucose production can rise will become hypoglycaemic.

Numbers behind the scenes. Insulin secretion is not suppressed until plasma glucose falls to 55 to 65 mg/dL (3.0 to 3.6 mmol/L) shortly after birth, compared with 80 to 85 mg/dL (4.4 to 4.7 mmol/L) in older infants, children and adults.^[4] The brain uses glucose at roughly 4 to 6 mg/kg/min in early life, two to three times the adult rate per kilogram.^[4] Neuroglycopenic symptoms appear below 50 mg/dL (2.8 mmol/L), and the neurogenic (adrenergic) warning symptoms of older patients appear near 55 mg/dL (3.0 mmol/L).^[4] The target of therapy is therefore not merely to stop a number dropping but to keep fuel above the level at which brain function suffers.

It is worth stating plainly: studies have not established that blood glucose under 47 mg/dL in the newborn causes poor neurodevelopmental outcome; the association may not be causal, and normal infants regularly dip to around 30 mg/dL in the first 1 to 2 hours.^[1] This is why guidelines differ in their thresholds and why prevention of severe, prolonged or symptomatic hypoglycaemia matters more than chasing every low value.

The dangerous feature of neonatal hypoglycaemia is that it can be silent. IDM infants may develop asymptomatic hypoglycaemia as early as 1 hour after birth and usually by 12 hours.^[3] At the other extreme, neuroglycopenic symptoms occur when glucose falls to 50 to 70 mg/dL (2.8 to 3.9 mmol/L).^[4]

Reported symptoms and signs include jitteriness, cyanosis, seizures, apnoeic episodes, tachypnoea, a weak or high-pitched cry, floppiness or lethargy, poor feeding and eye-rolling.^[3] A single value under 2.5 mmol/L in a neonate with abnormal clinical signs is significant regardless of the guideline in use.^[2]

Beyond hypoglycaemia, look for:

• Macrosomia and shoulder dystocia risk, with possible birth injury.
• Hypertrophic cardiomyopathy in about 30% of cases, heart failure in 5 to 10%.^[6]
• Polycythaemia with haematocrit above 65% (or haemoglobin above 22 g/dL), which may produce plethora, respiratory distress and hyperviscosity.^[6]
• Hypocalcaemia (total calcium under 7 mg/dL, 1.8 mmol/L) and hypomagnesaemia (magnesium under 1.5 mg/dL, 0.6 mmol/L).^[6]
• Respiratory distress syndrome from delayed lung maturation and surfactant deficiency.
• Hyperbilirubinaemia and feed intolerance.
• Congenital malformations, 2 to 3 times more common with pregestational diabetes.^[6]

Many well infants have single low values during transition. Repeated confirmation, symptoms and clinical context separate a benign dip from a problem that needs treatment.

When glucose is genuinely low, the question is which of the groups above applies. This is the framework used for a systematic approach:

The key bedside discriminator is the insulin and ketone picture: hyperinsulinaemia suppresses both lipolysis and ketogenesis, so beta-hydroxybutyrate below 1.5 mmol/L and free fatty acids below 1.0 to 1.5 mmol/L at a low glucose suggest hyperinsulinaemia.^[4]

• Use a laboratory plasma glucose for the diagnostic value. Point-of-care meters are useful for screening but their accuracy is limited to about plus or minus 10 to 15 mg/dL (0.6 to 0.8 mmol/L) in the hypoglycaemic range, and test-strip results may differ from actual plasma glucose by 10 to 20 mg/dL.^[4][3]
• Whole blood glucose is about 15% lower than plasma glucose, and delay in processing can drop glucose by up to 6 mg/dL (0.3 mmol/L) per hour through red-cell glycolysis. Record the specimen type and the method when writing the result.^[4]
• If clinical signs are present with a low bedside value, do not wait for the laboratory before treating, but send the laboratory sample with the same draw.

Plasma glucose values are roughly 10 to 18% higher than whole-blood values, so note which was measured.^[3]

At-risk infants should be screened for hypoglycaemia, fed by 1 hour of age and first screened 30 minutes after the feeding.^[3] All at-risk infants, including IDMs, should remain in hospital for at least 24 hours.^[2]

IDM screening schedule (from the infant-of-diabetic-mother review and AAP): assess blood glucose 1 to 2 hours after birth, then every 4 hours until the end of 24 hours. Monitoring may be completed earlier if the infant is willing to suckle, has no abnormalities on examination and has two consecutive normal values.^[6] Target glucose values are at least 40 mg/dL before feeding during the first 48 hours.^{[6] [3]}

General at-risk schedule (BAPM): measure the blood glucose before the second feed, 2 to 4 hours after birth, and if values are stable, before feeds thereafter until normal.^[2] For formula-fed infants give 10 to 15 mL/kg in 3-hourly feeds.^[2]

IDMs may become hypoglycaemic as early as 1 hour and usually by 12 hours, while SGA infants typically fall at around 3 hours and may be at risk for up to 10 days.^[3] The glucose nadir in the healthy newborn is 30 mg/dL at 1 to 2 hours, rising generally above 45 mg/dL by 12 hours.^[3]

When hypoglycaemia persists beyond the transitional window or needs intravenous glucose, the work-up aims to name the cause. PES recommends formal evaluation once the infant is at least 48 hours old, because earlier values overlap with normal transition.^[4]

• Critical sample drawn while glucose is low: glucose, insulin, C-peptide, beta-hydroxybutyrate (ketones), free fatty acids, lactate, ammonia, growth hormone and cortisol. A plasma glucose of 50 mg/dL (2.8 mmol/L) is sufficiently low to elicit the metabolic and neuroendocrine responses required for diagnosis.^[4]
• Glucagon test: 1 mg intravenously, intramuscularly or subcutaneously. An exaggerated glycaemic response (rise above 30 mg/dL, 1.7 mmol/L) is almost pathognomonic of hyperinsulinaemia, and a glucose under 30 mg/dL rise supports deficiency.^[4]
• Imaging and genetics as indicated by endocrine referral; these are outside the scope of this page and are directed by the paediatric endocrinology team.

Because normal neonates run low, several operational frameworks exist. They are not interchangeable and should not be mixed on the same patient. The table uses the publications as quoted.

References: ^[2][3][4][1]. Persistent hypoglycaemia in BAPM terms is more than 2 measurements under 2.0 mmol/L within 72 hours of birth, or severe hypoglycaemia any time, or acute neurological dysfunction with glucose under 2.5 mmol/L, and such infants are referred urgently.^[2]

The IDM-specific threshold summary, as compiled by Suda-Całus et al. from the three guidelines: AAP 2011 uses under 25 mg/dL in the first 4 hours and under 35 mg/dL from 4 to 24 hours on two consecutive measurements, or symptomatic under 40 mg/dL; PES 2015 uses under 50 mg/dL under 48 hours and under 60 mg/dL over 48 hours; BAPM uses a single value under 18 mg/dL or two consecutive measurements under 36 mg/dL. These are guideline targets for treatment decisions in that neonate population.^[6]

A severity staging beyond the numbers is practical:

• Mild/asymptomatic: single low value in the 1.0 to 1.9 mmol/L range (about 18 to 34 mg/dL), feeding responds.
• Significant: repeated lows, or under 1.0 mmol/L at any time, or any value with clinical signs.
• Severe or persistent: failure to correct with feeding, need for intravenous glucose, fitting, apnoea or neurological signs; requires urgent referral and investigation.

The sequence for any at-risk or symptomatic infant:

1. Warm and feed early. Dry, warm and place skin-to-skin where possible; feed within 1 hour of birth.^[3]
2. Screen 30 minutes after the feed and act on the value.^[3]
3. If asymptomatic and glucose is 1.0 to 1.9 mmol/L (18 to 34 mg/dL), give 40% buccal dextrose gel at 200 mg/kg, alongside a feeding plan and recheck.^[2]
4. If glucose is under 1.0 mmol/L at any time, or clinical signs are present, obtain intravenous access, give an intravenous bolus and start an infusion.^[2]
5. If the value is below the guideline threshold but the infant is asymptomatic, refeed and recheck 1 hour later; if it persists at under 25 mg/dL (birth to 4 hours) or under 35 mg/dL (4 to 24 hours), treat intravenously.^[3]

A symptomatic infant with plasma glucose under 40 mg/dL needs intravenous glucose without waiting: the AAP describes a reasonable (although arbitrary) cut-off of 40 mg/dL with a minibolus of 200 mg/kg of glucose (2 mL/kg of dextrose 10% in water) and/or a continuous infusion of dextrose 10% at 80 to 100 mL/kg per day.^[3] BAPM gives a bolus of 2.5 mL/kg of 10% glucose and an infusion starting at 60 mL/kg/day.^[2] Use the GIR and local protocol; these are starting points, not formulas to follow blindly. ^[4][6]

• Dextrose intravenously is the acute drug of treatment, not glucagon first-line. Give 10% dextrose; avoid hypertonic 20% dextrose boluses, because they may cause further hyperinsulinaemia and rebound hypoglycaemia.^[6]
• Glucagon is the adjunct for persistent hypoglycaemia or when ketogenesis is impaired. Doses of 0.5 to 1.0 mg (independent of weight), given intravenously, intramuscularly or subcutaneously, are usually effective; 1 mg is the standard test/therapeutic dose, with lower doses of 0.03 mg/kg carrying less risk of transient nausea and vomiting but possibly being ineffective unless given intravenously.^[4]
• Glucocorticoids should not be given non-specifically for neonatal hypoglycaemia: PES discourages their routine use and prefers targeted therapy and nutritional support.^[5]
• Birth dose and infusion rates should be adjusted to reach the target (at least 2.0 mmol/L, or at least 3.0 mmol/L if hyperinsulinaemia is suspected under 48 hours) and to avoid large swings. The GIR in mg/kg/min is estimated by (infusion rate in mL/kg/day divided by 144) multiplied by the glucose concentration in percent.^[2]
• Dextrose 10% at 4 to 8 mg/kg/min is the review figure for IDMs; escalation is needed when more glucose is required.^[6]

• Urgent paediatric review, intravenous glucose, and investigation of the cause.
• Consider hyperinsulinaemia if glucose stays under 2.0 mmol/L on at least 3 occasions in the first 48 hours or a glucose dose above 8 mg/kg/min is needed.^[2]
• A safety fast of 6 to 8 hours before discharge should be considered in at-risk infants without a suspected persistent disorder, to confirm that a plasma glucose above 60 mg/dL can be maintained.^[4]
• Discharge only after maintenance of blood glucose above 2.0 mmol/L on at least 2 consecutive occasions and effective feeding.^[2] In the AAP framework, the infant must maintain normal plasma glucose through at least 3 feed-fast periods before discharge where postnatal glucose homeostasis has been documented to be inadequate.^{[3] [4]}

Feeding is the treatment. Breastfeeding or formula within 1 hour, correct latch and volume, and warming are first-line. For a feed given before screening, the value should still be taken. For formula-fed infants 10 to 15 mL/kg 3-hourly volumes are used.^[2] Skin-to-skin contact and avoidance of cold stress support adaptation.

Congenital hyperinsulinaemia or a focal lesion (for example nesidioblastosis or focal adenomatous disease) may need specialist medical therapy or, rarely, surgery. This page does not detail those protocols; they are the province of paediatric endocrinology and should be managed in a tertiary centre. PES specifically recommends glucagon, surgical intervention and nutritional therapies rather than non-specific glucocorticoids for persistent disease.^[5]

• Re-screening and glucose monitoring for the full first 24 hours in IDMs; SGA infants may need monitoring for longer, up to 10 days in high-risk cases.^[3]
• Infants who needed intravenous glucose, or who failed the safety fast, should have planned follow-up with community midwifery and paediatric review.
• Any infant with a confirmed persistent disorder needs specialist endocrine follow-up and family screening where relevant.

Refer urgently (same day, neonatal unit) any neonate with persistent hypoglycaemia (more than 2 measurements under 2.0 mmol/L within 72 hours), severe hypoglycaemia under 1.0 mmol/L any time, or signs of acute neurological dysfunction with glucose under 2.5 mmol/L.^[2] Also refer any at-risk infant who cannot maintain glucose on standard feeding and any suspected IDM with cardiomyopathy, severe polycythaemia or birth injury.

• Neurological. The main feared consequence is brain injury, but the causal link between moderately low glucose (36 to 47 mg/dL) and poor neurodevelopmental outcome has not been proven; the association may not be causal.^[1] This uncertainty argues for preventing severe, prolonged or symptomatic hypoglycaemia rather than chasing transient dips. Symptomatic episodes and glucose under 1.0 mmol/L remain indications for urgent treatment on every framework.
• Seizures and apnoea, which are neuroglycopenic events.
• Rebound and over-treatment causing hyperglycaemia and osmotic shifts if hypertonic boluses are used.^[6]

• Hypertrophic cardiomyopathy (30%, heart failure in 5 to 10%), polycythaemia (haematocrit above 65%), hypocalcaemia and hypomagnesaemia, respiratory distress syndrome, macrosomia with birth (especially shoulder) injury, congenital malformations 2 to 3 times more frequent with pregestational diabetes, and hyperbilirubinaemia.^[6]

Transitional hypoglycaemia resolves within 24 to 72 hours and, in IDMs, glucose is usually stable by 48 to 72 hours, though rarely it persists to 7 days.^[6] Persistent hypoglycaemia that remains beyond 48 hours demands diagnosis and, once its cause is treated, outcomes depend on that cause. Congenital hyperinsulinaemia has a high recurrence risk but good outcomes with appropriate therapy; endocrine and metabolic causes depend on the underlying condition.

Neurodevelopmental prognosis is best protected by avoiding severe, symptomatic or prolonged hypoglycaemia and by treating IDMs comprehensively, including their cardiopulmonary complications.

Prevention starts before pregnancy:

• Glycaemic control: an HbA1c under 6.5% before conception and in the first trimester markedly reduces IDM complications, including malformations and hypoglycaemia.^[6]
• Antenatal care: screening for and treatment of gestational diabetes, and avoidance of maternal hyperglycaemia in labour; avoiding unnecessary intravenous glucose during labour reduces fetal insulin drive.
• Intrapartum: plan delivery timing and mode for suspected macrosomia; anticipate the need for early glucose screening.
• Postnatal: early and regular feeding, warmth, skin-to-skin contact, and a written screening schedule for every at-risk infant. All at-risk infants, including IDMs, remain in hospital at least 24 hours.^[2]
• Feeding support: mothers need help establishing breastfeeding or formula feeding; IDMs often have poor suck because of hypoglycaemia or prematurity.
• For suspected congenital disorders: PES recommends 6 to 8 hour safety fast and a plasma glucose above 60 mg/dL before discharge in selected at-risk neonates.^[4]

Prematurity and SGA. Preterm and SGA infants are at risk from 3 hours of age and may remain at risk for up to 10 days, requiring monitoring beyond the IDM 24-hour window.^[3] Late-preterm and SGA infants need glucose monitoring for at least 24 hours.^[3]

LGA. Large infants without IDM (for example after maternal obesity or post-dates pregnancy) are also at risk and need the same screening.

Multiple pregnancy. Shared placental circulation and growth discordance raise risk; screen as for other at-risk infants.

Maternal beta-blockers. Treat these infants on the IDM timeline rather than assuming they are low risk.

Infants with macrosomia but normoglycaemic mothers. Still at risk; use the at-risk pathway.

Older children. Once a child is able to communicate symptoms, the hypoglycaemia work-up follows different criteria (for example Whipple triad; a threshold under 60 mg/dL for infants who cannot reliably communicate symptoms).^[4] This page does not cover childhood hypoglycaemia in detail.

• Warmth and feeding are the treatments most places can give: keep the infant warm, feed within 1 hour, and recheck.
• Where a laboratory is available, use laboratory plasma glucose for diagnostic decisions; bedside meters vary by 10 to 20 mg/dL.^[3]
• Where 40% dextrose gel is unavailable, frequent feeding and, when glucose is under 1.0 mmol/L, intravenous dextrose 10% at the starting rates above are the mainstays. Hypertonic 20% boluses should still be avoided.^[6]
• If intravenous access is not immediately possible, give buccal gel if available and feed, and arrange transfer.
• BAPM volumes of 10 to 15 mL/kg formula every 3 hours can be used to standardise feeds where breastmilk is not yet established.^[2]
• All at-risk infants, including IDMs, should stay in hospital at least 24 hours even where resources are stretched, because that is when IDM hypoglycaemia most often occurs.^[2][6]

• Neonatal sepsis and perinatal stress (differential for low glucose and poor feeding).
• Infant feeding and colic (establishing early feeds and avoiding hypoglycaemia).
• Congenital hypothyroidism and newborn screening (endocrine causes of prolonged hypoglycaemia).
• Neonatal seizures and hypoxic-ischaemic encephalopathy (neurological consequences of severe hypoglycaemia).
• Type 1 diabetes mellitus and diabetic ketoacidosis in pregnancy-related context (maternal diabetes and its management).
• Fluids, electrolytes and acid-base (intravenous dextrose and glucose requirements).