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Increased risk of low blood sugars after birth: information for parents

Patient information A-Z

You have been given this leaflet because your baby is at increased risk of having low blood glucose (also called low blood sugar or hypoglycaemia) after birth.

We hope it answers some of the questions you may have, but please speak to a midwife if you have further questions.

What is low blood glucose?

Babies who are small, premature, unwell at birth, or whose mothers have diabetes or have taken certain medication (e.g. beta-blockers), may have low blood glucose in the first few hours and days after birth.

If your baby is in one of these at risk groups, it is recommended that they have some blood tests to check their blood glucose level. Extremely low blood glucose, if not treated, can cause brain injury resulting in developmental problems. If low blood glucose is identified quickly, it can be treated to avoid harm to your baby. It is especially important that babies at risk of low blood glucose levels are fed often and are kept warm as cold babies use their glucose more quickly.

How do we test your baby’s blood glucose levels?

Your baby’s blood glucose is tested by a heel-prick blood test. A very small amount of blood is needed and it can be done while you are holding your baby, including while in skin-to-skin contact. The first blood test should be done before the second feed (two to four hours after birth), and repeated until the three blood glucose levels have all been stable. You and your baby will need to stay in hospital for the blood tests. You will know the result of the test straight away.

What happens if my baby’s blood glucose is low?

If you are breastfeeding or chestfeeding and your baby’s blood glucose is low (less than 2.6mmol/L) we recommend giving dextrose (sugar) gel. This is gently rubbed into the inside of your baby’s cheek (called a buccal dose). You will then be asked to breastfeed / chestfeed your baby, If your baby does not actively feed at the breast / chest, then it is important to give some expressed colostrum (early breastmilk). You might therefore find it helpful to hand express colostrum during pregnancy and to have brought this into the hospital with you. Further information about hand expressing is below.

Your baby will need another blood test after the gel and a feed to check the glucose level has returned to normal. If glucose levels remain low and there is no available expressed breast milk, you will be advised to give infant formula until blood sugars have stabilised again.

If at any point the glucose level is very low (1.5mmol/L or less), or if the level does not return to normal after the above measures, the neonatal team may also advise that urgent treatment for your baby is required on the Neonatal Unit. Staff will explain any treatment that might be needed. In most cases, low blood glucose quickly improves within 24-48 hours and your baby will have no further problems.

What will help to minimise the risk of low blood glucose?

Skin-to-skin contact

  • No matter how you choose to feed your baby, skin-to-skin contact is beneficial. Place your naked baby on your bare chest as this skin-to-skin contact helps keep your baby calm and warm which means they use up less energy. It also helps to establish breastfeeding / chestfeeding. During skin-to-skin contact your baby should wear a hat and a nappy and be kept warm with a blanket or towel around their back.

Keep your baby warm

  • Put a hat on your baby for the first 24 hours after their birth. Keep your baby in skin contact on your chest covered with a blanket. If they are not skin-to-skin they need to be dressed and kept warm with blankets. Babies who are cold use up a lot of energy trying to keep warm and therefore use extra glucose.

Feed as soon as possible after birth

  • Ask a member of staff to support you with feeding until you are confident, and make sure you know how to tell if breastfeeding / chestfeeding is going well. If you are bottle feeding, ask a member of staff how much formula to give your baby.

Feed regularly in the first few days

  • Whenever you notice feeding cues, which include rapid eye movements under the eyelids, mouth and tongue movements, body movements and sounds, or sucking on a fist, offer your baby a feed. Don’t wait for your baby to cry – this can be a late sign of hunger.

Feed for as long, or as much, as your baby wants.

  • This ensures your baby gets as much breast/ chest milk as possible.

Feed as often as baby wants

Do not leave your baby more than three hours between feeds in the few days after birth and until the glucose levels are stable. If your baby is not showing any feeding cues yet, hold them skin-to-skin and start to offer a feed about three hours after the start of the previous feed.

Express your milk (colostrum).

  • If you are breast feeding/ chest feeding and your baby struggles to feed, try to give some expressed milk. A member of staff will show you how to hand express your milk and give you “The Golden Rules of Expressing” pack or you can watch the UNICEF hand expression video on the UNICEF Website (opens in a new tab)
  • If possible, it is good to have a small amount of expressed milk saved in case you need it later, so try to express a little extra breast milk in between feeds. Ask your midwife how to store your expressed milk.

If you have been given this leaflet before your baby is born, it is helpful if you can begin to express some colostrum ready for your baby should they need it. This can begin from 36 weeks of pregnancy. Speak to your midwife about an information and collection pack.

Important safety information

  • Infant feeding syringes have a free-fastening lid which must be removed and disposed of before giving expressed colostrum or milk to your baby. This should ideally happen as soon as the syringe is removed from the fridge. If giving recently expressed colostrum, discard the cap before expressing.
  • Always keep syringes and lids away from babies and children.

How can I check that my baby is well?

Don’t hesitate to tell staff if you are worried about your baby. If your baby appears to be unwell, this could be a sign that they have low blood glucose. As well as doing blood tests, staff will observe your baby to check they are well, but your observations are also important, as you are with your baby all the time so know your baby best. It is important that you tell staff if you are worried that there is something wrong with your baby, as parents’ instincts are often correct.

The following are signs that your baby is well:

Is your baby feeding well?

  • In the first few days your baby should feed effectively at least every three hours, until blood glucose is stable, and then at least eight times in 24 hours. Ask a member of staff how to tell if your baby is attached and feeding effectively at the breast, or how much formula they need. If your baby becomes less interested in feeding than before, this may be a sign they are unwell and you should raise this with a member of staff.
  • If you are bottle feeding, make sure you are not over-feeding your baby. Offer the bottle when he/ she shows feeding cues and observe for signs that he/ she wants a break. Don’t necessarily expect your baby to finish a bottle – let them take as much milk as they want. Small, regular feeds often works better in the 1st few days to keep the glucose levels stable.

Is your baby warm enough?

  • Your baby should feel slightly warm to touch, although hands and feet can often feel a little cooler. Place your hands on their chest to check this. Whilst your baby is having their blood sugars tested the staff will use a thermometer to check their temperature is between 36.50C and 37.50C.

Is your baby alert and responding to you?

  • When your baby is awake, they will look at you and pay attention to your voice and gestures. If you try to wake your baby, they should respond to you in some way.

Is your baby’s muscle tone normal?

  • A sleeping baby is very relaxed, but should still have some muscle tone in their body, arms and legs and should respond to your touch. If your baby feels completely floppy, with no muscle tone when you lift their arms or legs, or if your baby is making repeated strong, jerky movements, this is a sign they may be unwell. It can be normal to make brief, light, jerky movements. Ask a member of the team if you are not sure about your baby’s movements.

What happens when I go home with my baby?

It is recommended that your baby stays in hospital for 24 hours after birth. After that, if your baby’s blood glucose is stable and they are feeding well, you will be able to go home. Once you are home, no special care is needed. As with all newborn babies, you should continue to look for signs that your baby is well, and seek medical advice if you are worried at all about your baby.

Before you go home, make sure you know how to tell if your baby is feeding well. A member of staff will explain the normal pattern of changes in the colour of dirty nappies and number of wet/ dirty nappies. If you are breastfeeding/ chest feeding there are daily information sessions on Lady Mary ward - please ensure you attend a session before you go home. It is important to make sure that your baby feeds well, at least 8 times every 24 hours. Most newborn babies feed more often than this once they are over 24 hours of age.

You can now start to feed your baby responsively. Ward staff will explain what this means. There is no need to continue waking your baby to feed every two to three hours as long as they have had at least 8 feeds over 24 hours, unless this has been recommended for a particular reason.

References/ Sources of evidence

BAPM (2017) Identification and Management of neonatal hypoglycaemia in the full term infant: a framework for practice. British Association of Perinatal Medicine

Is your baby’s colour normal?

Look at the colour of the lips and tongue – they should be pink.

Is your baby breathing easily?

Babies’ breathing can be quite irregular, sometimes pausing for a few seconds and then being very fast for a few seconds. If you notice your baby is breathing very fast for a continuous period (more than 60 breaths per minute), or seems to be struggling to breathe, with very deep chest movements, nostrils flaring or making noises with each breath out – this is not normal.

For further advice on signs & symptoms of an unwell baby and who to contact, please refer to our postnatal information on the CUH Website.

References/ Sources of evidence

BAPM (2017) Identification and Management of neonatal hypoglycaemia in the full term infant: a framework for practice. British Association of Perinatal Medicine

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