Mothers' illness

Can I breastfeed if I am sick?

Breastfeeding by mothers who are sick rarely poses a risk to their babies, and any medication they take is unlikely to cause harm. However, severe illness can affect the milk supply. Mothers with viral infections such as the flu virus and COVID-19, should continue to breastfeed. By the time they feel ill, the baby has already been exposed to the virus, so stopping breastfeeding won’t help, and it may prevent the baby from receiving useful antibodies and the best nutrition. Similarly, mothers with bacterial infections generally do not pose a risk to babies. Those with tuberculosis or brucellosis may have to stop breastfeeding temporarily and depending on the situation, those with the AIDS and HTLV virus may need to wean. Mothers with chronic disease often benefit from additional breastfeeding support.  

A) Describing breastfeeding during illness

Severe infections and illness can:

A mother who breastfeeds while sick rarely poses a risk to the baby, and any medication she takes is unlikely to harm the baby. However, mothers with chronic disease tend to stop breastfeeding earlier than healthy mothers (Scime 2020).

A mother who must stay in hospital should try to have her baby stay with her or have the baby regularly brought to her. When this is not possible, she should express regularly. Infrequent or ineffective expressing can decrease milk supply.

A few illnesses can reduce the amount of vitamins and minerals in the mother’s body and in her breast milk and her baby’s growth and health should be monitored.

Please discuss any concerns with your health-care providers. Breastfeeding specialists are often helpful in this situation.

B) Viral infections

1) Common viruses

In general, mothers with a viral infection causing a cold, the flu, or the stomach flu should continue to breastfeed.

Viruses enter a body, reproduce, and are then shed and infect others. All of this can happen before the person feels sick. This means that babies of infected mothers are exposed to viruses before the mother knows she is sick. Stopping breastfeeding when she begins to feel ill will not protect the baby from infection.

In addition, as soon as a virus enters a mother’s body, the breast milk immediately acquires antibodies and infection-fighting agents that work to protect the baby. Stopping breastfeeding removes this protection.

A mother who has the stomach flu should try to stay hydrated. If she is too sick or dehydrated to breastfeed, her baby may need milk supplements for a few hours. Breastfeeding should resume as soon as the mother feels able.

2) COVID-19 (corona) virus 

This is a new virus and knowledge about its behavior is evolving quickly. Resources for more information include:

  • The World Health Organization  
  • The Center for Disease Control  
  • The Academy of Breastfeeding Medicine

All recognized medical organizations recommended that eligible individuals are vaccinated against COVID-19. This includes pregnant and breastfeeding women as vaccination protects both mother and child from infection.  Furthermore, pregnant women are at a higher risk of severe disease if they develop a COVID-19 infection.

a) Reasons for continuing to breastfeed if the mother is infected with COVID-19

Newborns and infants are at low risk of significant illness from COVID-19 infection. Among the cases of confirmed COVID-19 infection in young children, most have experienced only mild or asymptomatic illness (Kyle 2020). Adults, and in particular older adults are more likely to have severe illness.  

While parts of the COVID-19 virus (RNA) have been found in breast milk (Chambers 2020; Gross 2020), breastfeeding by mothers who are infected with COVID-19 does not appear to increase the risk of it in babies (Krogstad 2021; Lubbe 2020). Rather it may protect them (Bartick 2021; Pace 2021).

Antibodies to COVID-19 have been found in breast milk and may reduce the risk of the baby being infected. COVID-19 infections can result in an over-reaction of the immune system and further illness. Breast milk may modulate the baby's response as it contains both pro- and anti-inflammatory agents (Green 2020). Indeed, breastfeeding during the COVID-19 pandemic is has benefits for the whole family.  

b) How to breastfeed if the mother is infected with COVID-19

Mothers with COVID-19 infection should prevent infection of their baby by (Amatya 2020; WHO 2020):

  • Washing their hands before touching the baby.
  • Wearing a face mask when near the baby.
  • Replacing damp masks and discarding used ones.
  • Cleaning their breasts and chest with soap and water before feeding if they have coughed or sneezed on the exposed breasts and chest.

Mothers who are pumping should wash their hands before touching any pump parts and clean their pump parts after each use. 

Breastfeeding mothers should be offered vaccination if they are eligible and no contraindications exist. Breastfeeding is not a reason to avoid the COVID-19 vaccine. Rather, it may protect not only the mother but also the baby as antibodies generated by the vaccine appear in breast milk (Perl 2021).

3) Viruses that suppress the immune system

Mothers infected with the human T cell leukemia virus 1 or 2 (HTLV1 or 2) and some mothers with HIV infection, the virus which causes AIDS, may be at risk of transmitting the virus through breast milk and infecting the baby. 

4) Zika virus

The Zika virus has been found in breast milk, but breastfeeding by mothers infected with the virus has not been shown to result in infection in the baby (Centeno-Tablante 2021). The World Health Organization and Centers for Disease Control and Prevention recommend that mothers with the virus continue to breastfeed as the benefits outweigh the risks (WHO 2016; CDC 2017).

5) Hepatitis virus

Breastfeeding is compatible (poses little or no risk to the baby) when mothers are infected with hepatitis A, B, and C.

Mothers with hepatitis A should continue to breastfeed. Hepatitis A infection in the baby can be prevented with an antibody injection (hepatitis A immune globulin). A vaccine can also be used if the baby is older than six months of age. 

Babies whose mothers have hepatitis B are mostly protected from infection by immunization at birth (hepatitis B immune globulin and hepatitis B vaccine). Subsequent hepatitis vaccine is given around one month and at six months of age (CDC 2015; Schillie 2018). There is a slight increase in the risk of the baby being infected with hepatitis B if the mother has a high blood level of hepatitis B during pregnancy (Zhou 2021). 

Hepatitis C does not appear to be transmitted to babies by breastfeeding (Yeung 2014).

A few authorities recommend that a mother who has bleeding nipple damage and a hepatitis B or C infection should avoid breastfeeding and express and throw out her milk until her nipples have stopped bleeding but there is not enough research to make a firm recommendation. 

6) Cytomegalovirus

Cytomegalovirus (CMV) is a common infection in mothers. Blood tests are available to diagnose the infection. Babies whose mothers develop CMV infection before giving birth can have nervous system problems and deafness.

The virus can be passed to the baby through breast milk (Antona 2010). Infection in healthy, full-term babies is generally minor and creates no long-term problems. Very small premature babies whose immune systems are weak are at a higher risk of CMV infection but at the current time, evidence is insufficient to support withholding the mother’s own milk (Parker 2021).


7) Herpes zoster (chicken pox and shingles) and herpes simplex

Mothers may be ill with chicken pox or shingles, a blistering rash of one side of the chest or face. These are both cause by the same virus (herpes zoster).

Infections of the nipple with the herpes simplex virus can be painful.

Both viruses can pose a risk to the baby.

C) Bacterial infections

Bacterial infections are usually treated with antibiotics, which are mostly compatible with breastfeeding. Bacterial infections generally do not pose a risk to babies unless the baby is directly exposed to pus or infected tissue.

Bacteria in breast milk rarely causes infection in the baby (Boué 2018). Special breastfeeding precautions may be needed if the mother is infected with brucellosis, tuberculosis of the lungs or breast, or botulism.

D) Diabetes

1) Describing diabetes

Diabetes is a disease that results in excess sugar in the blood. 

Diabetes may be:

  • Type 1 caused by the body attacking insulin-producing cells
  • Type 2 caused by resistance to insulin
  • Gestational diabetes, which develops during pregnancy

Breastfeeding prevents diabetes and has benefits for mothers who have developed it. A diabetic mother’s milk maybe slightly different but there is no evidence of this causing problems. Breastfeeding also reduces the risk of diabetes in children.

2) Breastfeeding with diabetes

All breastfeeding diabetic mothers should discuss managing their disease with their health-care providers. The extra calories needed to make milk may affect how much diabetic medication or insulin is needed (Steube 2016).

Mothers with diabetes may consider manually expressing colostrum (prenatal expression) before the baby’s birth. This may limit the need for infant formula supplements. Please discuss this with your health-care providers as it may stimulate early labour.

Mothers who have diabetes are encouraged to breastfeed and need close monitoring of their sugar levels after delivery (Achong 2012; Achong 2018; Ringholm 2020).

The babies of diabetic mothers need to be carefully watched as diabetes can delay the milk coming in or cause a low milk supply. They are also more likely to have low blood sugar levels. Keeping the baby skin-to-skin and allowing the baby to breastfeed early and often can help keep the baby’s sugar levels normal. Treatment of low sugar levels may include giving the baby special sugar (dextrose gel) or even intravenous sugar (glucose).

Insulin and some drugs commonly used to treat diabetes, such as metformin and glyburide, are compatible with breastfeeding. There is less information about the safety of newer medications (Anderson 2018).

Some breastfeeding mothers have been told to eat carbohydrates at night to prevent their sugar levels from going too low. This may not be necessary (Ringholm 2019).

E) Illness related to breastfeeding

1) Lactation ketoacidosis

Ketoacidosis develops when the body cannot get sugar (glucose) from its stores (glycogen) and instead breaks down fat and protein to feed itself (Seaton 2019). This produces ketones, which make the blood acidic. When ketoacidosis develops during breastfeeding, it is called lactation ketoacidosis. This condition is very uncommon but can have serious consequences.

Patients suffering from this may experience a variety of symptoms. From most to least common, mothers may (Al Alawi 2020):

  • Have nausea or vomiting.
  • Feel unwell.
  • Have tummy pain.
  • Experience shortness of breath.
  • Have a headache.
  • Feel their heartbeat.

Documented triggers and causes include (Al Alawi 2019; Gleeson 2016; Nnodum 2019):

  • Fasting
  • Not eating carbohydrates (ketogenic diet)
  • Breastfeeding
  • Vomiting and diarrhea
  • Bladder infections or other illness when combined with a low carbohydrate diet

Treatment includes giving sugar, salts (electrolytes), agents to reduce the acidity of the blood (sodium bicarbonate), and fluids into a vein (IV), and insulin.

2) Lactation anaphylaxis

While extremely rare, it is possible for breastfeeding mothers to have severe and dangerous allergic reactions (anaphylaxis) caused by breastfeeding. Such mothers have episodes of hives, wheezing, shortness of breath, vomiting, and low blood pressure soon after delivery (Pescatore et al. 2019).

F) Chronic illness

Each illness has its own challenges for breastfeeding which may include:

Some genetic conditions can affect breastfeeding.

Mothers already fatigued by chronic disease can struggle with the demands of caring for a baby. Breastfeeding is often seen as adding to these demands and mothers may be discouraged from breastfeeding. This attitude is not balanced by the benefits of breastfeeding for mothers, their babies, and the family as a whole.  

For example, there is no evidence that breastfeeding is harmful to mothers with multiple sclerosis. Indeed, there are studies that show such mothers have fewer relapses than those who infant formula-feed or partially breastfeed. This may be due to breastfeeding delaying the return of their menses.

Mothers with chronic conditions may benefit from extra help in caring for their babies. Support from peers and a breastfeeding specialist may be very helpful. Please discuss your situation with your health-care providers.

G) Mental health challenges

Sadness, depression, anxiety, and other mental health challenges are common in mothers after delivery. Treatment options include support, counselling, and medication. 


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