SARS-CoV-2 and Mother-Baby Separation

DENA DURAN, LLL LEADER, NEW YORK CITY AND IDAHO, USA

Risks of Separation (Part 1)

Skip to:Case Review of Infants Born to COVID-19 Positive Mothers (Part 2)

The World Health Organisation (WHO), UNICEF, the United Nations (UN), La Leche League International (LLLI), and the Academy of Breastfeeding Medicine (ABM) all recommend continuing to breastfeed during COVID-19 illness if possible, while following hygiene precautions (WHO, 2019; UNICEF, n.d.; UNFPA, 2020; LLLI, 2020; ABM, 2020).

Despite this, certain hospitals across the world are sometimes creating protocols that call for mother-baby separation at birth when the mother is presumed or positive for SARS-CoV-2 infection or a “person under investigation” (PUI) for SARS-CoV-2 infection. There are stories like these from China, France, Italy, Spain, and the United States (USA). Country policies vary greatly with Great Britain’s Royal College of Obstetricians and Gynecologists opposing separation, China setting a policy for separation, and the Centers for Disease Control and Prevention (CDC) in the USA recommending separation on a case-by case basis (RCOG, 2020; Wang et al. 2020; CDC, 2020).

So far, I have seen no clear, compelling data that contraindicates keeping mother and baby together but much that supports it.

SARS-CoV-2, which causes the illness known as COVID-19, is a lipid-enveloped virus: it has a “shell” of fat around a strand of RNA (a type of genetic material). Prior research by Pfaender et al (2013) has shown HCV (Hepatitis C), H1N1 (Swine flu) and some other lipid-enveloped RNA-stranded viruses are destroyed in vitro by human milk via slicing of the lipid envelope by free fatty acids generated from triglycerides (a type of fat) by lipases (fat digesting enzymes) in the milk (Pfaender et al., 2013).

The research concludes that “nursing by HCV-positive mothers is unlikely to play a major role in vertical transmission [transmission from mother to baby]” (Pfaender et al., 2013). To my knowledge it has not been scientifically proven that a mother with a lipid-enveloped virus, like SARS-CoV-2, will transmit the active, infective virus to the nursling via her milk. Instead, research suggests that breast milk inactivates the virus, reduces infectivity, and is effective in helping the infant fight the virus (Pfaender et al., 2013). Indeed the first 26 samples of mothers’ milk tested for SARS-CoV-2 were negative (Chen et al., 2020; Egloff et al., 2020). One report has found the virus in human milk (Groß et al., 2020) but its presence in milk does not mean that the virus is infectious to the infant and must be considered alongside the critical immune factors and antibodies also present in human milk.  Recent research shows that many women positive for COVID-19 illness passed along antibodies to the virus in their milk (Fox et al, 2020).

The CDC specifically states in their advice that “Although it is well recognized that the ideal setting for care of a healthy term newborn while in the hospital is within the mother’s room, temporary separation of the newborn from a mother with confirmed or suspected COVID-19 should be strongly considered to reduce the risk of transmission to the neonate …  recommendations will be updated as new information informing the risk-benefit of maternal-infant separation is available (CDC, 2020a).”

Though we don’t have a full picture of SARS-CoV-2, we do know a lot about the necessity of mother-infant closeness. My hope is that the information in this article will help Leaders and the parents they help to have scientifically-backed information all in one place; to help parents and their health care providers make an informed decision that takes into account the known risks of separation.

The risks and benefits of separation should be weighed very carefully and take into account the severity of the mother’s illness, the ability to take precautions (wearing a mask, careful hand washing) and still care for and breastfeed her baby, and the effect separation has on the physiological systems of both mother and baby. The risks of separation are very great.

Risks of separation of mother and baby immediately postpartum

1. Dysregulation of the physiological systems of mother and baby

• A mother’s body helps to regulate a baby’s temperature, breathing, heart rate, energy use, acid-base balance, and overall homeostasis (maintenance of body systems) (Winberg, 2005). Removing the baby from the mother introduces the risk of dysregulation of these vital processes.

2. Introduction of loneliness and an allostatic load (the cumulative negative effects of chronic stress on the body)

• Several studies have shown that loneliness (i.e., separation) can induce grave consequences in humans. These range from a dull sense of something wrong in light cases to overall negative systemic effects in extreme cases. Removing a newborn from his/her mother is an extreme case (Lupien et al., 2009) (Footnote A) and should be very carefully considered. The following excerpt tells us that the following systems are affected by stress: “the sympathetic-adrenal-medullary (SAM) system, the hypothalamic-pituitary-adrenal (HPA) axis, as well as cardiovascular, metabolic, neural, endocrine and immune systems …and continued stress can cause dysregulation of many of these systems.” (Okamura et al., 2009)
• The key worry here is the stress hormone cortisol. Sapolsky (1996), in his classic paper in Science, demonstrated that cortisol specifically damaged a part of the brain called the hippocampus, a structure critical in learning and memory. As a number of recent studies on sleep training have found, separation increases cortisol (Buss et al., 2012; Middlemiss et al., 2011; Navarez, 2013).
• The separation stresses the mother as well, as is discussed in Stuebe’s recent statement published in Breastfeeding Medicine on the same subject (Stuebe, 2020).  Stuebe notes that the “associated physiologic stress could worsen the mother’s disease course.” (Stuebe, 2020)

3. Altered brain development

Brain development can be negatively affected by stress; changing behavioural and physiological responses (McEwen, 2006; Harvard University, 2014). Some of the possible effects of an altered HPA axis or SAM system include:

• Stress-related disorders that can affect mental health (e.g., depression, anxiety disorders, alcoholism, drug abuse) and physical health (e.g., cardiovascular disease, diabetes, stroke) (Harvard University, 2014).
• Chronic stress can lead to suppression of immune function, contribute to metabolic syndrome, bone mineral loss, and muscle atrophy (Harvard University, 2014).
• Long-term increases in cortisol levels can alter the function of a number of neural systems, and even change the structure of parts of the brain essential for learning and memory (Harvard University, 2014). See also Sapolsky (1996).

4. Reduction in cellular immunity

• Effectivity of natural killer (NK) cells (a type of lymphocyte that is crucial to the immune system) is reduced in persons under stress (Kiecolt-Glaser et al., 1984). NK cells are important in fighting viral infection (Brandtstadter & Yang, 2019).) Though we don’t know much about the specific mechanisms of SARS-CoV-2 or how our body fights it (i.e., how involved NK cells are), it seems a large risk to knowingly reduce a known member of the fighting team. This is a risk for both the mother and the baby, as separation puts both of them in stress mode.
• Reduced effectiveness of T-lymphocytes (specialized white blood cells) has also been shown in persons under stress (Kiecolt-Glaser et al., 1984). Again, to reduce the effectiveness of the immune system of mother and baby through the stress of separation carries a risk.

5. Increased Inflammation

Another system that is activated during prolonged stress is the inflammatory response system (Kendall-Tackett, 2013). Not only does increased inflammation have serious implications for long-term health (Kendall-Tackett, 2010), but it is specifically a problem in the case of COVID-19 in children. According to the Centers for Disease Control and Prevention, COVID-19 activates a multi-system inflammatory response (CDC, 2020). When COVID-19 seriously affects, or even kills children, it is because of inflammation.

• Research on early life adversity is instructive here. Separation, inconsistent care, and abuse are all childhood stressors that have a lifetime impact on the inflammatory response (e.g., Gouin et al., 2020; Oshir et al., 2020). Slopen et al. (2015) found that prenatal and early childhood exposure to adversity increased systemic inflammation in the adult offspring by three times.
• Because of these previous findings, it can be reasonably argued that separation activates the inflammatory response system in both mother and baby, which arguably makes babies more vulnerable to the serious harms caused by COVID-19. Rather than protecting them, separation puts them directly in harm’s way.

6. Increased difficulty bonding for mother and baby

• Skin-to-skin contact increases oxytocin which, among other physiological effects, enhances bonding for mother and baby (Handlin, et al., 2009). To deny the pair this important positive hormonal boost at this crucial time can affect bonding and social relationships long past the current pandemic (Crenshaw, 2014). The stress system specifically suppresses oxytocin (Handlin et al., 2009) Conversely, both breastfeeding and skin to skin increases oxytocin which suppresses the stress system, making babies less vulnerable to possible infection (Handlin et al., 2009; Heinrich et al., 2001).
• Babies cry less and interact with their mothers more when they are put skin-to-skin early (WHO, 2019). To remove this means the baby may cry more, mother and baby may interact less and they may bond to each other less, resulting in negative maternal behavior (Crenshaw, 2014). (Footnote B)

7. Increased risk of breastfeeding “failing” or being more difficult.
   The risk of undermining the breastfeeding relationship through early separation should not be discounted.

• Separation of mother and baby has been shown to reduce milk production and the likelihood of exclusive breastfeeding (WHO, 2019; Bystrova et al., 2007; Elander & Lindberg, 1984). In one study, an average of 3.3 days separation (range 1-6 days) in the first week of life resulted in 37% exclusively breastfed infants at three months of age versus 72% in the non-separated group (Elander & Lindberg, 1984).
• The benefits of the normal nutrition of human milk are huge. Human milk contains many immune factors and unique nutritional components that can help a baby fight off infection—factors that are given to baby with every single breastfeed. (Footnote C) Because the risk of infection from SARS-CoV-2 is so high (both immediately postpartum from hospital sources, perhaps from mother, and after discharge in the home/everyday life environment), the risks of removing these immune factors should be very carefully considered.
• If breastfeeding fails as a result of the separation, a formula-fed child has increased risk of several diseases, including upper and lower respiratory ailments, colds, viruses and bacterial infections, intestinal disorders, type 2 diabetes, ear infections, obesity, and some childhood cancers, increased likelihood of a smaller thymus, and an increased risk of sudden infant death syndrome (SIDS) (LLLI, n.d.; Jackson & Nazar, 2019; Alm, 2002; Thompson et al., 2017).
• The mother who does not breastfeed has an increased risk of breast and ovarian cancer, earlier menopause age, decreased bone strength and size, non-fatty liver disease, and coronary artery disease (Wiklund et al., 2011; Enger et al., 1997; Langton et al., 2020; Ajmera et al., 2019; Rajaei et al., 2002).

Treatment of each COVID-19 positive mother and her baby should be considered on a case-by-case basis. Separation is not suggested by the WHO, the UN, UNICEF, the ABM or LLLI. All of these risks should be carefully considered and shared with the mother to help her make an informed decision whenever separation is being proposed. 

Footnotes

‌(A) The stress hyporesponsive period (SHRP)—a period during which the body is much less reactive to stessors—has been modeled in rats and may also be present in humans.  One thing that overarches this lowered response to stress is separation of the pup from the dam—the pup is extremely stressed by separation from its mother and the ill effects of separation are even greater from earlier separations than later (Lupien et al., 2009). Furthermore, primate studies also show that mother-baby separations affect the HPA axis months or years later (Lupien et al., 2009).  The primate studies also show “heightened fear behavior, exaggerated startle responses, hippocampal changes …, and atypical development of prefrontal regions involved in emotion and behavior control” (Lupien et al., 2009). Lupien et al further notes that human studies suggest that the HPA axis is buffered by parents and social contact in the first year of life.  With all of this in mind, separating the newborn from the mother might be one of the most stressful things in a hospital protocol that can be done to the child.

‌(B) Crenshaw explains,

“Disrupting or delaying skin-to-skin care may suppress a newborn’s innate protective behaviors, lead to behavioral disorganization, and make self-attachment and breastfeeding more difficult. Lack of skin-to-skin care and early separation also may disturb maternal–infant bonding, reduce the mother’s affective response to her baby, and have a negative effect on maternal behavior.” (Crenshaw, 2014 )

(C) These immune factors include leukocytes (granulocytes, monocytes/macrophages, and lymphocytes [T-cells, NK cells, and antibody-producing B cells]), stem cells of hematopoietic and mammary gland origin (shown to differentiate), sigA, casein, serum albumin, growth factors (EGF, BDNF, GDNF, CNTF, IGF-I, IGF-II, VEGF), Epo, lysozyme, lactoferrin, nucleotides, alpha lactalbumin, tryptophan, calcitonin, miRNA, pre-and probiotics including oligosaccharides, lipase, amino acids, lactose, fatty acids, vitamins, cytokines, chemokines, cytokine inhibitors, metabolic hormones, mucins, and others (Ballard & Ardythe, 2013; Field, 2005; Jantscher-Krenn & Bode, 2012; Ray et al., 2019; Butler, 1979).

Case Review of Infants Born to COVID-19 Positive Mothers (Part 2)

What do the case reports of mother-infant pairs with SARS-CoV-2 involvement tell us?

• Dong et al. (2020) published a single case report of possible vertical transmission from mother to infant. Yet what they found to denote infection was antibodies in the baby’s blood: elevated IgG and IgM antibodies. All 5 reverse transcription-polymerase chain reaction (RT-PCR) nasal swabs for SARS-CoV-2 came back negative (from 2 hours to 16 days). Baby was born via cesarean section and was not allowed contact with the mother so I believe the likelihood of antepartum transmission via close contact with the mother is low.
• Zeng et al. looked at six babies born to mothers with COVID-19 who were born via cesarean (mothers wore masks). They found elevated IgM antibodies in two infants, elevated IgG in five, RT-PCR was negative in all, and none of the infants had any symptoms (H. Zeng et al., 2020).
• Chen et al. looked at nine dyads whose mothers tested positive for COVID-19 (via RT-PCR) and had cesarean sections. Of the six babies with data, amniotic fluid, cord blood, neonatal throat swab, and human milk samples were tested for SARS-CoV-2, and results were negative for the virus pointing to NO vertical transmission of the virus (Chen et al., 2020).
• The latest report by L. Zeng et al., is of 33 infants born to COVID-19 positive mothers (L. Zeng et al., 2020). Three infants became ill or were born ill and tested positive. The sickest patient (who also recovered) was 31 weeks gestation so at least part of the issues and severity were likely due to gestational age. All three were born via cesarean. Vertical transmission cannot be ruled out (L. Zeng et al., 2020). No patients were tested on day one. Data on IgG, amniotic fluid, etc. is not reported.
  • Patient One: on day two lethargy and fever. Swabs positive on days two and four, negative on day six (L. Zeng et al., 2020).
  • Patient Two, presented ill, also had meconium staining: swabs positive days two and four, negative on day six (L. Zeng et al., 2020).
  • Patient Three: born at 31 weeks, resuscitation required, suspected sepsis, positive on days two and four, negative on day seven.
• Egloff et al found that because babies were not tested at birth (earliest positive is 16 hours) vertical transmission cannot be proved or ruled out (Egloff et al., 2020).

Whether infection is in utero or postpartum, a baby will receive his mother’s antibodies, and perhaps start to produce his/her own in some cases (possibly indicated by the presence of IgM in a few of the babies). Being close to mother with all the many benefits that affords as well as the antiviral powerhouse of breast milk seems much better for reducing viral load and infectivity and increasing overall health (or maintaining a baseline of health) than separation. Also, since loneliness is proven to negatively affect health (by Kiecolt-Glaser et al., 1984), reducing the effective action of cellular immunity via separation (for mother and baby) seems a strong negative (immunocompromising) choice to make in the face of a pandemic.

Let’s not separate babies and mothers unless the great risks outlined in Part 1 are truly outweighed by the benefit of separating them. What is the perceived benefit?  What is the actual benefit? As Leaders, we need to share comprehensive information with parents and give mothers the opportunity to make a fully informed decision.

 

NOTE

The content of this article was last edited 3rd of June, 2020. Please keep in mind that research and recommendations around SARS-CoV-2 are constantly evolving.

Dena Duran has a long interest in the health and science fields and is honored to be a part of La Leche League (since 2013), helping mothers and babies in New York City and in Idaho, USA.  She is an Associate Professional Liaison for LLL New York and is the newest representative to the US Breastfeeding Committee for LLL Alliance for Breastfeeding Education.  Dena is thankful for her loving, supportive husband, Jason and their two wonderful girls, Sophia and Sabrina. Contact Dena at lll.denaduran@gmail.com

 

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