Can COVID-19 be passed on to my (un)born child?
Pregnant mothers who test positive for SARS-CoV-2 are concerned that they may transmit the viral infection to their baby during pregnancy or after birth. After birth, there is a risk the virus can be transmitted during breastfeeding or normal care, but this risk can be minimized with simple precautions. Reassuringly, most babies do not seem to suffer serious symptoms if infection does occur.
The questions that might be asked:
- What is the risk my baby gets COVID-19 during pregnancy or childbirth
- Can my baby get COVID-19 if I breastfeed?
- What are the precautions the hospital takes for pregnant women who are admitted to the hospital
1. What is the risk my baby gets COVID-19 during pregnancy or childbirth?
Short answer: pregnant women do not appear to be at high risk of passing on SARS-CoV-2 to their unborn child, but because this a relatively new virus, we only have good data for women who have been infected later in their pregnancy.
The placenta separates the maternal and fetal blood circulations but allows exchange of nutrients between them to support fetal growth. It is therefore possible that viruses in the mother’s blood can cross into the baby; this is known as ‘vertical transmission’. In fact the placenta is very good at preventing this – very few viral or bacterial infections can cross the placenta from mother to baby during pregnancy.
Most pregnancies that have been evaluated so far involved women infected were in their third trimester, with women checked into the hospital shortly before the expected delivery. Mothers testing positive for SARS-CoV-2 then had their babies tested immediately after birth. These initial studies reported very low rates of vertical transmission (in late pregnancy) [1,2,3]. These involved women who were infected in the third trimester of pregnancy, and relatively small numbers of women. A more recent review of published reports of pregnancy outcomes shows that 8% out of 313 pregnant women who tested positive for COVID-19, might have transmitted the virus vertically . Similarly, the Royal College of Obstetricians & Gynaecologists in the UK reports 5% (12) of 213 infants from infected mothers, were found to carry the virus, of which were 2.5% (6 infants) tested positive within the first 12h of birth, whereas the other 2.5% (6 infants) had a later infection (time of test is not mentioned)  The observation of diseases was mild and not severe .
It is unclear if transmission rate from mother to fetus differs in the first or second trimester . Larger studies are now underway to determine whether vertical transmission occurs at these earlier stages of pregnancy. At this time the possibility of vertical transmission cannot be excluded.
2. Can my baby get COVID-19 if I breastfeed?
Short answer: breast milk appears to contain negligible levels of SARS-CoV-2 so provided normal hygiene is followed, risks are low. The appropriate hygiene for the expression of breast milk needs to be practiced, such as disinfection of hands, breasts and wearing surgical masks [1,2].
An additional concern is whether mothers suffering from COVID-19, can transmit the virus to their baby after birth by breastfeeding or normal caring. At time of birth, either by vaginal or cesarean delivery, it is recommended that infants should be placed in isolation because of the unknown risks . And that infants need to be kept at a distance from their positive-tested mothers.
Nevertheless, mothers are still encouraged to continue breastfeeding through expression of breast milk and giving it to their newborn via bottle feeding, since breast milk samples of positive tested COVID-19 mothers appeared have no signs of SARS-CoV-2 . But, appropriate hygiene for the expression of breast milk needs to be practiced, including disinfection of hands, breasts and wearing surgical masks [1,2].
3. What are the consequences for partners, midwives and medical staff for mothers who test positive?
Short answer: because of the risk of spreading SARS-CoV-2 in hospitals, all normal precautions should be taken to prevent infection of other hospital uses and staff. Pregnant women going into labor and admitted to the hospital need to be tested for COVID-19.
Currently all women admitted to maternity hospitals are recommended for testing for SARS-CoV-2. The majority that test positive were found to be asymptomatic and show no obvious symptoms . This can pose a potential threat for hospital staff, and birth partners as well as for other mothers and babies on maternity wards, Therefore, it is important to test pregnant women, who are admitted into the labor unit to protect staff, family and the newborn [1,2,7,8].
 Boeling RC, Manuck T, Oliver EA, et al.Labor and delivery guide for COVID-19. American Journal of Obstetrics & Gynecology MFM 2020:100110. doi: https://doi.org/10.1016/j.ajogmf.2020.100110
 Breslin N, Baptiste C, Gyamfi-Bannerman C, et al. COVID-19 infection among asymptomatic and symptomatic pregnant women: Two weeks of confirmed presentations to an affiliated pair of New York City hospitals. American Journal of Obstetrics and Gynecology MFM 2020;Epub ahead of print
 Chen H, Guo J, Wang C, et al. Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records. Lancet 2020;395(10226):809-15. doi: 10.1016/s0140-6736(20)30360-3 [published Online First: 2020/03/11]
 Gajbhiye R, Modi D, Mahale S. Pregnancy outcomes, Newborn complications and Maternal-Fetal Transmission of SARS-CoV-2 in women with COVID-19: A systematic review of 441 cases. Preprint accessed via https://www.medrxiv.org/content/10.1101/2020.04.11.20062356v2 on 24 May 2020.
 Royal College of Obstetricians and Gynaecologists and The Royal College of Midwives. Coronavirus (COVID-19) Infection in Pregnancy: Information for healthcare professionals. In: Royal College of Obstetricians and Gynaecologists, ed. London, 2020.
 Knight M, Bunch K,Vousden N, et al. Characteristics and outcomes of pregnant women hospitalised with confirmed SARS-CoV-2 infection in the UK: a national cohort study using the UK Obstetric Surveillance System (UKOSS). 2020 [Available from: https://www.npeu.ox.ac.uk/downloads/files/ukoss/annual-reports/ UKOSS%20COVID-19%20Paper%20pre-print%20draft%2011-05-20.pdf] accessed 24 May 2020.
 Dong L, Tian J, He S, et al. Possible Vertical Transmission of SARS-CoV-2 From an Infected Mother to Her Newborn. JAMA 2020 doi: 10.1001/jama.2020.4621
 Zeng H, Xu C, Fan J, et al. Antibodies in Infants Born to Mothers With COVID-19 Pneumonia. JAMA 2020 doi: 10.1001/jama.2020.4861