Breastfeeding, Corona Virus Infection, Neonatal Infection, Pregnancy Related
Conditions
Brief summary
This national study will recruit expectant mothers with and without positive nasopharyngeal swabs for SARS-CoV-2, and aims to determine the seroepidemiology of SARS-CoV-2 amongst expectant mothers and their infants in the U.K.
Interventions
None listed
Sponsors
St George's, University of London
Study design
Observational model
CASE_CONTROL
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Signed informed consent form * Any woman pregnant in selected hospitals in England who has no signs or symptoms of COVID-19 disease during pregnancy and is rtPCR negative at delivery * Any woman pregnant in any hospital in England who tests positive by rtPCR at any point during pregnancy from 24 weeks gestation onwards, regardless of signs and symptoms
Exclusion criteria
* If the pregnant woman is under 18 years in prison or unable to make an informed consent for other reasons (e.g. learning difficulties, language barriers)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Antibody Concentrations in Maternal Blood in Pregnant Women in England | Delivery | Antibody concentrations in maternal blood in pregnant women in England: ADCD-S values reported |
| Antibody Concentrations in Cord/Infant Blood at Delivery | Delivery | Cord blood was tested to determine infant antibody levels; where a cord blood sample was not available, a blood sample was taken from the infant instead. ADCD-S assay results are presented. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of Participants With Breastmilk Samples Positive for Antibodies Specific to SARS-CoV-2 | At birth | Number of participants with breastmilk samples positive for antibodies specific to SARS-CoV-2 |
| Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Blood at Delivery | Delivery | — |
| Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Secretions at Delivery | Delivery | — |
| Breastmilk Samples That Are rtPCR Positive | Delivery | — |
| Placental Samples That Are rtPCR Positive | Delivery | — |
| Number of Participants in Whose Placental Sample the Virus Can be Grown in Vitro | Delivery | — |
| Number of Participants in Whose Breast Milk Sample the Virus Can be Grown in Vitro | Delivery | — |
| Number of Mother-baby Pairs in Whom the Virus Can be Grown in Vitro | 6 weeks post delivery | — |
Countries
United Kingdom
Participant flow
Pre-assignment details
Participants had their antibodies against SARS-CoV-2 tested prior to assignment of a group.
Participants by arm
| Arm | Count |
|---|---|
| Exposed Expectant mothers with a positive nasopharyngeal swab for SARS-CoV-2 at any point during pregnancy from 24 weeks gestation regardless of antibody status. | 173 |
| Unexposed Expectant mothers with a negative nasopharyngeal swab for SARS-CoV-2 at any point during pregnancy from 24 weeks gestation. | 627 |
| Vaccinated Expectant mothers with a negative nasopharyngeal swab for SARS-CoV-2 at any point during pregnancy from 24 weeks gestation who received a vaccine against SARS-CoV-2 prior to delivery. | 43 |
| Vaccinated and Exposed Expectant mothers with a positive nasopharyngeal swab for SARS-CoV-2 at any point during pregnancy from 24 weeks gestation who also received a vaccine against SARS-CoV-2 prior to delivery. | 38 |
| Total | 881 |
Baseline characteristics
| Characteristic | Exposed | Unexposed | Vaccinated | Vaccinated and Exposed | Total |
|---|---|---|---|---|---|
| Age, Continuous | 33.0 years | 31.0 years | 34.0 years | 33.5 years | 32.0 years |
| Race/Ethnicity, Customized Asian/Asian British | 9 Participants | 54 Participants | 8 Participants | 4 Participants | 75 Participants |
| Race/Ethnicity, Customized Black African/Caribbean/British | 4 Participants | 20 Participants | 0 Participants | 0 Participants | 24 Participants |
| Race/Ethnicity, Customized Mixed/Multiple | 1 Participants | 12 Participants | 0 Participants | 0 Participants | 13 Participants |
| Race/Ethnicity, Customized Not Stated | 66 Participants | 33 Participants | 1 Participants | 9 Participants | 109 Participants |
| Race/Ethnicity, Customized Other | 8 Participants | 12 Participants | 2 Participants | 1 Participants | 23 Participants |
| Race/Ethnicity, Customized White | 85 Participants | 496 Participants | 32 Participants | 24 Participants | 637 Participants |
| Sex: Female, Male Female | 173 Participants | 627 Participants | 43 Participants | 38 Participants | 881 Participants |
| Sex: Female, Male Male | 0 Participants | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk |
|---|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 173 | 0 / 627 | 0 / 43 | 0 / 38 |
| other Total, other adverse events | 0 / 173 | 0 / 627 | 0 / 43 | 0 / 38 |
| serious Total, serious adverse events | 0 / 173 | 0 / 627 | 0 / 43 | 0 / 38 |
Outcome results
Primary
Antibody Concentrations in Cord/Infant Blood at Delivery
Cord blood was tested to determine infant antibody levels; where a cord blood sample was not available, a blood sample was taken from the infant instead. ADCD-S assay results are presented.
Time frame: Delivery
Population: Number of participants analysed represents all those for whom a sample was received that was sufficient for analysis with the assay.
| Arm | Measure | Value (GEOMETRIC_MEAN) |
|---|---|---|
| Exposed | Antibody Concentrations in Cord/Infant Blood at Delivery | 35.9 CAU/mL |
| Unexposed | Antibody Concentrations in Cord/Infant Blood at Delivery | 7.5 CAU/mL |
| Vaccinated | Antibody Concentrations in Cord/Infant Blood at Delivery | 83.9 CAU/mL |
| Vaccinated and Exposed | Antibody Concentrations in Cord/Infant Blood at Delivery | 549.0 CAU/mL |
Primary
Antibody Concentrations in Maternal Blood in Pregnant Women in England
Antibody concentrations in maternal blood in pregnant women in England: ADCD-S values reported
Time frame: Delivery
| Arm | Measure | Value (GEOMETRIC_MEAN) |
|---|---|---|
| Exposed | Antibody Concentrations in Maternal Blood in Pregnant Women in England | 37.2 CAU/ml |
| Unexposed | Antibody Concentrations in Maternal Blood in Pregnant Women in England | 7.2 CAU/ml |
| Vaccinated | Antibody Concentrations in Maternal Blood in Pregnant Women in England | 80.3 CAU/ml |
| Vaccinated and Exposed | Antibody Concentrations in Maternal Blood in Pregnant Women in England | 590.5 CAU/ml |
Secondary
Breastmilk Samples That Are rtPCR Positive
Time frame: Delivery
Population: No samples were received which were sufficient to allow PCR testing after antibody testing.
Secondary
Number of Mother-baby Pairs in Whom the Virus Can be Grown in Vitro
Time frame: 6 weeks post delivery
Population: No paired samples proceeded to in vitro culture due to lack of PCR positivity.
Secondary
Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Blood at Delivery
Time frame: Delivery
Population: No sufficient samples were received to enable rtPCR testing of mother and baby within a pair after sample testing for the primary outcome.
Secondary
Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Secretions at Delivery
Time frame: Delivery
Population: All pairs for which a neonatal sample was received for the delivery timepoint were analysed. No delivery secretion samples were taken from neonates in the Unexposed group as per the study protocol.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Exposed | Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Secretions at Delivery | 0 Number of mother-infant pairs |
| Unexposed | Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Secretions at Delivery | 0 Number of mother-infant pairs |
| Vaccinated | Number of Mother-infant Pairs Who Are Both rtPCR Positive for SARS-CoV-2 in Secretions at Delivery | 0 Number of mother-infant pairs |
Secondary
Number of Participants in Whose Breast Milk Sample the Virus Can be Grown in Vitro
Time frame: Delivery
Population: No breastmilk samples were PCR positive, therefore none proceeded to in vitro culture.
Secondary
Number of Participants in Whose Placental Sample the Virus Can be Grown in Vitro
Time frame: Delivery
Population: All PCR placental samples were negative at delivery, except for one swab which was determined to have likely been contaminated in the delivery room. As all other samples were negative, none proceeded to in vitro culture.
Secondary
Number of Participants With Breastmilk Samples Positive for Antibodies Specific to SARS-CoV-2
Number of participants with breastmilk samples positive for antibodies specific to SARS-CoV-2
Time frame: At birth
Population: Most participants did not provide a breastmilk sample of sufficient quantity for analysis.
| Arm | Measure | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|
| Unexposed | Number of Participants With Breastmilk Samples Positive for Antibodies Specific to SARS-CoV-2 | 0 Participants |
| Vaccinated | Number of Participants With Breastmilk Samples Positive for Antibodies Specific to SARS-CoV-2 | 16 Participants |
| Vaccinated and Exposed | Number of Participants With Breastmilk Samples Positive for Antibodies Specific to SARS-CoV-2 | 0 Participants |
Secondary
Placental Samples That Are rtPCR Positive
Time frame: Delivery
Population: The population numbers reflect the samples received which were suitable for rtPCR testing. No placental samples were received from participants in the Unexposed or Vaccinated arms, so these were not analysed.
| Arm | Measure | Value (NUMBER) |
|---|---|---|
| Exposed | Placental Samples That Are rtPCR Positive | 1 No. of Placental Samples rtPCR positive |
| Unexposed | Placental Samples That Are rtPCR Positive | 0 No. of Placental Samples rtPCR positive |