OP03.03: Factors influencing transplacental transmission of IgG antibodies providing newborns with maternal passive immunity after COVID-19 in pregnancy
Related Research units
Abstract
Objectives
Mothers convey passive immunity to their newborns through the transplacental transfer of IgG antibodies. We aimed to evaluate the influence of specific factors modulating the transplacental IgG transfer rate (TPTR) in 57 mother/neonate dyads with maternal COVID-19 infection in pregnancy.
Methods
57 women with a COVID-19 infection in pregnancy proven by positive RT-PCR in a nasopharyngeal swab were included in this prospective cohort study. At birth, a venous blood sample was obtained from the mother. Cord blood was taken from the umbilical cord at childbirth after cord clamping. Commercially available high-throughput COVID-19 immunoassays were used for quantitative detection of IgG antibody against COVID-19 spike protein (Liasion Xl, Diasorine).
Results
21 women showed seroconversion at delivery, 36 women had no COVID-19 IgG antibodies in maternal or cord blood at delivery. A lack of antibodies was associated with a short infection-to-delivery interval (<21 days) or asymptomatic or mild infection. Median gestational age at delivery was 39.1 (range 33.4-42.0) weeks, median infection-to-delivery interval was 131 (range 33-261) days, including women in all trimesters. The transplacental transfer ratio of IgG was 139% (range 56-200%). There was positive correlation between the infection-to-delivery interval and the TPTR. The pulsatility index in the uterine arteries (PI) and the maternal body-mass-index (BMI) were negatively correlated with the TPTR.
Conclusions
COVID-19 IgG antibodies after COVID-19 infection in pregnancy seem to wane rather rapidly. Asymptomatic or mild infection is often associated with a lack of maternal antibodies at delivery leading to a missing passive immunity of the newborn. Several factors (e.g. PI in the uterine arteries, maternal BMI and the infection-to-delivery interval) might influence the transplacental transfer of COVID-19 specific antibodies but need to be evaluated in further larger cohort studies.
Mothers convey passive immunity to their newborns through the transplacental transfer of IgG antibodies. We aimed to evaluate the influence of specific factors modulating the transplacental IgG transfer rate (TPTR) in 57 mother/neonate dyads with maternal COVID-19 infection in pregnancy.
Methods
57 women with a COVID-19 infection in pregnancy proven by positive RT-PCR in a nasopharyngeal swab were included in this prospective cohort study. At birth, a venous blood sample was obtained from the mother. Cord blood was taken from the umbilical cord at childbirth after cord clamping. Commercially available high-throughput COVID-19 immunoassays were used for quantitative detection of IgG antibody against COVID-19 spike protein (Liasion Xl, Diasorine).
Results
21 women showed seroconversion at delivery, 36 women had no COVID-19 IgG antibodies in maternal or cord blood at delivery. A lack of antibodies was associated with a short infection-to-delivery interval (<21 days) or asymptomatic or mild infection. Median gestational age at delivery was 39.1 (range 33.4-42.0) weeks, median infection-to-delivery interval was 131 (range 33-261) days, including women in all trimesters. The transplacental transfer ratio of IgG was 139% (range 56-200%). There was positive correlation between the infection-to-delivery interval and the TPTR. The pulsatility index in the uterine arteries (PI) and the maternal body-mass-index (BMI) were negatively correlated with the TPTR.
Conclusions
COVID-19 IgG antibodies after COVID-19 infection in pregnancy seem to wane rather rapidly. Asymptomatic or mild infection is often associated with a lack of maternal antibodies at delivery leading to a missing passive immunity of the newborn. Several factors (e.g. PI in the uterine arteries, maternal BMI and the infection-to-delivery interval) might influence the transplacental transfer of COVID-19 specific antibodies but need to be evaluated in further larger cohort studies.
Bibliographical data
| Original language | English |
|---|---|
| ISSN | 0960-7692 |
| DOIs | |
| Publication status | Published - 14.10.2022 |
