TY - JOUR

T1 - Plasma fibulin-1 levels during pregnancy and delivery: a longitudinal observational study

AU - Orvik, Astrid Bakke

AU - Andersen, Malene Rohr

AU - Pedersen, Lise

AU - Ritz, Christian

AU - Stender, Steen

AU - Szecsi, Pal Bela

N1 - © 2021. The Author(s).

PY - 2021

Y1 - 2021

N2 - Background: Fibulin-1 is an extracellular matrix protein expressed at high levels in the placenta. Elevated circulating fibulin-1 have been observed in women with severe pre-eclampsia, whereas low levels have been found in the fetal membranes, prior to membrane rupture. The aim of the study was primarily to evaluate plasma fibulin-1 during expected normal pregnancy and delivery, and secondarily to explore fibulin-1 levels in women developing pre-eclampsia or preterm premature rupture of fetal membranes (PPROM).Methods: From the historical longitudinal cohort originally consisting of 801 healthy Danish women with a singleton pregnancy, 128 women (632 samples) were selected. Of these, 107 women had normal pregnancies, nine experienced PPROM, and 12 pre-eclampsia. All samples were analyzed for fibulin-1, and levels were compared with blood donors. Differences in mean fibulin-1 between groups were estimated using a linear mixed model.Results: The mean concentration of fibulin-1 in 120 blood donors was 15.7 µg/mL, (25th-75th-percentiles, 12.3-18.2), with no significant difference in groups stratified by gender or age. Compared to baseline levels in week 12-20, fibulin-1 levels increased significantly from week 29-34 (estimated difference, 5.6 µg/mL; standard error, 1.7; p < 0.001) and 35-42 (12.5 µg/mL; 1.6; p < 0.001) and normalized after birth. The decrease at delivery tended to be more pronounced after elective (-7.0 µg/mL; 2.3; p = 0.002) and emergency (-5.6 µg/mL; 2.9; p = 0.05) cesarean section than after vaginal delivery (reference group). Women who developed PPROM had lower fibulin-1 levels throughout their pregnancies (-11.6 µg/mL; 4.2; p = 0.006). We did not observe a correlate between late pre-eclampsia and fibulin-1 (-0.2 µg/mL; 3.0; p = 0.9).Conclusions: Fibulin-1 was above non-pregnant levels at week 12 and increased significantly throughout pregnancy. We observed an association between low levels of fibulin-1 and PPROM. Further studies are needed to examine if fibulin-1 could serve as biomarker for the risk of PPROM. However, its role in late preeclampsia is doubtful.Trial registration: The study was conducted in accordance with the Declaration of Helsinki. The participants provided written informed consent, including storage for future use. The study was approved on July 18, 2005 by The Danish National Committee on Bioethics (No. KA 05065 and S-20,090,061) and the Danish Data Protection Agency.

AB - Background: Fibulin-1 is an extracellular matrix protein expressed at high levels in the placenta. Elevated circulating fibulin-1 have been observed in women with severe pre-eclampsia, whereas low levels have been found in the fetal membranes, prior to membrane rupture. The aim of the study was primarily to evaluate plasma fibulin-1 during expected normal pregnancy and delivery, and secondarily to explore fibulin-1 levels in women developing pre-eclampsia or preterm premature rupture of fetal membranes (PPROM).Methods: From the historical longitudinal cohort originally consisting of 801 healthy Danish women with a singleton pregnancy, 128 women (632 samples) were selected. Of these, 107 women had normal pregnancies, nine experienced PPROM, and 12 pre-eclampsia. All samples were analyzed for fibulin-1, and levels were compared with blood donors. Differences in mean fibulin-1 between groups were estimated using a linear mixed model.Results: The mean concentration of fibulin-1 in 120 blood donors was 15.7 µg/mL, (25th-75th-percentiles, 12.3-18.2), with no significant difference in groups stratified by gender or age. Compared to baseline levels in week 12-20, fibulin-1 levels increased significantly from week 29-34 (estimated difference, 5.6 µg/mL; standard error, 1.7; p < 0.001) and 35-42 (12.5 µg/mL; 1.6; p < 0.001) and normalized after birth. The decrease at delivery tended to be more pronounced after elective (-7.0 µg/mL; 2.3; p = 0.002) and emergency (-5.6 µg/mL; 2.9; p = 0.05) cesarean section than after vaginal delivery (reference group). Women who developed PPROM had lower fibulin-1 levels throughout their pregnancies (-11.6 µg/mL; 4.2; p = 0.006). We did not observe a correlate between late pre-eclampsia and fibulin-1 (-0.2 µg/mL; 3.0; p = 0.9).Conclusions: Fibulin-1 was above non-pregnant levels at week 12 and increased significantly throughout pregnancy. We observed an association between low levels of fibulin-1 and PPROM. Further studies are needed to examine if fibulin-1 could serve as biomarker for the risk of PPROM. However, its role in late preeclampsia is doubtful.Trial registration: The study was conducted in accordance with the Declaration of Helsinki. The participants provided written informed consent, including storage for future use. The study was approved on July 18, 2005 by The Danish National Committee on Bioethics (No. KA 05065 and S-20,090,061) and the Danish Data Protection Agency.

KW - Faculty of Science

KW - Fibulin

KW - Humans

KW - Plasma

KW - Postpartum

KW - Pre-eclampsia

KW - Pregnancy

KW - Preterm premature rupture of membranes

U2 - 10.1186/s12884-021-04110-y

DO - 10.1186/s12884-021-04110-y

M3 - Journal article

C2 - 34535108

VL - 21

JO - B M C Pregnancy and Childbirth

JF - B M C Pregnancy and Childbirth

SN - 1471-2393

M1 - 629

ER -