Interpregnancy Stability of the First-Trimester Uterine Artery Pulsatility Index: A Within-Woman Comparison with PAPP-A and Free β-hCG in 864 Women.
- 1Department of Obstetrics and Gynecology, Faculty of Medicine, Victor Babeș University of Medicine and Pharmacy, 300041 Timișoara, Romania.
- 2Maternal-Fetal Medicine Center, 300331 Timișoara, Romania.
Abstract
Background/Objectives: First-trimester screening combines a haemodynamic marker, the uterine artery pulsatility index (UtA-PI), with two serum markers, pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotropin (free β-hCG). For the serum markers, it is known that the value measured in one pregnancy correlates with the value measured in the same woman's next pregnancy. For UtA-PI, only decreases in the mean value in second pregnancies have been reported. This study quantifies how much of a woman's standardised UtA-PI persists from one pregnancy to the next and compares this persistence with that of the serum markers measured in the same woman. Methods: We performed a retrospective longitudinal analysis of the screening database of a single foetal medicine unit (August 2010-August 2026). Among 8925 eligible singleton pregnancies, 864 women were screened in two or more pregnancies (1757 pregnancies; 893 pairs of successive pregnancies; median interval 2.9 years, range 0.4-10.7 years). Marker values, expressed as multiples of the median (MoM) and log-transformed, were analysed with random-intercept models that split the total variation into a component between women and a component between the pregnancies of the same woman. The intraclass correlation coefficient (ICC), the fraction of the variation that lies between women, was estimated with bootstrap confidence intervals. Results: The ICC was 0.349 (95% confidence interval 0.280-0.412) for PAPP-A, 0.339 (0.274-0.397) for UtA-PI and 0.392 (0.290-0.478) for free β-hCG; that is, about one-third of the variation in each marker lay between women and about two-thirds between the pregnancies of the same woman. Adjustment for maternal age, body mass index, parity, smoking, gestational age, calendar time, biochemical analyser and examiner did not change the estimates (0.350 and 0.352). No weakening of the between-pregnancy correlation with a longer interval was detected (interaction p = 0.698 and 0.153), although statistical power was limited for the longest intervals. UtA-PI was lower in the next pregnancy by 6.3% on average (95% confidence interval 4.5-8.2%), whereas PAPP-A did not change. A previous PAPP-A below 0.4 MoM recurred in 17.4% of next pregnancies, and a previous UtA-PI above the 95th centile in 6%. Conclusions: Two distinct phenomena coexist in UtA-PI: a systematic fall at the population level in the next pregnancy, and a modest persistence of the individual value. Approximately one-third of the variation in UtA-PI reflects persistent differences between women-no more than for the serum markers-whereas two-thirds arises between the pregnancies of the same woman. A previous value carries some information about the next pregnancy but cannot replace a new measurement.
Related
- Deep learning reconstruction-applied PROPELLER diffusion-weighted imaging in uterine malignancies: a comparison study with MUSE
- Contraceptive knowledge and interpregnancy interval among women attending a tertiary care hospital in Malaysia
- Increasing paced heart rate reduces cerebral pulsatility
- Prognostic value of pulmonary artery pulsatility index for perioperative adverse cardiovascular events in patients undergoing surgery for mitral regurgitation
- Imaging-guided shortened interpregnancy interval following myomectomy in China: protocol for a multicentre prospective randomised controlled trial
BibTeX
@article{mureșan2026interpregnancy,
title = {{Interpregnancy Stability of the First-Trimester Uterine Artery Pulsatility Index: A Within-Woman Comparison with PAPP-A and Free β-hCG in 864 Women.}},
author = {Maria Cezara Mureșan and Marius Bogdan Mureșan and Dan Dumitrașcu Biriș and Zoran Laurențiu Popa},
journal = {Diagnostics (Basel, Switzerland)},
year = {2026},
month = sep,
doi = {10.3390/diagnostics16193108},
url = {https://europepmc.org/article/MED/42882262},
note = {CC BY},
}
RIS
TY - JOUR
TI - Interpregnancy Stability of the First-Trimester Uterine Artery Pulsatility Index: A Within-Woman Comparison with PAPP-A and Free β-hCG in 864 Women.
AU - Maria Cezara Mureșan
AU - Marius Bogdan Mureșan
AU - Dan Dumitrașcu Biriș
AU - Zoran Laurențiu Popa
PY - 2026
DA - 2026/09/24
JO - Diagnostics (Basel, Switzerland)
DO - 10.3390/diagnostics16193108
UR - https://europepmc.org/article/MED/42882262
AB - Background/Objectives: First-trimester screening combines a haemodynamic marker, the uterine artery pulsatility index (UtA-PI), with two serum markers, pregnancy-associated plasma protein A (PAPP-A) and free β-human chorionic gonadotropin (free β-hCG). For the serum markers, it is known that the value measured in one pregnancy correlates with the value measured in the same woman's next pregnancy. For UtA-PI, only decreases in the mean value in second pregnancies have been reported. This study quantifies how much of a woman's standardised UtA-PI persists from one pregnancy to the next and compares this persistence with that of the serum markers measured in the same woman. Methods: We performed a retrospective longitudinal analysis of the screening database of a single foetal medicine unit (August 2010-August 2026). Among 8925 eligible singleton pregnancies, 864 women were screened in two or more pregnancies (1757 pregnancies; 893 pairs of successive pregnancies; median interval 2.9 years, range 0.4-10.7 years). Marker values, expressed as multiples of the median (MoM) and log-transformed, were analysed with random-intercept models that split the total variation into a component between women and a component between the pregnancies of the same woman. The intraclass correlation coefficient (ICC), the fraction of the variation that lies between women, was estimated with bootstrap confidence intervals. Results: The ICC was 0.349 (95% confidence interval 0.280-0.412) for PAPP-A, 0.339 (0.274-0.397) for UtA-PI and 0.392 (0.290-0.478) for free β-hCG; that is, about one-third of the variation in each marker lay between women and about two-thirds between the pregnancies of the same woman. Adjustment for maternal age, body mass index, parity, smoking, gestational age, calendar time, biochemical analyser and examiner did not change the estimates (0.350 and 0.352). No weakening of the between-pregnancy correlation with a longer interval was detected (interaction p = 0.698 and 0.153), although statistical power was limited for the longest intervals. UtA-PI was lower in the next pregnancy by 6.3% on average (95% confidence interval 4.5-8.2%), whereas PAPP-A did not change. A previous PAPP-A below 0.4 MoM recurred in 17.4% of next pregnancies, and a previous UtA-PI above the 95th centile in 6%. Conclusions: Two distinct phenomena coexist in UtA-PI: a systematic fall at the population level in the next pregnancy, and a modest persistence of the individual value. Approximately one-third of the variation in UtA-PI reflects persistent differences between women-no more than for the serum markers-whereas two-thirds arises between the pregnancies of the same woman. A previous value carries some information about the next pregnancy but cannot replace a new measurement.
SN - 2075-4418
ER -