A longitudinal study of umbilical artery Doppler waveforms in normal pregnancy: analysis using Laplace transform techniques

British Journal of Obstetrics and Gynaecology
K J BrackleyP C Rubin

Abstract

To analyse umbilical artery Doppler waveforms using the Laplace transform analysis technique, an alternative method of waveform shape analysis, and to determine the normal ranges for the variables of this technique throughout normal pregnancy. A prospective longitudinal study. Department of Obstetrics and Gynaecology, Nottingham University Hospital. A cohort of 17 healthy women investigated every four weeks from the end of the first trimester until term. Umbilical artery Doppler signals were recorded and analysed using the Laplace transform analysis technique. The median and interquartile ranges for each variable were determined and serial changes during pregnancy described. Vessel wall tone decreases in the umbilical artery at the beginning of the second trimester. Alpha, the variable related to upstream flow conditions, also decreases at this stage of pregnancy but values are then comparatively stable from 24 weeks of gestation until term. A fall in downstream resistance within the fetoplacental circulation during pregnancy is detected using the C-coefficient. Real pole appears to be of no value in the assessment of downstream resistance to flow in the fetus. The normal ranges for the Laplace transform analysis variables have...Continue Reading

References

Oct 23, 1992·European Journal of Obstetrics, Gynecology, and Reproductive Biology·W KünzelT Colling
Sep 1, 1992·American Journal of Obstetrics and Gynecology·J W WladimiroffT Stijnen
Jul 1, 1991·Journal of Clinical Ultrasound : JCU·D Arduini, G Rizzo
Oct 1, 1991·American Journal of Obstetrics and Gynecology·G Rizzo, D Arduini
Feb 15, 1985·American Journal of Obstetrics and Gynecology·A FleischerG Randolph
Jun 1, 1985·British Journal of Obstetrics and Gynaecology·R L Erskine, J W Ritchie
Apr 1, 1984·American Journal of Obstetrics and Gynecology·H SchulmanP Blattner
Jan 1, 1980·Ultrasound in Medicine & Biology·R Skidmore, J P Woodcock
Jan 1, 1980·Ultrasound in Medicine & Biology·R SkidmoreP N Wells

❮ Previous
Next ❯

Citations

Feb 23, 2019·American Journal of Physiology. Heart and Circulatory Physiology·John G SledChristopher K Macgowan

❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.