Editing D-dimer (section)

===Reference ranges===
The following are [[reference range]]s for D-dimer:<ref>[http://www.perinatology.com/Reference/Reference%20Ranges/D-Dimer.htm Reference Values During Pregnancy] at perinatology.com. Retrieved October 2014.</ref>
{|class="wikitable"
! Units !! Nonpregnant <br />adult !! First [[Pregnancy|trimester]] !! Second trimester !! Third trimester
|-
| mg/L or μg/mL || < 0.5 || 0.05 - 0.95 || 0.32 - 1.29 || 0.13 -1.7
|-
| μg/L or ng/mL || < 500|| 50 - 950 || 320 - 1290 || 130 - 1700
|-
| nmol/L || < 2.7 || 0.3 - 5.2 || 1.8 - 7.1 || 0.7 - 9.3
|}

D-dimer increases with age. It has therefore been suggested to use a cutoff equal to patient’s age in years × 10 μg/L (or x 0.056 nmol/L) for patients aged over 50 years for the suspicion of venous thromboembolism (VTE), as it decreases the [[false positive]] rate without substantially increasing the [[false negative]] rate.<ref>{{cite journal | vauthors = Urban K, Kirley K, Stevermer JJ | title = PURLs: It's time to use an age-based approach to D-dimer | journal = The Journal of Family Practice | volume = 63 | issue = 3 | pages = 155–8 | date = March 2014 | pmid = 24701602 | pmc = 4042909 }}</ref><ref>{{cite journal | vauthors = Raja AS, Greenberg JO, Qaseem A, Denberg TD, Fitterman N, Schuur JD | title = Evaluation of Patients With Suspected Acute Pulmonary Embolism: Best Practice Advice From the Clinical Guidelines Committee of the American College of Physicians | journal = Annals of Internal Medicine | volume = 163 | issue = 9 | pages = 701–11 | date = November 2015 | pmid = 26414967 | doi = 10.7326/M14-1772 | doi-access = free }}</ref>

{{Anchor|FEU}}An alternative measurement of D-dimer is in fibrinogen equivalent units (FEU). The molecular weight of the fibrinogen molecule is about twice the size of the D-dimer molecule, and therefore 1.0 mcg/mL FEU is equivalent to 0.5 mcg/mL of d-dimer.<ref>{{cite web|url=http://education.questdiagnostics.com/faq/FAQ149|title=Clinical Education Center|website=Quest Diagnostics}} Document FAQS.149 Version: 3 effective 07/23/2019 to present</ref>