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Maternal Screening For Healthy Baby

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Know More About Maternal Screening…From the Expert…

1. Why is Dual Marker not done when one fetus is aborted in case of twin pregnancies?

• If one fetus is aborted, we need to look for the fetal pole. If fetal pole is present in the demised twin, dual test is not possible as there will be production of substances (PAPP-A & Free βhCG) from the demised twin and resulting interpretation will be erroneous. Fetal pole needs 8-9 weeks to close in cases where one fetus in aborted/ fetal reduction If there is no fetal pole we can take the pregnancy as singleton and dual test can be processed.


2. Why do we report single risk in monochorionic twins although the CRL (Crown-rump Length) & NT (Nuchal Translucency) values are different?

• Monochorionic twins originate from the same embryo, so they are assumed to be genetically identical although there is difference in biometry.


3. What is the benefit of NT value measured using FMF (Fetal Medicine Foundation) guideline?

• FMF guidelines provide a standardized methodology for NT measurement. This is paramount in maintaining the sensitivity of the combined screening as it contributes significantly (about 70% to the 91%) detection rate in dual test.


4. What is Corrected MoMs?

• Corrected MoMs are MoMs with weight corrections
» Weight correction should be applied to all analytes in Down’s syndrome screening
» Evidence shows that weight correction improves detection rate
» Multiple median values can be significantly affected by weight correction


5. What is the importance of the sample collected on DBS card over serum?

• Free βhCG is more stable and intact on DBS card. Also dissociation from free βhCG occurs slow onDBS card.


6. Why is maternal screening not done between 14 th & 15 th week of gestation?

• One of the most discriminating marker for NTD is AFP which is best accessed from 15 th week for quadruple test. Hence, the window 14 to 15 week is not ideal for dual or quadruple test.


7. Why we do not report patau syndrome (T13) in 2 trimester screening?

• Sensitivity of patau syndrome is very low in 2 trimester as pregnancies diagnosed with T13 end in miscarriages between 12 to 15 week of gestation ( it is published in AJMG for the incidence to term for T18 and T13)


8. What is the difference between Lifecycle software, ssdw, Astria and Prisca?

• LifeCycle TM risk calculation engine is a comprehensive informatics package for maternal health monitoring and risk assessment. An accessible patient data management system is coupled with a flexible risk calculation engine, which can be configured to meet local variations. Because the system has been fully validated and all calculation methods, algorithms and values are supported by current published literature, LifeCycle gives full confidence in maternal risk assessment program.


9. Insights of Pre-eclampsia (PIGF- PLACENTAL GROWTH FACTOR)

• Pre-eclampsia is a sudden increase in blood pressure and protein in the urine after the 20th week of pregnancy. Pre-eclampsia can lead to eclampsia, or convulsions, posing serious health implications for mother and baby. Symptoms of pre-eclampsia may include:

» High blood pressure (≥140/90 mmHg)

» Swelling in the face and hands (and feet, although swollen feet are common during pregnancy)

» Weight gain of more than 2 kgs in a week

» Other problems such as headache, blurred vision, abdominal pain and nausea


10. What is MAP & uAD and what is the relevance in PlGF test?

• Mean Arterial Pressure (MAP) – Accurate measurement of blood pressure in pregnant women is particularly important when attempting to identify early signs of pre-eclampsia. As a means of prediction it has been suggested that the MAP, whether measured in the first or second trimester, is better than systolic blood pressure, diastolic blood pressure, or an increase of blood pressure. In clinical practice MAP measurement in the first trimester may not make a clinical impact in isolation but could be suitable for use with other markers, including maternal serum markers, to improve the accuracy for estimating risk of pre-eclampsia

• Uterine Artery Doppler (uAD) – The uterine artery Doppler can be evaluated by direct visualization, i.e. examining the characteristics of the waveform to determine if nothing is present or absent, or by quantifying the waveform by measuring the blood flow velocity at peak systole (maximal contraction of the heart) and peak diastole (maximal relaxation of the heart). These values are then computed to derive a ratio. The most common approach is to measure the Resistance Index (RI) in which the peak of systole is divided by the sum of systole and diastole

• RI= systole/ (systole + diastole)

• In early pregnancy the peak flow at diastole is less than later in pregnancy. Therefore, as the duration of pregnancy increases, the amount of blood flowing in the umbilical artery increases during diastole


Maternal Screening Solutions in association with PerkinElmer

Code Test Name Sample Comment/ Description


Dual Marker Test:

(11 – 13.6 weeks) PAPP-A, Free ß hCG

2 ml serum / DBS Card

NT by USG report * (NT & CRL values) and brief clinical history required


Triple Marker Test:

(15 – 21.6 weeks) AFP, β hCG , uE3

2 ml serum

USG report * and brief

clinical history required


Quadruple Marker Test:

(15 – 21.6 weeks) AFP, β hCG , uE3, Inhibin – A

2 ml serum

USG report and brief

clinical history required


Integrated Test: Dual Marker (First Trimester Screening) & Quadruple Marker (Second Trimester Screening)

2 ml serum

NT by USG report in 1* trimester & USG report in 2nd trimester and brief clinical history required

Sequential Test: (Combined risk evaluation even if Dual Marker is done seperately)


Dual Marker Test:

(11 – 13.6 weeks) PAPP-A, Free ß hCG

2 ml serum

NT by USG report * and brief clinical history required


Quadruple Marker Test:

(15 – 21.6 weeks) AFP, ß hCG, uE3, Inhibin A

2 ml serum

USG report * and brief

clinical history required, (Patient needs to carry Dual Marker report)


Prenatal BoBs TM

(Aneuploidies + Microdeletion)

3 ml Amniotic Fluid /

Chorionic Villi

Brief clinical history



KaryoLite BoBs TM

Placental biopsy without blood clot in normal special container provided by Lab

Brief clinical history


*Latest Sonography report (USG) performed 1 month prior to blood test is accepted.


Aston, 2 nd Floor, Sundervan Complex, Opp. Union Bank, Above Mercedes Showroom, Andheri West, Mumbai – 400053

Book your appointment to do maternal screening.