The timing window is narrow, so call 8872524007 once your NT scan is booked.
What the Double Marker test checks
Two pregnancy proteins in the mother's blood:
- Free beta hCG, a hormone made by the placenta.
- PAPP-A (pregnancy-associated plasma protein A), also from the placenta.
On their own these numbers mean little. Screening software converts them into "multiples of the median" for your exact week of pregnancy, then combines them with your age, weight and NT measurement to calculate a risk. This combination is often called first-trimester combined screening.
Why your doctor may order it
Many obstetricians in India offer it to every pregnant woman, because chromosomal conditions can occur at any maternal age, although the chance rises with age. It may be suggested more strongly if there's a previous affected pregnancy or a family history. Taking the test is your choice, and your doctor or a genetic counsellor can explain what it involves.
Alpha Laboratory does not perform or disclose sex determination, which is illegal in India under the PCPNDT Act.
How to prepare
The sample must be taken between 11 weeks and 13 weeks 6 days of pregnancy, ideally on or close to the day of the NT scan. No fasting is needed.
Bring these, because the risk can't be calculated without them:
- The NT scan report, with crown-rump length (CRL), NT value and scan date.
- Your date of birth and current weight.
- Whether the pregnancy is IVF (and if a donor egg was used), twins, and whether you have diabetes or smoke.
Sample type and report time
One serum sample. It's collected at Alpha Laboratory and processed in-house or at a partner reference laboratory, depending on the test. The report is usually ready in 1–3 working days, and we'll tell you the expected date when you book. If you're looking for a double marker test near me around Banur, home sample collection is possible, but please have the scan report ready for the collector.
Understanding your results
The report shows a risk such as 1 in 1,500 or 1 in 150, compared with a cut-off set by the screening programme (many labs use around 1 in 250). Below the cut-off is "screen negative" or low chance; above it is "screen positive" or higher chance.
Screen positive doesn't mean the baby has the condition. Most screen-positive pregnancies turn out unaffected. Your doctor or genetic counsellor may discuss options such as cell-free DNA screening (NIPT), or a diagnostic test like CVS or amniocentesis. A screen-negative result lowers the chance but can't exclude every condition.
FAQ
Is the double marker test safe for the baby?
Yes. It's a routine blood sample from the mother's arm.
What if I'm already 14 weeks?
The double marker window has passed. Your doctor may suggest second-trimester screening instead.
Can I do the blood test before the NT scan?
Yes, if you're at least 11 weeks, but the risk can only be worked out once the scan details are in.
Why do you need my weight?
Marker levels are diluted in a larger blood volume, so the software corrects for weight.
Book at Alpha Laboratory
Book your double marker test on 8872524007, or WhatsApp us a photo of your NT scan report so we can check the dates. See the contact page for directions. Call or WhatsApp for the current price.