The nonstress test (NST) measures how babies’ hearts respond to movement. (Just like yours, your babies’ heart rates should speed up when they wiggle.) While women carrying one child are rarely administered this test, moms-to-be of multiples are very likely to undergo an NST, since all multiple pregnancies are considered high risk. You’ll take the test during the third trimester (as early as week 28), and depending on how many babies you’re carrying and other clinical factors, you may go back into your doctor’s office to do it a few more times before you deliver. If your OB schedules you for this test, take a potty break first — it can last up to an hour. You’ll be hooked up to devices that will measure the babies’ heart rates, and to monitors that will record the babies’ movements. If any of your babies are sleeping, the OB may use a (totally safe!) buzzerlike instrument to wake ’em up. If one or more of your babies doesn’t respond to movement with an accelerated heart rate, your OB may repeat the test or recommend a biophysical profile to make sure the babies are okay in there.
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