Review Question - QID 108970

A 32-year-old G1P0 presents to the antenatal testing unit at 32 weeks of gestation for a non-stress test (NST). Yesterday she had several episodes of diarrhea and vomited once after attending a company picnic 2 days ago. She took loperamide with symptomatic relief. She is worried that she is dehydrated but otherwise feels well and has recovered from her gastrointestinal illness. The patient was diagnosed with gestational diabetes after routine screening in the 2nd trimester and has been started on insulin after unsuccessful attempts at lifestyle management. She also has migraines and gastroesophageal reflux disorder. The patient has a 15-pack-year smoking history but quit smoking in her 1st month of pregnancy. She denies alcohol or drug use. Her temperature is 98.5°F (36.9°C), blood pressure is 122/82 mmHg, pulse is 84/min, and respirations are 14/min. A representative portion of the NST is shown in Figure A. Which of the following is the most likely explanation for this patient’s non-stress test (NST) results?