What should be paid attention to when doing a color Doppler ultrasound at 28 weeks of SD2.3?

Patient's question:

At 28 weeks, SD2.3, during the color Doppler ultrasound, the doctor in the ultrasound room said the baby's heartbeat was sometimes fast and sometimes slow. When I asked, he said some are like this and the report indicated good fetal heart activity. What is going on? Whom should I trust?

Doctor's answer:

Your situation is normal, there's no need to worry. The precautions for pregnant women include:
1. Early pregnancy: Prevent miscarriage caused by trauma, while paying attention to balanced nutrition and the absorption of trace elements;
2. Middle stages of early pregnancy: Pay attention to prenatal nutrition, engage in appropriate exercise to control weight gain during pregnancy, and prevent the recurrence of gestational diabetes;
3. Late pregnancy: Complications during pregnancy may gradually reappear. Pregnant women should monitor their blood pressure, check for edema, protein in urine, and other symptoms.