1. Oolong tea contains a lot of caffeine, which can easily cause nervous system excitement and reduce sleep quality for pregnant women. Moreover, caffeine can be absorbed by the fetus through blood circulation, which may cause excessive fetal movement and may adversely affect the development of the fetal nervous system.

2. Oolong tea contains tannic acid, which will combine with iron in human blood. During pregnancy, the blood system of pregnant women is under great pressure. At this time, drinking a lot of oolong tea may cause iron deficiency anemia, and may lead to insufficient blood supply to the fetus and lead to congenital anemia. It is best for pregnant women to drink less oolong tea, which can be replaced by warm water and light salt water.

Precautions during pregnancy

1, avoid contact with harmful substances: do not dye your nails or hair during pregnancy. If you need to be exposed to harmful substances at work, you should take a vacation during pregnancy, especially during the first three months of pregnancy, otherwise it will easily lead to deformity or abortion.

2. Avoid ionizing radiation: Pay attention to the computer even if it is shielded.

3, regular life and rest: avoid staying up late and eating barbecue.

4. Those who have a bad pregnancy history should see a doctor in time to eliminate cervical incompetence and avoid abortion in the second trimester.

5, timely check-up, such as 12 gestational age card, 20-24 gestational age for abnormal examination.

6. Due to high-altitude ionizing radiation and poor emergency response ability, some airlines also stipulate that they cannot fly after 28 weeks of pregnancy.

7. Do not drive, because the pregnant woman's abdomen may touch the steering wheel, which may easily endanger the lives of pregnant women and fetuses.