What to check at 15 weeks of pregnancy

The 15th week of pregnancy is in the early stage of the second trimester. During this period, certain examinations are needed on the pregnant woman's body and the development of the fetus. Specific examination items include blood hCG test and Down syndrome screening. Through these examinations, it can be confirmed whether the hormones in the pregnant woman's body are normal, and it can also be confirmed whether the fetus is a Down syndrome baby. If there are any abnormalities in these two examinations, women need to take certain measures to regulate their bodies.

1. Key points of prenatal checkup at 15 weeks of pregnancy

You are 15 weeks pregnant. You need to have a prenatal check-up this week. The next check-up will be at 16 weeks of pregnancy. Some projects must be performed in the middle of pregnancy, so pregnant mothers must not miss the time. This week we will learn about one of the items in the mid-pregnancy check-up: the hCG test for Down syndrome.

The second trimester Down syndrome screening is a routine examination for older pregnant women. It checks the concentration of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) in the pregnant mother's blood, and then adds the pregnant mother's age to assess the probability of having a baby with Down syndrome. The similarity between this screening and the first trimester screening is that both assess the probability and risk of having a baby with Down syndrome. The results of the second trimester screening will take about 2 weeks to come. The best time to do this test is between 15 and 20 weeks of pregnancy.

3. Prenatal check-up items that need to be understood during the 15th week of pregnancy

1. hCG (Down's syndrome) method:

(1) Two indicators of testing: Mothers over 35 years old will undergo serum screening, with an accuracy of about 45%. After this test, if amniocentesis is combined, the accuracy rate can reach more than 99%.

(2) Four indicators test: The four indicators are the test of pregnant mother's serum chorionic gonadotropin, estriol, fetal alpha protein and inhibin. According to foreign reports, it can screen out 80% of Down syndrome, 95% of trisomy 18 (abnormal chromosome 18) and 95% of spina bifida.

2. Normal value of hCG (Down's syndrome): On the Down's syndrome screening checklist, the reference range of the median multiple of β-hCG is 0-2.5. If it is higher than this value, it will have an adverse effect on the safety of mother and baby during pregnancy. For example, pregnant women are more likely to suffer from gestational hypertension. This needs to be judged based on the actual individual situation. Some pregnant women have received hCG injections to preserve the fetus in early pregnancy, so there is a possibility that the hCG values ​​will be high during the Down syndrome screening.

3. Tips for prenatal checkup at 15 weeks of pregnancy

1. The blood hCG test is drawn from venous blood. Since the hCG content is not affected by eating, there is no need to fast or hold urine. It is recommended to check in the morning. Currently, the three most commonly used measurement methods in clinical practice are: enzyme-linked immunosorbent assay (ELISA) screening method, sandwich enzyme immunoassay method, and immunocolloidal gold method. These methods have good sensitivity, low cost, and rapid detection, and are widely used in clinical practice.

2. You should have your second prenatal check-up starting from the 16th week of pregnancy! There is still one week left until the second formal prenatal check-up.