What tests should be done in the third month of pregnancy

In the third month of pregnancy (9-12 weeks), the main procedures include NT examination, registration related examinations, early Down syndrome screening, routine prenatal check ups, and special screening. This stage is a critical period for fetal development, and the focus of the examination is to confirm embryo survival, evaluate early fetal structure, and identify the risk of chromosomal abnormalities.

1. NT examination:

NT examination, also known as nuchal translucency scan, is the most important ultrasound screening item during 11-13 weeks and 6 days of pregnancy. By measuring the thickness of the subcutaneous fluid layer at the back of the fetal neck, the risk of fetal chromosomal abnormalities such as Down syndrome can be preliminarily assessed. Thickening of NT values is also associated with fetal structural abnormalities, cardiac abnormalities, and other conditions. During the examination, the fetal position needs to be coordinated. If the position is not good, the pregnant woman may need to recheck after physical activity. This examination requires high technical skills from ultrasound doctors, and it is recommended to conduct it in qualified medical institutions.

2. Filing related examinations:

It is usually necessary to establish a pregnancy file around 12 weeks of pregnancy. At this time, a series of basic examinations will be carried out, including blood routine, urine routine, liver and kidney functions, blood sugar, thyroid function, blood types (ABO and Rh blood types), and infectious disease screening (such as hepatitis B, syphilis, and AIDS). The purpose of these examinations is to comprehensively assess the physical condition of pregnant women, timely find potential problems that may affect pregnancy, such as anemia, thyroid dysfunction or infectious diseases, so as to develop personalized pregnancy management programs.

3. Early Down syndrome screening:

Early Down syndrome screening combines serological testing and NT ultrasound results to calculate the risk probability of fetal chromosomal abnormalities such as trisomy 21 and trisomy 18. Serological testing mainly involves extracting peripheral blood from pregnant women to determine the concentrations of pregnancy related plasma protein A and free human chorionic gonadotropin. The detection rate of early screening is relatively high. If the result is high-risk, doctors will recommend further non-invasive DNA testing or amniocentesis for diagnosis. Please note that the screening results are only for risk assessment and not for diagnosis.

4. Routine prenatal examination items:

Routine prenatal examination at 3 months of pregnancy includes measuring weight, blood pressure, uterine height, abdominal circumference, and listening to fetal heart rate. The doctor will inquire whether the pregnant woman has recently experienced any changes in early pregnancy symptoms such as abdominal pain, vaginal bleeding, nausea and vomiting. Through Doppler fetal imaging, the fetal heartbeat can be clearly heard, confirming the survival of the embryo. At the same time, doctors will assess the nutritional status of pregnant women, guide the supplementation of folic acid or multivitamins, and inform them of the schedule for subsequent prenatal check ups. Monitoring blood pressure and urinary protein can help detect early pregnancy induced hypertension.

5. Special screening:

For pregnant women with high-risk factors, such as advanced age, previous adverse pregnancy and childbirth history, family genetic history, or abnormal conditions in this pregnancy, doctors may recommend more in-depth examinations. For example, chorionic villus sampling can be performed at 11-14 weeks of pregnancy to directly obtain fetal cells for chromosome karyotyping analysis, with a diagnostic accuracy rate close to 100%. But this examination is an invasive procedure with a risk of miscarriage of about 0.5% -1%, and the indications need to be strictly controlled. In addition, if a pregnant woman has a history of recurrent miscarriage, immune related indicators such as antiphospholipid antibodies and blocking antibodies may also need to be tested. The examination at 3 months of pregnancy is crucial for ensuring the safety of both mother and baby. It is recommended that pregnant women complete NT and early screening on time, and complete the registration under the guidance of a doctor. There is no need to fast before the examination (unless liver function and blood sugar are also checked), and wearing split type clothing is convenient for ultrasound examination. If NT thickening or high serological risk is found during the examination, there is no need to be overly anxious, and follow-up diagnostic tests should be carried out according to medical advice. Pay attention to supplementing folic acid in daily life, avoid exposure to harmful substances, maintain emotional stability, and seek medical attention promptly if there are any abnormalities such as abdominal pain or vaginal bleeding.