Pregnancy: tests are important to do

Which tests should be done even before pregnancy? What should I know about early and late organ examination? And when should amniocentesis be done? Special examination guide

Pregnancy: tests are important to do
In preparation for pregnancy, it is advisable to carry out prior genetic checks. Spouses can perform these checks, according to their religious affiliation - according to the recommendations of the Federation of Genetic Diseases Specialists in the country. The list of tests is updated from time to time, according to the discovery of new genes. Therefore, it is important for women who plan to become pregnant, but who have undergone genetic testing in a previous pregnancy, to see the innovations that occur in genetic tests before each new pregnancy.

What do you check the genetic tests before pregnancy?

Genetic examination aims to detect pregnancy with genetic diseases. Often talked about difficult, untreated diseases, which could not be detected during routine pregnancy screening exams, but only after birth; These diseases can be detected with a simple blood test.

Any other tests that should be done before pregnancy?

It is very important to check for immunity from diseases that may be dangerous during pregnancy, such as measles or chickenpox. This is in order to receive vaccinations for these diseases before entering pregnancy.

It is also of great importance to carry out routine checks regularly with a gynecologist before pregnancy, including a Pap smear examination (PAP) and early detection of physical factors or psychological conditions that may affect a woman's health during pregnancy.

With regard to the general health status, it is preferable to refer women planning to become pregnant to the family doctor; Alternatively: other general examinations within the framework of a gynecologist’s visit, such as: blood count, hypothyroidism, diabetes test during fasting, vitamin D deficiency, kidney and liver performance status, blood pressure test, diabetes test, cholesterol test and BMI examination . If it turns out that the general living condition is not healthy, check the matter before entering pregnancy and receive comprehensive treatment, because general diseases may worsen during pregnancy and may put the life of the mother and fetus at risk.

What tests should be done during the first trimester of pregnancy?

First, a pregnancy screening test is done by means of a urine test, or by a more reliable examination: a blood test (BHCG). If the test result is positive, a comprehensive examination appointment should be arranged with the attending gynecologist. Around the sixth week of pregnancy, the woman will undergo an ultrasound scan in which the presence, safety and location of the pregnancy will be checked. In most cases, this examination can confirm the presence of a fetal pulse; Thus determining the size and generation of pregnancy permanently. In addition, this examination enables the doctor to know whether the pregnancy is outside or inside the womb.

During this meeting with the gynecologist, the woman is required to perform additional blood tests, including: blood counts, pregnancy of a sexually transmitted disease (for example: syphilis), blood type and detection of antigens, general urine examination, diabetes test during fasting, performance of thyroid glands ( TSH), hepatitis sera, CMV, toxoplasmosis and chickenpox - according to medical evidence only.

What does a nuchal translucency check?

A nuchal translucency examination is examined by an abdominal or vaginal ultrasound. Subcutaneous edema of the fetus is present - a thin fluid layer hidden between the skin and the elastic tissue at the rear. There is a direct relationship between the thickness of the region and the possibility of the fetus developing chromosomal syndromes, among them Down syndrome, and with other diseases such as structural defects, heart malformations, malformations in the large blood vessels and others.

The ultrasound examination is performed between the 11th week and the 13th week of pregnancy - it has no specific value that deducts whether the result is "correct" or "incorrect". During the examination, the value of the measured transparency bar and the fetal size index (CRL) are entered into an equation that calculates the level of severity; The result reflects a statistical prediction of a possible birth of a child with Down syndrome.

Hence, nuchal translucency is a scout examination. That is, it indicates the possibility of an imbalance in the fetus, but the examination cannot confirm or rule out the presence of the defect. The examination itself can reveal up to approximately 70% of cases of Down syndrome.

When is a nuchal translucency test not considered sound?

Nuchal translucency 3 mm or more thick; In this case, it is important to direct the woman to receive genetic counseling, even if the results of amniocentesis and chorionic villus testing are sound, it is still preferable to conduct other tests such as fetal echocardiography.

What do the routine ultrasound exams included in pregnancy tests check?

During pregnancy, some ultrasound exams are followed, so that the first test is carried out between week 6 and week 8 of pregnancy - and aims to check the location of the pregnancy (inside or outside the uterus), check the number of fetuses, fetal pulse and determine the camel generation.

The third examination, which is carried out after the examination of nuchal translucency, is carried out between the 13th week and the 16th week of pregnancy; It is an examination of the organs of the early fetus. This examination carefully examines the organs of the fetus and is carried out early in pregnancy. In these weeks, most fetal systems begin to develop - so early organ screening can reveal more than 90% of existing abnormalities.

Another ultrasound examination done between the 20th and 25th week of pregnancy is the late / extended organs examination. This examination is a ventral examination - and is supposed to reveal anatomical anomalies in the fetus. The Ministry of Health recommends that you perform this examination, which is also included in the basket of health services.In this examination, the fetus size, the amount of amniotic fluid are presented, and some organs of the fetus are scanned (according to a list determined by the Ministry of Health), such as: the spine, upper and lower extremities, the four chambers of the heart, the number of blood vessels in the umbilical cord and others.

If the result of the examination is not correct, a targeted organ examination is performed. An extended organ examination is a test that is performed from the 20th week until the 25th week of pregnancy. The examination is done specifically, during which the doctor examines all parts of the fetus. In addition, this examination is used to measure the rate of fetal growth (weight estimation) and to determine the location of the placenta.

Another ultrasound examination is performed in the third trimester of pregnancy, between week 28 to week 32 of pregnancy, and between week 35 and week 37 of pregnancy. Through this examination, the fetus's weight is estimated, the fetus is measured in size and suitable for the pregnancy generation. In addition, by examining the ultrasound, the position and session of the fetus are examined, the amount of amniotic fluid, the location of the placenta, and blood flow, as needed.

What tests should be done during the second trimester of pregnancy?

In addition to early organ examination, a biochemical examination (triple test) should be performed between the 16th week and the 18th week of pregnancy. This examination is included in the basket of health services and is a simple blood test. In this examination, the severity of the presence of various deformities is checked, and it is therefore determined whether other tests are to be performed. The examination includes a triple test (it includes a fetal albumin test, an HCG test and an estriol test) or a quadruple test (including a triple test and an inhibitory test), as needed and according to risk factors.

Amniocentesis examination Starting from the 16th week of pregnancy, amniocentesis examination can be performed in order to detect chromosomal disorders, in addition to examining basic / extended fetal organs, diabetes tolerance, general urine examination and TSH.

In the 26-25 week of pregnancy, when there is an RH- blood type, an antibiotic detection test is performed again.

What tests should be done during the last trimester of pregnancy?

At this stage of pregnancy, from week 26 onwards, the primary goal of the tests is to follow up the pregnancy and is tantamount to preparing the woman for childbirth. In the 30th to 33th weeks of pregnancy, and in the 36th to 38th weeks of pregnancy, additional ultrasound checks are carried out to monitor fetal development, the amount of water, the location of the placenta and other indicators. Laboratory tests are also performed, such as a vaginal GBS examination, a urine test and an updated blood count to be seen in the delivery room. In cases where the pregnancy lasts for more than a week for the expected pregnancy, a fetal heart monitor test is performed, to ensure the safety of the fetus.

Pregnancy tests. Illustration: Shutterstock

What exactly does amniocentesis check? When should the examination be done?

By examining amniotic fluid, fetal chromosomes are examined. Karyotype examination can diagnose Down syndrome (addition of chromosome 21), in addition to an increase or decrease in other chromosomes. During amniocentesis, additions or partial decreases can also be detected in chromosomes, often rare. In certain cases (as recommended by a geneticist), a more accurate examination of the fetus' chromosomes is performed, so that it examines specific genes.

It is recommended that amniocentesis be performed for women at risk of having a fetus with Down syndrome, according to the results of a screening test and biochemistry. If incorrect results are found in the ultrasound examination, and if there is a risk of developing a genetic disease that can be examined, according to genetic counseling - then in this case, amniocentesis is also recommended.

In addition, if during genetic examinations conducted before pregnancy it is found that one or both spouses carry a certain genetic disease, and also in women age 35 and over - amniocentesis should be performed.

Which tests are important to perform after birth?

Six weeks after birth, a gynecologist must be examined to ensure that the body has recovered and that there is no problem. During this period, a vaginal examination is performed to ensure the safety of the ovaries, uterus, cervix and vagina; In addition, the area around the birth canal is examined.


Dr.. David Segal is a senior physician in high-risk obstetrics at Soroka Medical Center and at the Clalit Health Fund.