The second trimester

synonym

2nd trimester, 2nd trimester of pregnancy

definition

Under the term “2. Trimester is the second stage of pregnancy. The 2nd trimester begins at the 13th week of pregnancy and ends at the beginning of the 28th week of pregnancy.

Course of the 2nd trimester

The human pregnancy is medically divided into three roughly equal parts, the so-called thirds of pregnancy (Trimester), structured. Each of these thirds of pregnancy is characterized by a different stage of development in the unborn child. In addition, the expectant mother may experience different symptoms within the different trimesters. While the first trimester begins before the onset of the actual pregnancy on the first day of the last menstrual period, from the 13th week of pregnancy onwards one speaks of the second trimester.

By the beginning of the second trimester of pregnancy, the mother-to-be's body has usually got used to the hormonal changes. At this point in time, the organism is already optimally adjusted to the development of the unborn child. For this reason, it can be observed in most women that the initial pregnancy symptoms decrease significantly or even disappear completely. For this reason, many women agree that the 2nd trimester is the most comfortable third of pregnancy.

On the child's side, the period of rapid growth begins with the 13th week of pregnancy. Both the height and the weight of the unborn child increase significantly each week during this trimester. For this reason, most of the expectant mothers notice significant growth in the baby bump by the 4th to 6th month of pregnancy at the latest. How fast the belly actually grows during pregnancy, however, varies greatly from woman to woman.

Changes and complaints in the second trimester of pregnancy

By the end of the 2nd trimester of pregnancy at the latest, outsiders can see that new life is growing in the womb of the expectant mother. The body of the expectant mother is well adapted to the pregnancy at this point.

With the beginning of the 2nd trimester of pregnancy, the placenta is so mature that it can independently produce the pregnancy-maintaining hormones. The concentration of the pregnancy hormone beta-hCG also decreases significantly within the 2nd trimester. For this reason, it can be observed in most of the expectant mothers that the initial complaints are significantly reduced. In most women, the typical symptoms of early pregnancy disappear completely by the end of the 12th week of pregnancy. Above all, the end of the dreaded morning sickness makes the further pregnancy much easier for the women concerned.

From the 2nd trimester onwards, the unborn child is completely cared for via the placenta. For this reason, the expectant mother can develop other symptoms. Due to the pregnancy-related increase in blood volume, an increased heart rate of around five to ten beats per minute can be seen. For the expectant mother, this accelerated heartbeat at the beginning of the 2nd trimester can be a bit strange and worrying. In fact, these are only subjective complaints that have no disease value.

The increased growth of the mammary glands can cause symptoms in some women even in the 2nd trimester of pregnancy. From around the 16th or 17th week of pregnancy, the mammary glands begin to produce what is known as “foremilk”. Under certain circumstances, this can emerge unintentionally from the chest in the 2nd trimester. Due to the growth of the mammary glands, a slight tugging in the breasts is one of the typical symptoms of the second trimester of pregnancy.

As the child grows, the abdominal organs are increasingly pushed towards the chest. In the course of this, the intestines and stomach in particular are often compressed. Because of this, digestive problems are included to the typical complaints of the 2nd trimester of pregnancy.

Since the weight of the unborn child is increasingly pressing on the bladder, frequent urination is also one of the typical symptoms in the 2nd trimester of pregnancy. Some pregnant women may even leak urine involuntarily when they cough or sneeze. Affected women can often relieve these symptoms by exercising their pelvic floor muscles regularly.

In addition, the development of venous problems and varicose veins is one of the most common complaints in the 2nd trimester of pregnancy. These complaints mainly affect women who frequently stand despite being pregnant. The increasing magnesium requirement can also lead to sensitivity disorders (for example stinging or burning) and muscle cramps in the legs.

Since the unborn child steadily increases in size and weight during the second trimester of pregnancy, the connective tissue and epidermis of the expectant mother can be affected. Many women therefore develop reddish or brownish stretch marks (stretch marks) within the 2nd trimester of pregnancy.

Development of the child in the 2nd trimester

With the beginning of the 2nd trimester of pregnancy, all organs of the unborn child are already in place. However, within this third of the pregnancy they increase in size and continue to mature. In addition, both the gastrointestinal tract and the kidneys begin to work in the 2nd trimester of pregnancy.
While the head in the first phase of pregnancy was disproportionately large in relation to the extremities, chest and abdomen, its proportions adjust over the course of the next few weeks. In addition, in the 2nd trimester the child begins to drink amniotic fluid and pass it off as urine. Since the lungs are not yet fully developed and the alveoli are not yet unfolded, the unborn child continues to be supplied with oxygen via the placenta.

Already at the beginning of the 2nd trimester of pregnancy, the external genital organs begin to differentiate. The sex of the child from the 14th week of pregnancy can be determined with particularly high-resolution ultrasound devices. Most gynecologists wait until the 16th or 18th week of pregnancy until the gender is announced.

The child's bones are also compacted and hardened by the storage of calcium. In addition, the sense organs begin to work. The unborn child can hear the mother's heartbeat within the first few weeks of the 2nd trimester.

From around the 18th week of pregnancy, external noises (e.g. the mother's voice) can also be heard. It can also be assumed that the unborn child can tell the difference between light and dark in the 2nd trimester of pregnancy. At the end of the 2nd trimester of pregnancy, the child's hair begins to grow.

Screening in the second trimester of pregnancy

Screening in the 2nd trimester of pregnancy usually includes a detailed diagnosis of the growth and fetal organs. Screening should usually be done in the 2nd trimester between the 19th and 22nd week of pregnancy.
However, if there are any abnormalities in the ultrasound, a detailed organ examination should be considered.

During the screening in the 2nd trimester of pregnancy, the growth of the unborn child is checked. In this control, the length of the child from head to toe (so-called crown-sole length; SSL), the head circumference and the chest diameter play a decisive role. In addition, screening in the 2nd trimester of pregnancy should assess both the amount of amniotic fluid and the location and structure of the placenta.The gynecologist uses the ultrasound device to visualize the child's development.

Any abnormalities in the amount of amniotic fluid may indicate malformations in the gastrointestinal tract. Assessing the location of the placenta is important, among other things, in order to rule out possible complications during childbirth. Above all, a placenta that is in the area of ​​the internal cervix could make spontaneous birth problematic.

In addition, screening in the 2nd trimester of pregnancy includes an ultrasound scan of the child's organs and heart. This examination primarily checks whether the four chambers of the heart can be visualized and whether there are abnormalities in the area of ​​the inner cerebral water spaces (Ventricle) gives.

Furthermore, during the screening in the second trimester of pregnancy, the gynecologist checks whether the stomach is in the upper abdomen of the unborn child. The supply of the child via placenta and umbilical cord should also be checked during the second trimester screening. For this purpose, a so-called Doppler sonographic examination of the placenta and umbilical cord is carried out. In addition, measuring the blood flow in the maternal vessels (especially the uterine arteries) can be useful.

Read more on the topic: Ultrasound in pregnancy

Screening in the 2nd trimester of pregnancy cannot be done by every gynecologist. A particularly high-resolution ultrasound device is a prerequisite for carrying out detailed diagnostics on the child's organs. If there are abnormalities during this screening, the mother-to-be should be referred to a specialist for further clarification.

Summary

The 2nd trimester of pregnancy begins at the 13th and ends at the 28th week of pregnancy. This phase of pregnancy is characterized primarily by the rapid growth phase of the unborn child. In addition, in most women in the 2nd trimester, the existing pregnancy becomes clearly visible to outsiders.

Since the mother-to-be's body has usually adjusted to the needs of the growing child by the beginning of the 13th week of pregnancy, the typical symptoms of early pregnancy usually subside significantly in the 2nd trimester. In many women, the symptoms disappear completely by the beginning of the second trimester of pregnancy. Above all, the dreaded nausea and regular vomiting are often a thing of the past with the beginning of the 2nd trimester of pregnancy. The mood swings that are typical of the first trimester of pregnancy also mostly flatten out in this part of the pregnancy.

For this reason, most of the expectant mothers find the 2nd trimester of pregnancy to be particularly pleasant. However, the rapid growth of the unborn child can lead to other complaints. Especially towards the end of the 2nd trimester of pregnancy, many women experience severe pain in the lumbar spine. However, the reason for this is not just the increase in size and weight of the unborn child. In addition, the rise in the pregnancy hormone progesterone stimulates the loosening of ligaments and muscles. For this reason, the spine of the expectant mother is less able to withstand the increasing child weight.