What does an embryo look like at 4 weeks after conception? Embryo development by day

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

The development of the embryo from conception to birth is a rather difficult period, the well-being of which is determined by the first days of intrauterine life. Each stage of the development of pregnancy is unique in its own way, has its own characteristics and can cause a variety of sensations in the expectant mother. The embryo at the 4th week of pregnancy after conception is quite small, but this period is important in its development.

Different counting methods

There are several ways to determine the gestational age:

• By the date of the last menstruation. When a pregnant woman is registered in the antenatal clinic, gynecologists, as a rule, calculate the term using the obstetric method. This is done as follows: forty weeks are counted from the first day of the last menstruation. This method works quite accurately if the woman has an even menstrual cycle, which is strictly 28 days.
• According to the results of the ultrasound. This method is one of the most accurate, because due to the certain size of the fetus, a specialist can determine the exact datefetus and expected day of delivery. It is worth conducting an ultrasound examination in the first trimester: starting from the 4th obstetric week of pregnancy and ending with the 13th week. It is worth considering that the later this procedure is carried out, the greater the error.
• According to the day of ovulation. If a woman's cycle is twenty-eight days, then ovulation will occur exactly on the fourteenth day. Then add thirty-eight weeks to this day and get the estimated date of birth.
• According to the results of the first stirring. As a rule, during the first pregnancy, the expectant mother can feel the first movements at the twentieth week, and during the second pregnancy - at the eighteenth. Remembering this day, you need to add another twenty weeks (in the second case - 22), so you can calculate the date the baby was born.
• According to the examination of the gynecologist. During the examination, the specialist can accurately determine the gestational age and date of delivery by assessing the size of the uterus of a pregnant woman.

Fetal development

As you know, the development of the embryo at the 4th week of pregnancy is rapid. After the egg is fertilized by the sperm, the zygote divides. Subsequently, this diploid cell passes into the stage of the embryo. The size of an embryo at the 4th week of pregnancy is no more than four millimeters and resembles a small lump of cells, which experts call a morula. By the end of the third week, the heart begins to beat in the embryo, this is easy to determine using ultrasound. At the same time, at the same time,the basis of the skeleton is formed in the child - the notochord, the spinal cord, the brain and its departments.

The embryo develops by the day. So, from the 24th to the 26th day, the foundation of the central nervous system is laid in the baby, and after that, until the 30th day, the visceral arches, the neural tube, and also the limbs are formed.

By the end of the first month, the embryo in the uterine cavity already has muscle tissue, a spine and the beginnings of eyeballs. Further growth of the baby involves the development of existing rudiments.

What does an embryo look like at 4 weeks? At the fourth week of pregnancy, the fetus is not protected by the placenta, which subsequently protects the baby from poor-quality food, medicines and toxins. Therefore, it is important for the expectant mother to monitor nutrition and the use of various medications. It is during this period that hair, future facial features, the brain, respiratory organs, as well as the cardiovascular, nervous and digestive systems begin to form.

Fetal structure: what does an embryo look like at 4 weeks?

This week of pregnancy is all about creating the habitat the embryo needs and producing hormones that support pregnancy.

The size of an embryo at the 4th obstetric week of pregnancy is comparable to a “poppy seed”. The weight of a small grain is about half a gram and the height is not more than four millimeters. But these data change instantly, as the embryo develops by the day due to rapid cell division. Medical professionals often use the concept of the germinal disc, which formsgerm layers. It is a special layer of cells:

• endodermis (inner layer) gives rise to the lungs, pancreas, liver, and also the digestive tract;
• mesoderm (middle layer) is responsible for the formation of the heart and blood vessels, kidneys, muscles, and the skeleton of the child;
• ectoderm (outer layer) is the baby's future nervous system, skin and head (including hair, teeth and eyes).

Extra-embryonic organs

It is worth noting that the embryo in the uterine cavity has everything necessary for full development, including nutrition. The following so-called extra-embryonic organs are responsible for this:

• The yolk sac contains the supply of nutrition for the embryo. It functions throughout the first trimester, after which it resolves on its own. It plays an important role in early pregnancy. Specialists pay great attention to its parameters and condition, as various pathologies or dysfunction of the yolk sac often lead to miscarriage.
• Chorion is one of the components of a normal pregnancy. Its development directly affects the development of the fetus, because without stable functioning, the embryo will simply die. As a rule, this membrane appears one week after fertilization and remains until the placenta is formed. Many experts claim that the chorion subsequently develops into the placenta. In part, this statement can be considered true, since the placenta is formed at the junction of the upper shell of the fetus with the endometrium.
• Amnion representsamniotic fluid-filled sac that contains the fetus. It protects the baby from mechanical damage and drying. Thus, it has the role of protecting the embryo and creating the most natural and favorable aquatic environment.

What an embryo looks like at 4 weeks can be seen in the photo posted in the article.

A certain layer is responsible for the development of individual groups of organs and systems. The embryo has the shape of three discs, which consist of many cells.

Signs of early pregnancy

In the early stages of pregnancy, not every girl suspects her new position. The active development of the zygote affects the female body individually. As a rule, common signs of pregnancy in the 4th week are:

• drowsy;
• mild discomfort in the lower abdomen;
• slight weakness;
• increased urge to urinate;
• malaise.

The above symptoms are similar to premenstrual syndrome, when it can pull the lower abdomen or worsen mood. In addition, the sensitivity of the breast is noticeably increased, since it is typical for the mammary glands to swell almost immediately after conception. And this sign is the most reliable, which confirms the fact of pregnancy. Sometimes women may have a slight rise in temperature, the norm is considered to be no higher than 37 degrees.

At the end of the 4th week of pregnancy, a woman may begin to show the first signs of early toxicosis. It appears inin different ways: severe nausea and aversion to food, or, conversely, changes in preferences. But the fact that toxicosis may be absent throughout pregnancy is not ruled out.

Discharge in the 4th week of pregnancy may be slightly brown, but in small quantities. It is worth noting that slight, odorless discharge, lasting no more than two days, is common in early pregnancy. A specialist should be consulted if a woman has heavy discharge accompanied by pain and other symptoms.

The human embryo at the 4th week develops and changes at a tremendous speed. But in addition to the internal changes of a pregnant woman, there are external ones. For example, at this time, the expectant mother may gain weight, this is due to hormonal changes. But in combination with toxicosis, the figure on the scales may decrease. As long as the woman's overall he alth is good, there is no cause for concern.

Should I do an ultrasound at this time?

Having learned about their situation, every girl wants to look at her baby, but many of them are afraid to carry out this procedure at such an early date. According to experts, such fears are just prejudices. Experts advise screening in the first trimester, starting at the 4th or 4.5 weeks of pregnancy. A study at this time is carried out to determine the viability of the embryo, as well as to exclude various pathologies. What does an embryo look like at 4 weeks? With ultrasonicresearch at this stage of pregnancy, there is a yolk sac, a fetal egg, with a diameter of not more than five millimeters, which is covered with a luminous layer - the chorion.

Usually a 4 week embryo is not visualized, but an experienced specialist will be able to determine its presence or absence, as well as see the contours of the back, abdomen, head and still unformed limbs in the form of gill arches and tail.

Recommendations for expectant mothers

Strange preferences and habit changes in a pregnant woman have long been cultivated in jokes. Indeed, during the bearing of the baby, it is likely that the tastes of the expectant mother may change. As a rule, such a condition begins to manifest itself from the fourth week, as the female body undergoes changes in the hormonal background. In order for the baby to fully develop, and the expectant mother to feel good, it is important to follow a few rules.

Food

For a he althy and full development, it is worth eating foods that contain as many vitamins, amino acids and other useful substances as possible. A balanced diet is important, you need to limit the use of fried, s alty, sweet and starchy foods. The following products are excluded: carbonated drinks, artificial sweets. It is recommended not to take advice such as "eat for two" seriously. Overeating can negatively affect not only the he alth of the woman, but also the embryo. According to experts, the following foods should be included in the diet of a nursing woman:

• Chickeneggs - are high in protein and iron, but they should be consumed boiled and no more than three times a week. It is worth noting that pregnant women should avoid raw eggs.
• Carrots, broccoli, avocados are rich in organic acids, fiber, vitamins and microelements. Carrots contain a large amount of carotene, which is an excellent tool for skin elasticity and is suitable as a prevention of stretch marks on the body of expectant mothers. You can eat vegetables in any form: boiled, raw, baked, in a salad dressed with vegetable oil or sour cream.
• Cottage cheese, yogurts - improve digestion and saturate the intestinal microflora with beneficial bacteria.
• Nuts. It contains nutrients such as magnesium, selenium, vitamin E, which are necessary for the full development of the fetus.
• Fruits and berries - they contain vital vitamins and minerals for the embryo. Small portions of raspberries, strawberries and blackberries are ways to increase the body's defenses. The most important thing is to wash food thoroughly before eating.
• Meat for the unborn child is a source of protein, which is an important building material of body cells, and the liver helps a woman increase the level of hemoglobin in the blood.
• Fish - rich in phosphorus and vitamin D, which helps strengthen the bones and nervous system of a pregnant woman.

Doctor Visit

This gestational age is small enough to be registered with a gynecologist. However, it is in thisperiod of high risk of miscarriage. If a woman notices spotting, a sharp deterioration in well-being, pulling pains in the lower abdomen, you should immediately contact a gynecologist.

Daily routine

At the 4th week of pregnancy, a woman may feel weak, lethargic and sleepy. At this time, it is important to rest as much as possible, to exclude stress. If possible, it is worth arranging a “quiet hour” for yourself every day.

Physical exercise

Probably everyone has heard about the benefits of an active lifestyle while carrying a baby. Therefore, experts strongly recommend doing simple exercises, doing morning exercises and spending as much time as possible in the fresh air. Calm and measured actions have a positive effect on the course of pregnancy. You should dress according to the weather. Clothing and shoes should not be restrictive. It is better to give preference to natural materials in order to exclude allergies and irritations. You need to rest periodically. Remember, excessive loads are undesirable. Only calmness and good mood.

Intimacy

Doctors do not prohibit intimacy in the fourth week of pregnancy if there is no threat of miscarriage, which the gynecologist should warn about. If a woman in the process of intimacy does not experience discomfort and pain, then this will only benefit her.

Medications

Throughout pregnancy, and especially in the first weeks, doctors advise not to self-medicate, so as not toharm the fetus and its mother. Throughout the entire period of bearing a baby, most drugs are prohibited from taking, because they can adversely affect the development of the child. Therefore, even at the slightest hint of a cold, it is better to immediately contact your doctor for qualified help.