Pregnancy Calendar at Week 3

What's Happening with the Baby

In the third week of pregnancy, significant changes are happening with the future baby. These changes are entirely dependent on the biological processes in the mother's body and her health condition. The baby doesn't yet have a protective system like the placenta, and its viability is supported by the woman's hormonal background.

As a result of the fusion of two sex gametes (female and male), a single cell is formed. This cell transforms and changes daily.
Every minute, the future baby moves through the fallopian tube towards the reproductive organ. All conditions for its attachment are already prepared here.

The size of the embryo is still so small that it can only be seen under significant magnification. However, in just a few weeks, it will be visible during an ultrasound.
At the beginning of the third week of pregnancy, the baby is just one cell. By the end of this period, it consists of many cells and is called a blastocyst.

Visually, the baby resembles an elongated ball filled with fluid. It doesn't have arms and legs yet, but they will soon form from the cells.
In the third week, the yolk sac provides nutrition for the future baby. In 2-3 weeks, it will be clearly visible on an ultrasound.

The corpus luteum helps sustain the life of the future baby. This gland produces the hormone progesterone, which suppresses the contractile activity of the uterus.
In the middle or end of the third week, the fertilized egg implants into the uterine lining. Here, the baby will develop and grow over the next several months.

Despite the visual absence of organs, the future baby already has genetic data set by the third week. The baby's gender, eye color, skin tone, and other traits are determined.
At the end of three weeks, the production of human chorionic gonadotropin begins. This marker can already inform the future mom about her new condition.

Development of Twins

At three weeks, twins are almost indistinguishable in development from a single pregnancy. During this period, cell formation and division also occur. However, certain processes in the woman's pelvis can differentiate a multiple pregnancy from a single one at this stage.

In a single pregnancy, the embryo travels down the fallopian tube into the uterine cavity and implants there. This process is quite straightforward. In a multiple pregnancy at three weeks, there are several possible scenarios:

If the woman had a single ovulation, one sperm fertilized the egg. During cell division, two embryos formed within one fertilized egg. The cells travel to the uterine cavity and implant in the lining. The future children already have their gender determined. Most often, such twins are of the same sex and look very similar to each other.
If the woman had double ovulation, two sperm cells participated in fertilization. Each sperm cell contributed its genetic material. As a result, two fertilized eggs formed. By the end of the third week, they reach the uterine cavity and implant. These babies can be of the same or different sexes and will have visual differences since they have different genetic sets.

Twins in the later stages of pregnancy often lag behind their peers in growth and weight. But at three weeks, this difference isn't noticeable. Cells divide rapidly, just like in a single pregnancy.

What's Happening with Mom

Significant changes in the body of the expectant mother have already started to occur. However, most women are still unaware of them. If the expectant mother has short intervals between her periods, the first signs of pregnancy may appear as early as 3 weeks. However, for most average women, the menstrual cycle is 4 weeks long.

Uterus and Appendages

The size of the reproductive organ is slightly enlarged. It does not exceed the normal range for the premenstrual period. One of the ovaries has an actively functioning corpus luteum. This structure is responsible for producing progesterone – a hormone essential for maintaining pregnancy.

Breasts

The size of the mammary glands has increased slightly. A woman might already notice that her usual bra feels a bit tight. The nipples are more sensitive. Any touch can cause discomfort. Some women experience itching around the areola in the third week, which can also be taken as a sign of pregnancy.

Body Weight

During pregnancy, gaining body weight is inevitable. However, at 3 weeks, this gain is not due to the growing size of the baby or the volume of amniotic fluid, but rather due to fluid retention. Elevated levels of progesterone cause water molecules to accumulate in the soft tissues. Women may notice slight swelling through their clothes and shoes.

Gastrointestinal Tract

By the 3rd week, the functioning of the intestines changes. Due to increased progesterone, peristalsis slows down, which can lead to bloating and constipation. Hormonal changes in the first month of pregnancy also cause changes in taste preferences. A woman might crave foods she previously had no interest in. At the same time, her favorite foods might start to seem unappealing.

Skin

At 3 weeks, 70% of expectant mothers experience localized breakouts on their faces. The cause is hormonal changes. Similar processes occur in women during the premenstrual period, so most don't pay much attention to them.

Body

At 3 weeks pregnant, you might start noticing a fine layer of hair on your belly and chest. As your pregnancy progresses, it can become more noticeable. Many women try to deal with this issue, but it's better not to. After giving birth, your hormones will balance out, and the hair will disappear on its own.

Reproductive Organs

At three weeks, many women experience a flare-up of chronic urinary and reproductive system conditions. The reason for this is a weakened immune system. At this stage, if you have any complaints, it's better to see a doctor rather than self-medicate. Up to 80% of women report cottage cheese-like discharge and itching in the intimate area. These symptoms indicate a flare-up of vaginal candidiasis.

Pregnancy Challenges

Most often, pregnancy challenges arise in the first month. Every expectant mom can face them, so it's important to know how to act in different situations.

Miscarriage

The most common problem at 3 weeks is a miscarriage. Sometimes it happens even before a woman knows about her new condition. Up to 50% of pregnancies end right after the fertilized egg reaches the uterine cavity. The characteristic signs of a miscarriage are painful sensations accompanied by cramps in the lower abdomen.

Corpus Luteum Insufficiency

About 40% of women who already know or suspect they are pregnant face this problem. With a lack of progesterone, an expectant mom at 3 weeks may experience pulling sensations in the abdomen and heaviness in the lower back. There may be slight bloody discharge. The problem can be resolved if detected in time.

Detachment of the Fertilized Egg

This condition arises due to various reasons: physical or emotional stress, progesterone deficiency, uterine pathologies. With detachment, a woman may not have any characteristic complaints. The problem manifests as bleeding caused by the emptying of a hematoma. The detachment of the fertilized egg can be seen on an ultrasound after 4 weeks.

Ectopic Pregnancy

This condition can be considered a true disaster for a woman. An ectopic pregnancy at 3 weeks shows no symptoms, but within just one week, a woman may experience severe pain, vaginal discharge, and a decline in overall well-being. In this case, there's no time to waste. The sooner treatment is administered, the better the chances of preserving reproductive function. An ectopic pregnancy cannot result in childbirth.

Cervical Pathologies

At the third week, a doctor might suspect pregnancy during a visual examination of the genital organs. The cervix takes on a bluish tint due to increased blood flow in the pelvis. If there are cervical pathologies, symptoms may intensify. Erosion and ectopia manifest as pink discharge. Endocervicitis and endocervical cysts cause heavy discharge. Some cervical pathologies can be contraindications for natural childbirth.

Endocrine Disorders

Thyroid diseases are dangerous for a pregnant woman even at 3 weeks. Since this period involves active cell division and organ formation in the baby, insufficient or excessive thyroid function can impact this process. Women with thyroid pathologies are more likely to give birth to children with intrauterine anomalies. Therefore, it is crucial to rule out potential problems early on, and if endocrine disorders are present, to provide appropriate correction.

What You Can and Can't Do

From the very first days of pregnancy, a woman needs to pay closer attention to herself and reconsider her lifestyle. At 3 weeks, there's no noticeable baby bump yet, but this is precisely when the most crucial phase begins, as the formation and development of the future baby are underway.

What an Expecting Mom CAN Do:

Keep working if your career doesn't involve heavy physical labor. Don't start treating your condition like an illness as early as 3 weeks. If you're feeling good, it's recommended to take medical leave only after 30 weeks, and if you want, even later.
Take folic acid. Multivitamin complexes are usually not prescribed at 3 weeks, but folic acid is very important at this stage. Even if a woman isn't planning to see a gynecologist yet, it's worth starting to take vitamin B9 on her own.
Lift no more than 3 kg (about 6.6 lbs). You don't need to completely give up physical activity. However, carrying heavy loads is already dangerous. That's why doctors usually allow lifting between 2 to 3 kg (about 4.4 to 6.6 lbs) at a time.
Have fun if you're feeling good. Don't deny yourself travel, hiking, or long and exciting walks. You can meet up with friends and go to cafes.
Maintain an intimate life. Pregnancy isn't a reason to give up sexual activity. In the absence of problems, it can even be beneficial, as it enhances blood circulation in the pelvic area and triggers a surge of the happiness hormone.

What an expectant mother should avoid:

Drinking alcohol, smoking, and using drugs. It's important to cut out all bad habits from your life as early as 3 weeks into pregnancy.
Taking medication on your own. Even over-the-counter pain relievers and fever reducers can be dangerous for the baby.
Experiencing stress. Nervous tension increases cortisol and adrenaline levels. These hormones are not beneficial for the future baby.
Overexerting yourself physically. Lifting heavy objects, intense sports activities, and sudden movements can lead to increased uterine tone.

Proper Nutrition

Throughout the entire pregnancy, the expectant mother needs to receive proper nutrition. Most micronutrients come from the food a woman eats. They ensure the correct formation of the baby's systems and organs and help prevent pregnancy complications.

In the 3rd week, it is recommended to:

Consume plenty of dairy products. The active formation of the musculoskeletal system will soon begin, and the baby needs calcium for this. Cheese, cottage cheese, kefir, sour cream, and fermented baked milk are rich in calcium. Additionally, dairy products help restore gut flora, which is a good way to prevent constipation.
Eat meat or fish daily. Animal products contain a large amount of protein, which is essential for the pregnant woman and her future baby. Protein-rich foods help prevent excessive weight gain. For the baby, protein ensures proper cell division.

Include seasonal fruits and vegetables in your diet. They are packed with nutrients and vitamins. Plus, fruits and veggies are a great source of fiber. They help regulate your digestive system and ensure proper digestion.
For breakfast and lunch, go for complex carbs. They don't cause a sugar spike, which is not ideal in the 3rd week of pregnancy. Complex carbs provide energy, help combat fatigue and drowsiness. You can get them from pasta, cereals, and whole grain bread.

You can still enjoy sweets and pastries in the 3rd week. However, it's important to consume them in moderation and not overdo it with sugar. Excessive indulgence can cause an insulin spike and may lead to gestational diabetes.
It's recommended to drink at least 1-1.5 liters of water daily. Water hydrates your cells, makes your skin more elastic, and helps prevent stretch marks. Staying hydrated in the 3rd week also helps prevent constipation and gas.

At three weeks gestation, women typically don't experience significant morning sickness or changes in eating habits yet. So, it's a good time to focus on healthy eating, including more fruits and vegetables, dairy products, and lean meats.

In 1-2 weeks, they'll become repulsive, so you should take advantage of the opportunity now to replenish the nutrients in your body.

Need for Vitamins and Minerals

Taking multivitamin complexes in the early stages should be done based on a doctor's recommendation. At 3 weeks pregnant, most expectant mothers have not yet visited a gynecologist and do not have such a recommendation. Therefore, the main source of vitamins and minerals continues to be food.

Vitamin B9

This nutrient should be a top priority in a pregnant woman's diet. However, diet alone is not enough for the expectant mother. Therefore, it is better to take folic acid additionally. It is needed for the division of cells in the developing baby's body. Vitamin B9 is involved in the formation of the nervous system and brain.

Food sources of folic acid:

green salads;
Brussels sprouts;
live yeast;
pomegranate seeds;
grapefruit pulp;
buckwheat groats.

Vitamins B6 and B12

These ensure the proper functioning of the nervous system for the expectant mother and prevent emotional overload. They are involved in cell division and the production of blood cells. Vitamins B12 and B6 reduce the severity of morning sickness, and their deficiency often causes discomfort at 3 weeks.

You can get these nutrients from:

eggs;
poultry;
seafood;
bananas;
beef;
bell peppers;
legumes.

Vitamin E

It's equally important to maintain adequate levels of Vitamin E during the third week. Tocopherol regulates hormonal balance and ensures the proper functioning of the ovaries and adrenal glands. A deficiency in Vitamin E can lead to increased uterine tone.

You can get additional amounts of tocopherol from:

vegetable oils;
rye bread;
ripe avocados;
sweet bell peppers;
nuts and seeds.

Iron

During the third week, up to 30% of women experience anemia. Iron deficiency manifests as fatigue, apathy, and drowsiness. Taking iron supplements can have the unpleasant side effect of constipation.

Therefore, it's better to get this essential mineral from:

liver;
caviar;
fish;
seafood;
egg yolks;
lentils;
chocolate.

Magnesium

A magnesium deficiency at three weeks can lead to muscle spasms. Contractions of the uterine walls can cause the detachment of the fertilized egg and may result in a miscarriage. Insufficient magnesium intake can also cause headaches in expectant mothers.

Therefore, your diet should include:

wheat germ;
poppy seeds;
raw almonds;
cashew nuts.

Iodine

In the third week, a woman's need for iodine increases. This element is essential for the proper functioning of the thyroid gland. If there's a deficiency, the expectant mother may experience excessive sweating, shortness of breath, and fluctuations in blood pressure.

Sources of iodine include:
seaweed;
salmon;
shrimp and crayfish;
oysters and mussels;
egg yolks.

Important! Choose a multivitamin complex based on your doctor's recommendation.

Helpful Tips

If you find out about the pregnancy at three weeks, it's time to rethink your lifestyle. It's crucial to immediately give up any bad habits if you haven't already. From now on, all food, drinks, medications, and even emotions are passed from the mother to the baby. A woman is responsible for her baby from the very first days after conception. The main rule for the next nine months is to lead a healthy lifestyle.

Three weeks is the earliest time when partners can find out about the pregnancy. New experiences, backed by changing hormone levels, make a woman more emotional. The future dad should be patient and resilient in dealing with his partner's mood swings. By the start of the second trimester, the emotional storms will calm down, and her emotional state will stabilize.

Exercises for Expecting Moms

At three weeks, a woman is still living her usual routine and doesn't suspect any changes have occurred. That's why many expectant mothers continue to engage in sports. If the hCG result is already known and indicates conception, then physical activities should be approached with more caution.

To improve blood circulation in the pelvic area, it is recommended to:

take daily walks;
swim;
do gymnastics;
perform exercises to strengthen the back;
practice yoga.

Discomforts During Pregnancy

Nausea. Even at just 3 weeks, women may start experiencing the joys of morning sickness. It begins with nausea and can later lead to vomiting.
Constipation. The lack of bowel movements and gas are triggered by hormonal changes and decreased intestinal motility.
Increased drowsiness. At 3 weeks, women may feel weak, drowsy, and less productive. This is also due to new hormones.
Vaginal discharge. These discomforts arise from a decrease in the body's resistance.
Headaches. These occur due to hormonal changes or as a result of emotional stress.

Checklist

Get a blood test to determine the level of human chorionic gonadotropin with a 1-2 day interval.
Visit a gynecologist to get tests done and obtain a list of documents needed for registration.
Reevaluate your lifestyle, diet, and physical activity.
Purchase a new bra, as your breasts have already become fuller and require special care.
Choose a new skincare line, paying attention to products that prevent stretch marks.
Inform the future dad about the new situation if he hasn't received the good news yet. If desired, notify relatives and close friends.

1. What can I expect to see at a 3-week ultrasound?

2. I am 3 weeks pregnant and constantly hungry. Is this normal?

3. Does an early positive pregnancy test mean twins?

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