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Week 4 of Pregnancy: All You Need To Know

Baby Development|Body & Life Changes|Your Doctor Visits|Health & Safety
Week 4 of Pregnancy: All You Need To Know

Baby Development

Week 4 of pregnancy baby development is typically the life-changing stage when women learn that they are pregnant. This is an important period of acceptance and adjustment.

How is my baby growing?

The first thing to know about week 4 of pregnancy baby development is the condition of your baby.

During this stage of your pregnancy, your baby is still super-tiny. Your future daughter/son is just the size of a small seed. At this point, the fertilized egg has implanted itself inside your uterus. It will then divide into several layers and some of those will become the embryo. The layers that form the embryo will eventually develop to become different parts of your baby’s body.

The other layers will start to form the placenta. The placenta is the organ that forms to protect your baby during pregnancy. It will then start to connect to the uterine wall. After that, the umbilical cord will grow out of the placenta to connect to your body.

The amniotic fluid, which will serve as a cushion for your baby while inside your body, will start to form during this period. That fluid is starting to form inside the yolk sac.

Body & Life Changes

How is my body changing?

How will your body change during this period of pregnancy? For some expectant mothers, there might be no symptoms yet during week 4 of pregnancy baby development. For others, they might feel cramps or they could see some spots. These symptoms occur when the fertilized egg implants itself into the uterus.

This is the point when the body starts releasing the hormone hCG. This is the hormone that tells the body to stop the ovary from releasing an unfertilized egg each month and stops your monthly menstruation. When you take a home pregnancy test, the hormone hCG will be detected by that test. The body will also increase the production and release of estrogen and progesterone, which are important hormones as well.

What should I be concerned about?

Here are some of the most common pregnancy symptoms that you might experience in week 4 of pregnancy baby development:

  • Morning sickness. This is the most common pregnancy symptom that is experienced by most women, but not all. Morning sickness is one of the first indicators for a lot of women that they are pregnant. Morning sickness causes nausea and vomiting that occurs early in the morning (but may also occur at any time of the day.)
  • Bloated abdomen. The body will start preparing to carry your baby for the next few months, so you can expect your abdomen to start becoming bloated during this period. Your womb will also start to grow in order to accommodate the growing baby.
  • Spotting. As mentioned earlier, you will experience spotting when the fertilized egg moves into the uterus. The bleeding should not last longer than two days. If it does, consult your doctor.
  • Moodiness. This is another common symptom attributed to pregnant women. At week 4 of pregnancy baby development, the body is producing hormones at an increasing level, making a pregnant woman very prone to mood swings. There are several ways that an expectant mother can control those mood swings. These techniques include following a balanced diet, relaxation, and massages.
  • Tenderness of the breasts. The body will also prepare the breasts for nursing the baby, so they will also undergo some changes on week 4 of pregnancy baby development. The number of milk glands will increase, and the layers of fat will thicken. This will result in the breasts becoming larger and tender at the same time.
  • Increased vaginal discharge. Women may notice an increase in vaginal discharge on week 4 of pregnancy baby development. The discharge may be whitish or clear and is sticky. If you notice the discharge to be of a different color or if you notice a peculiar odor, consult your doctor.

These are the main symptoms that you may expect in your week 4 of pregnancy baby development. You may also notice that this week your energy may not be up and you get tired easily. Do not be alarmed because your body is adjusting to the increased hormone levels that may be causing you to feel tired easily. However, consult your physician because this may also be a symptom of iron deficiency.

Your Doctor Visits

What should I tell my doctor?

The moment you suspect that you are pregnant, you should visit your doctor right away. Even if a pregnancy test confirms your pregnancy, the doctor will still request also needs a urine/serum pregnancy test. Your first visit for prenatal care will help determine your due date and help identify risk factors that may impact your pregnancy. Certain laboratory test will be requested and must follow up on the 2nd prenatal visit.

Health & Safety

What should I know about being healthy and safe while pregnant?

Here are a few things that you may want to consider on your fourth week of pregnancy:

  1. Start eating healthy, if you are not doing that yet. You need to include foods that are rich in iron and calcium to help your body prepare for the baby.
  2. Stop smoking and drinking alcoholic beverages. These activities can harm your baby. You should also stay away from second-hand smoke, which is equally harmful.
  3. Continue or start some form of exercise routine. Most pregnant women can do some light exercise. Ask your doctor for what is safe and possible for your pregnancy. Being physically fit will allow you to be better prepared for giving birth.
  4. Start taking prenatal vitamin supplements for you and your baby. Consult your physician regarding these prescribed supplements.

In many ways, week 4 of pregnancy baby development is the official start of your journey as a mother. At this crucial point, you need to take extra care of yourself and your baby in preparation for the months ahead.

Hello Health Group does not offer any advice, diagnosis or medical treatment.

Hello Health Group does not provide medical advice, diagnosis or treatment.

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Written by Tracey Romero Updated Oct 21
Medically reviewed by Jobelle Ann Dela Cruz Bigalbal, M.D.