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4 Weeks Pregnant

Your Pregnancy Week by Week

*Counting from the first day of your last menstrual period

Your Baby at 4 Weeks

Your baby is the size of a poppy seed at 4 weeks pregnant - Pregnancy Week By Week Size: 0.04 inches (1 mm)
Weight: Still too small to weigh

Baby is still very small; still only about the size of a poppyseed. In this, the second week of embryonic development, the hundreds of cells forming your baby-to-be have multiplied and are starting to form layers that will each have their own specialized function. The layers that are forming into the placenta have started to produce the pregnancy hormone, hCG. This hormone is what will be detected by the pregnancy tests that you perform at home and that your doctor performs in the office.

The amniotic sac has formed, as has the yolk sac. The yolk sac will produce red blood cells and also help to provide much-needed nutrients to the baby until the placenta has been fully developed and can take over this function. The amniotic sac is going to be filled with cushioning amniotic fluid that will not just house but also protect your growing little one.

Mom at 4 Weeks Pregnant

Mom at 4 weeks pregnant - Pregnancy Week By Week It is still very early on in your pregnancy to know that you are pregnant; however, some women who are very attuned to their body are able to detect slight changes that are as a direct result of the activity in their uterus.

You may be experiencing hormonal shifts that are leaning you more towards feeling a bit grumpy and quick to temper.

Some pregnancy tests might be able to detect a low level of hCG in your urine; however, in order to get the most accurate and reliable results it is generally better to wait for at least one more week. If you do suspect that you are pregnant then you should verify that any prescription and over-the-counter medications you are taking are going to be safe to take during pregnancy. This is a crucial stage in your baby's development; better to be safe and verify with your medical professional.

Common Symptoms:
More frequent trips to the ladies room might be something taking you by surprise this week! A slight increase in your level of thirst, also, might be the reason for the increase in trips to the ladies room!

Light spotting might be expected and may often be confused as the start of your period; don't assume that you are not pregnant if you are experiencing any spotting, even if the spotting is accompanied by cramping. Your uterus is going through a lot of changes and doing a lot of work to prepare for your growing baby, some cramping can be expected.

A bit of breast tenderness can also be expected as your body is starting to be flooded with an array of hormones and changes related to your pregnancy.

Weight Gain:
There should no increase on the bathroom scale this week; however, you should be sure that you are drinking sufficient water. Many women fail to drink enough water, even when their body needs it most during pregnancy.

Continue on your healthy eating and workout regimen! It can only prove to be beneficial for you and your little one!

Try not to play mind games. It can be hard to just sit and do nothing when the most important change of your life could be right around the corner. For the women who are very in-tune with their bodies, there is the possibility that you will notice yourself being a bit grumpier, or maybe using the bathroom a tiny bit more than the weeks before. No matter what you think you feel, try not to make every twinge, tingle or pain into something baby-related until you have a solid confirmation.

Videos - 4 Weeks Pregnant

Your Pregnancy Week by Week Guide: Select a Week

** Note: Every baby develops at a different rate. The numbers provided are averages based on a "typical" pregnancy. Your baby's size and weight may vary significantly. Your healthcare provider is the best person to interpret information on your baby's size, weight, health and development during your ultrasounds and pregnancy.

Community Comments (93)

Comment from CrystalB88 » Posted Jan. 22, 2020 6:54pm
I've gotten faint but non-squinter BFPs with my healthy pregnancies by 10dpo. 15dpo and very strong BFP with #3 :)

Comment from DenJor28 » Posted Jan. 5, 2018 9:37am
My question is how many weeks are you when the amniotic sac starts to form or is the fertilized egg still traveling through the tubes?

Comment from kben1202 » Posted Oct. 10, 2017 1:14pm
19dpo today got BFP at 11dpo

Comment from Joshua2018* » Posted Aug. 31, 2017 8:49pm
16 dpo, got Strong bfp finally after 4yrs of trying and 2 miscarriages, baby #1

Comment from Metal_Yuri » Posted Aug. 31, 2017 11:44am
14 dpo got my positive however got faints from wondfo and clinical guard feom 8 dpo!

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