The Womb At Four Weeks

Before this point in your pregnancy, you may not even know that there’s a bun in the oven. In fact, most women find  out that they’re pregnant during this very week! This can be an exciting time for you, your partner and your family.

Outwardly, however, there may not be any visible signs that you’re pregnant. If you’re carrying on with a busy life as usual, the pregnancy symptoms may not even register on you just yet. When you look back after your pregnancy, however, you will realize that things had changed quite a bit during this week!

Even if you know you’re pregnant, you might not feel you’re pregnant. It may make you wonder about what, exactly, is going on in side of you as well as what you can do to make sure it all goes smoothly. Here’s a run through of everything about your womb at 4 weeks.

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15 Your Little One

At four weeks, your baby will be developing from a blastocyst into an embryo. She may not look the part just yet, though. For one thing, she’s tiny. About the size of a poppy seed or smaller, perhaps.

However, if you could look really closely late in the fourth week, you might see that she’s slowly beginning to differentiate into a little almost tadpole-like shape. That is, you might be able to distinguish what passes for a head, a tail and perhaps even a few limbs. It can be hard to imagine this little thing transforming into a baby. But over the next few weeks, she’s going to change drastically!

14 Implantation

If it hasn’t yet implanted during the third week, your little one is certainly going to do so now. Implantation is basically when the fertilized egg attaches itself to the endometrial lining of your uterus. This connection between you and the little one is important. Over the course of your pregnancy, all your baby’s oxygen and nutrient needs will be coming from you.

Now, this usually occurs at around the time you might have your next menstrual period. Because of this, some women might mistake implantation bleeding for their period. This is especially if you usually have very light flow during your periods.

13 Layers, Layers

Upon implantation, your little one transforms into a blastocyst, a little ball of cells with an inner and outer layer. The inner layer, called the embryoblast, is the part that will transform into your baby, while the outer part or the trophoblast will mostly become the placenta. The cells in these two parts divide continuously and rapidly.

Late into the fourth week, your little one may have developed into three layers: the endoderm, the mesoderm and the ectoderm. The endoderm is the inner layer, which will soon form the cells of the lungs, thyroid and pancreatic cells. The mesoderm, the middle layer, will develop into muscles, kidneys and blood cells. The ectoderm or the outer layer will develop into the skin and nerve cells.

12 Amniotic Sac

During this time, the amniotic sac may also begin to develop. This is, as you may have guessed, the beginnings of the membranes that will hold within it amniotic fluid. Basically, this will be the balloon of water in which your baby will be floating around in, protected from all injury.

At this time, however, there isn’t much in the way of amniotic fluid. The initial sac will be attached snugly onto what will be your baby’s skin. In the future, this will fill up with fluid and expand.

11 Yolk Sac

At this point, the yolk sac attaches to the embryo in order to help nourish it. A bit of a recap: as you may know, the yolk in chicken eggs is the part that provides nourishment to the chicken embryo. The human yolk sac functions in pretty much the same way.

This is important because the embryo’s digestive and circulatory systems are not yet well developed. And since it’s rapidly growing in size, it may not be able to supply nourishment to all its cells for long. The yolk sac temporarily takes over this function until the embryo is capable of doing this on its own.

10 Pregnancy Hormones

At this point, the embryo will begin releasing a hormone called human chorionic gonadotropin or hCG. This hormone is basically a trigger to tell your ovaries to stop ovulation. The ovary listens and instead continuously releases the hormones estrogen and progesterone.

These two hormones are necessary in maintaining the pregnancy. Without them, the endometrial lining might slough off. These two hormones may also result in some of the classic signs and symptoms associated with pregnancy.

9 Early Symptoms

You’re probably not going to have any particularly obvious signs and symptoms yet. However, you might notice that your breasts will become a bit sore. This is the progesterone attempting to get them ready for lactation.

In addition, you might notice that your sense of smell and taste will have changed. This is estrogen, giving a bit of extra protection against anything that could possibly be toxic to your baby. Some women may experience nausea and vomiting, but it’s improbable at this point.

8 A Missed Period

Since your endometrial lining is not sloughing off, you may have noticed that you’ve missed your period. Or, perhaps, you noticed some bleeding, but it’s lighter and lasts for only a day or two. This should make you immediately suspicious that something’s going on down there.

Some moms, however, may not notice just yet. This is especially if her periods tend to be irregular or if there was a history of missed periods not involving pregnancy. In any case, you may or you may not think that you’re pregnant just yet.

7 Positive Test

Since pregnancy tests actually detect the hormone hCG, it is possible that you might have a positive pregnancy test at this point. If your test is negative, however, hCG levels may still not be high enough. In this case, you’ll still want to recheck in about a week or two.

Despite this, however, you might still be holding your breath. As many as 40 percent of pregnancies end up in early miscarriages, some of which you might barely notice. Until your doctor detects a heartbeat at about six weeks, it’s hard to know for sure if this will be the case.

6 Schedule Your Prenatals

Once you have a positive pregnancy test, you might want to schedule your prenatal checkups. In particular, you’ll be looking forward to the one on the sixth or seventh week, when you can hear the fetal heartbeat and the chances of your pregnancy succeeding rises.

It’s extremely important to schedule prenatal checkups and stick to them. In fact, it’s one of the best ways you can significantly decrease your chances for complications during your pregnancy. Your health care provider will be able to detect any potential problems at this point, and then help you take measures to prevent them.

5 Eat Right

Nutrition is extremely important during pregnancy. This is because your growing embryo is going to need specific nutrients to help develop the different parts of her body and get them to function properly. You need to be eating a well-balanced diet.

You will also want to take a folic acid supplement. In fact, if you’ve been trying to get pregnant, you might already have been taking it for a while now. Folic acid is essential in the development of the neural tube. Deficiency in folic acid may result in brain or spinal defects.

4 Good Habits

If you haven’t already, now is an ideal time to stop smoking. Smoking increases your risk of miscarriage, birth defects and premature delivery. If you drink alcohol or caffeine, now is also a good time to cut back. Remember, they may not harm you for now, but your baby is still a tiny thing that is extremely sensitive to these chemicals.

Now is also a great time to start healthy habits. For one thing, you should be getting enough rest so that you aren’t too stressed out during the course of your pregnancy. Regular low-risk exercise such as walking is also a great idea. Exercising helps you build stamina. Specific exercises will also help you develop your pelvic and abdominal muscles in preparation for the big day.

3 Emotional Self-Care

Since this is around the time you will find out that you’re pregnant, you might go through a bit of an emotional roller coaster! Or, perhaps, it may not entirely sink in just yet. In any case, make sure you don’t ignore your emotional needs!

Give yourself time to think about it a little bit. If the pregnancy was planned you will, or course, be thrilled! If it wasn’t, however, you might need some time to process your feelings about it.

2 Breaking the News

This early in the pregnancy, some women opt not to break the news just yet. This is because the certainty of the pregnancy continuing may not be high. You might, of course, still want to tell your partner and maybe your family beforehand. Most women prefer to make the news public after six weeks, after the heartbeat has been established.

If you’re like some women, you might like to break the news to everyone in a fun, creative way. If you want to wait until six weeks before doing so, it might be worth planning ahead to do it.

1 Prepare for Childbirth

Childbirth is still quite far off. However, there are a few things you can do to begin planning for it. The first thing that you’ll want to do is to check your insurance and social security coverage. You want to make sure that you can afford your prenatal checkups and your vitamins.

You also want to be sure that both a normal vaginal delivery and a C-section are covered. Even if you have a low-risk pregnancy and are unlikely to have a C-section, you will want to be secure in knowing you have resources to do so just in case.

Sources: PregnancyCorner.com, WhatToExpect.com, Parents.com, MayoClinic.org, LiveScience.com 

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