3 Weeks Pregnant

Your baby's life begins

3 weeks pregnant:

What's happening with you:

This is it, the week you've been waiting for. Your egg was fertilized at the start of the week, and your body has just begun its amazing transformation. As far as your doctor is concerned, you're well into your first month, but these are actually the very first days of your baby's life. In fact, Baby is only a group of cells right now and you're probably unaware of her existence.

On the other hand, some women claim that they can tell they're pregnant right after conception -- call it mother's intuition -- and some may experience very light implantation bleeding when the egg attaches to the uterine tissue. It's too early to detect many external changes, and most women won't notice any physical sensation with conception. But whether or not you notice any signs at 3 weeks pregnant, you can rest assured that fertilization has occurred and every process in your body is now involved in the development of a new life.

What's happening with your baby:

Well, at 3 weeks pregnant your baby doesn't really resemble a baby at all. Instead, it started this week as a small collection of cells (a handful at first, but multiplying rapidly from here on in), known as a zygote. It goes through a few stages over the next few days, eventually becoming a blastocyst as it travels through the fallopian tube to the cavity of the uterus, where it will float freely as it continues to develop. It will implant in the lining of your uterus about a week after fertilization, but it's so tiny that it would be barely visible to the human eye.

When the sperm met the egg at the start of this week, a series of remarkable and life-changing events happened. Once inside the egg, the sperm lost its tail, grew its head and began to exchange genetic information with the egg. This was when the building blocks of a new human being were laid out. If the sperm was carrying a Y chromosome, you'll have a baby boy in nine months; an X-chromosome-bearing sperm will work with your egg to create a baby girl. Whatever the gender, every healthy baby will contain 23 chromosomes from daddy and 23 from mommy to make an entirely unique arrangement of 46 chromosomes.


Things to do this week:

If you have shied away from exercise up until now, consider changing your tune. This is a great week to begin your pregnancy exercise routine, including gentle and effective strengthening activities like prenatal yoga and healthy cardiovascular workouts like brisk walking or mild aerobic exercise. The type and intensity of your workout will depend on your fitness level before pregnancy, and expect to modify your routine as you move -- and grow -- through your pregnancy.

Some of the best exercises require nothing more than a comfortable outfit and the resistance of your own body, but there are a few tools that will be useful at each point of pregnancy and beyond. One of the most popular accessories is the birthing ball, a relatively large and remarkably versatile rubber ball that can support the weight of an adult. This is essentially an exercise ball, a tool that has been used in gyms and physical therapy departments for quite some time. Since it's designed to help strengthen muscles safely, it's the perfect accessory to use for your pregnancy workouts and also during labor to make childbirth easier and more comfortable. If you invest in one now, you'll definitely get good use out of it over the next several months.


Medical musts:

Before you begin your exercise routine, or continue with your particularly high-intensity workout regime, talk to your doctor. A sudden increase in activity can be a problem for you and your baby, especially when your body temperature rises above 102F and your heart rate exceeds 140 beats per minute. If you have been pretty active up until now, you'll need to cut back your level of exercise (intensity and duration) by at least 20%.

You should schedule your first prenatal visit as soon as you find out you're pregnant, but it's still a little early for that. Conception has just occurred and you probably don't even know that you're pregnant, so unless you experience moderate to heavy bleeding (not the light spotting of implantation bleeding) after exercise or for no discernible reason, wait until after your missed period to book your appointment.

Tips for your partner:

This is an exciting time, and emotions are high. Actually, they're likely high then low, loud then soft, clear then cloudy. Yes, this week can be a little hard to bear because of its heavy significance, so try to be honest about your feelings, share the excitement and top it off with a random act of kindness. Bring her flowers one day this week!

It's also completely normal to share the worry, excitement, anticipation and emotional upheaval that mom-to-be is feeling. In fact, it may be comforting for her to hear that you're thinking similar thoughts; admitting that you share her concerns will help to fend off any feelings of isolation she may be experiencing.

This week's FAQs:

  • I have a feeling I'm pregnant. When can I take a test?

    You better hold on for a bit, since a home pregnancy test won't pick up on the pregnancy hormone until at least 10 days after conception. Next week is the earliest that it could work, but keep in mind that you may need to take a few tests over a few weeks before you can get an accurate reading.

    Some women may think they feel a tingle, twinge or other slight impression following conception, but it's really hard to say if there's any physical sensation that accompanies fertilization. However, it's not uncommon to experience some symptoms when the embryo nestles in your uterine lining. It's normal to feel mild cramping and implantation bleeding, but moderate to severe pain and heavy bleeding can signal a problem and you should contact your doctor right away.

  • If I indulge in something unhealthy before I find out I'm pregnant, will it hurt my baby?

    It can be unsettling to discover you're pregnant after you let loose at a bar, dabble in drugs at a party or have a few late-night cigarettes. It's even more frightening when you've continued a long-time habit right up until that little line showed up on the testing stick. The good news is there's no solid evidence that any drugs or alcohol taken before pregnancy will cause any harm to the fetus. Even a few puffs here and a few sips there in the earliest days of pregnancy were probably harmless. The real danger is in what happens from here on out.

    Drugs and pregnancy don't mix, and that goes for everything from allergy medicine to illegal narcotics. A single dose of a drug before you knew you were pregnant likely won't cause any problems, but the risks grow exponentially as your pregnancy progresses. Once the placenta is formed and organ development increases, even a single use of a drug can cause certain problems for your baby.

  • What vitamins should I take now to help my baby develop properly?

    The first and foremost supplement to get into your daily routine is folic acid, and it's a good idea to start taking it before you even get pregnant. This very important vitamin has been proven to reduce the incidence of neural tube defects like spina bifida by up to 50%. A pregnant woman will excrete up to five times the normal amount of folic acid, so every woman should begin taking a supplement as soon as possible. Most prenatal vitamins contain an adequate amount of folic acid along with other important vitamins and minerals, so work with your doctor to find one that suits you well.

Helpful Hint:

Pregnancy can be scary, but there are plenty of things to look forward to. Your allergies or asthma can become less severe and your risk for breast cancer may decrease. You can say goodbye to menstrual cramps for the next nine months, and migraine headaches will disappear for most women as they move through their second and third trimesters. More good news: women who develop and continue a healthy pregnancy exercise routine for the course of their pregnancy can sidestep many of the common discomforts that come with pregnancy, so you could very well have a surprisingly pleasant nine months ahead of you!

Pregnancy Timeline

First trimester fitness and yoga videos - Prenatal Yoga

First trimester cooking and nutrition videos - Healthy Snacks for Pregnancy

First trimester lifestyle videos - Morning Sickness Relief