Your Pregnancy Weeks 1 - 4

Your First Month of Pregnancy



Pregnant Calendar

A full term pregnancy lasts 40 weeks (280 days), broken down into 13-week trimesters, starting from the first day of your last menstrual period. That's right, you haven't even conceived in what physicians consider to be the first two weeks of pregnancy. You might as well get used to this idea now: Your first day of pregnancy is the first day of your last menstrual period. Ovulation usually occurs two weeks after that, and most women conceive during that time. So if thinking of a growing human being inside of you isn't strange enough, you are already two weeks pregnant on the day you conceive!

Home Pregnancy Tests are now able to tell if you are pregnant about 10 days after conception - a week before your next period is even due, or your 24th day of pregnancy.

If you think you may be pregnant you should schedule an appointment with your OBGYN as soon as possible for a blood test and your first prenatal appointment (hint: take a list of questions with you). Plan on seeing your obstetrician about once a month through your first and second trimesters. Good health care is necessary for the development of your baby. You should avoid drugs (even many over the counter medicines!), alcohol, excess sugar, caffeine, and cigarettes - even second hand smoke can affect your unborn child.

Your Baby

By the end of your fourth week your baby is an embryo. This group of embryonic cells is growing at a very rapid pace, each cell dividing daily. By the fourth week of pregnancy your developing baby is about 1mm in length and looks like a tiny tadpole, safely attached to your uterine wall and sending hormones to your body. The placenta is beginning to form and many wonderful and exciting changes are about to take place.

This time next year you will have a 16 week old baby!

Can you believe it? Time flies so fast! Be sure you're keeping track of these memories now by creating your Free Pregnancy & Baby Journal today.

Discover More Fun Facts About Your Baby

Do you know what your baby's birth flower, birth stone, and zodiac sign will be? How about when she starts kindgarten, when he'll be driving, and more!

What is your baby's due date?

Your Body

Pregnant Belly - Week 4

Your "next" period is due around the end of your fourth week of pregnancy. This occurrence, or lack thereof, is many times the first symptom of pregnancy. Some women may experience slight cramping or implantation bleeding when the blastocyst attaches itself to the uterine lining, but most of the changes taking place in your body are barely noticeable in these first few weeks.

Most women don't start to "show" until the fourth or even fifth month. In an emergency situation, this can be dangerous! Alert emergency specialists to your pregnancy status with our pink and blue Pregnancy Wristband that says Mommy 2 Be - FREE when you subscribe to our Week by Week Pregnancy Newsletter.

You should start adding calories to your diet. Depending on how much you weigh when you conceive, you should gain anywhere from 15 - 40 pounds during your pregnancy. To achieve this, a woman of average weight at the time of conception should eat around 2200 calories each day for the first 20 weeks, and then 2500 calories a day after that. Remember, you're supposed to gain weight, but be sure to make your calories count! You should eat healthy foods and get the right kind of exercise. You should also be sure to include folic acid into your daily diet, and ask your physician which prenatal vitamin is best for you.

Photo submitted by 4 weeks pregnant Babies Online Member Brittanie Ferris of Fairfield/Maine/USA - "The doctor had just confirmed I was Pregnant!"


Your Pregnancy Week by Week Newsletter

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Pregnancy Video: Weeks 1-4 (First Month)


Of Special Interest In Your 4th Week

Your pregnancy is determined from the date of last menstral period, not date of conception. Each pregnancy, expectant mother, and unborn child is different. Your pregnancy may not progress the same as the information found here. The information here is based on the average pregnancy. It is not meant to be a replacement for any advice your may recieve from your doctor. If you have any concerns about your pregnancy, we advise you to contact your doctor.
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