At 3 weeks pregnant, it has been three weeks since the first day of your last menstrual period. It's possible that you conceived at the end of last week (when you were ovulating), and you are indeed pregnant. Even though you won't miss your period until next week, there might be a chance that you have a baby growing inside your womb.
If you've conceived, your future baby is now just an embryo that consists of a ball of rapidly multiplying cells. This ball of cells – a blastocyst – is making its way through the fallopian tubes to your uterus, where it will imbed (attaches) itself into the lining of your uterus.
A part of the blastocyst will eventually form the placenta. At 3 weeks pregnant, the developing placenta will start to release a pregnancy hormone called human chorionic gonadotropin (hCG) into your bloodstream, and some hCG gets passed through your urine. (A home pregnancy test will give a positive result if it detects hCG in your urine.)
Human chorionic gonadotropin (hCG) is only produced during pregnancy, and it tells the ovaries that it should not release any more eggs." HCG also triggers the increase production of female hormones, estrogen and progesterone. This prevents your uterus from shedding its lining and keeps your baby's safe for the next nine months.
Fun Fact: After your fertilized egg implants (attaches) itself in your uterus, the level of HCG in your body will quickly increase over the next couple of weeks, doubling the amount every few days.
By the end of 3 weeks pregnant, you might be able to take a home pregnancy test and get a positive result. But keep in mind that your hCG levels may be too low for a home pregnancy test to detect it, so if you get a negative result, try again a few days later.
If you have a bun in your oven at 3 weeks pregnant, your tiny baby is roughly .006 inches long – the same size as the head of a sewing pin.
During pregnancy week 3, amniotic fluid is starting to collect around the blastocyst in a cavity that's going to eventually develop into the amniotic sac (bag of fluid that your baby will swim in for the next nine months).
At 3 weeks pregnant, dramatic changes are taking place inside your womb. Your partner's sperm has fertilized an egg, and conception has taken place. Between five and 12 days after you ovulate, the fertilized embryo will be busy burrowing itself into your uterine wall. During this time, you may start to experience some implantation discomfort.
Mild abdominal cramping is normal at 3 weeks pregnant, and it's a sign of implantation. Your body is adjusting to your new pregnancy hormones, and the new little one growing inside of you. Implantation cramping can be one of the first signs that conception has taken place. Your cramps are typically mild and brief (only lasting one or two days).
Implantation spotting or light bleeding may occur in early pregnancy, and it can come with mild cramping. Implantation bleeding isn't anything to worry about, and it's often caused by the fertilized egg burrowing into your uterine lining. Spotting should be very light, and it may be pinkish or light brown in color. (It is never bright red or heavy like a normal period.)
Helpful Tip: The cramping and bleeding that you experience at 3 weeks pregnant should never be severe. If you have heavy bleeding or severe abdominal pain, this may signal a problem and you'll need to call your doctor right away.
In addition to signs of implantation, there are several early pregnancy symptoms to expect at 3 weeks pregnant. Although you haven't missed your period yet, you may start to feel the effects of pregnancy hormones this week.
Elevated body temperature is a universal symptom at 3 weeks pregnant. If you have been tracking your basal body temperature, and you've noticed that it has stayed high for over 15 days in a row, there's a good chance that you're pregnant.
Fatigue is a very common early pregnancy symptom at 3 weeks pregnant. Soon after conception, you may feel exhausted and tired for no reason. Fatigue will last throughout your first trimester, and it's due to the increased levels of progesterone surging through your pregnant body.
Tender, swollen breasts are another pregnancy symptom that you should expect at 3 weeks pregnant. Your breasts may feel sore and painful to touch, similar to how they feel right before your period, but early pregnancy breasts tend to be 10 times more uncomfortable.
By 3 weeks pregnant, you will probably not be aware of any significant changes. You may be aware that you are ovulating. This might be a good time to put your scale away for a while. Weigh yourself one time for the record. You may find that you are slightly bloated due to ovulation. As your pregnancy continues, you'll find your waistline expanding. Some women enjoy keeping track of the incredible shifts in their size and shape during their pregnancy week by week, whereas others dread the inevitable weight gain. Remember that it is natural and healthy to have weight gain during pregnancy.
Most women will gain between 25 and 35 pounds during their pregnancy, more if they are carrying multiples. Much of this weight is distributed among the placenta, uterus, amniotic fluid, fluid in the tissues and your baby. You will also put on about 7 pounds of maternal fat stores, to help support breastfeeding.
Take this time to appreciate and embrace the remarkable changes that are about to occur in your body, and remember that every pound gained is a pound that is going to help support your baby throughout your pregnancy.
If you are trying to get pregnant, you are probably filled with excitement and anticipation. Unfortunately you won't be able to test for pregnancy for another 10 days or so. Even the most sensitive pregnancy tests usually cannot detect a pregnancy until two or three days before your period is scheduled to arrive.
Many people wonder at pregnancy week 3 what their chances might be for having twins. Twins generally occur when more than one egg is released from your ovary or ovaries. Your eggs can be fertilized by two separate sperm, which would result in fraternal or dizygotic twins. Identical twins develop when one egg is fertilized but later divides into two. When twins are identical, they have the same chromosomal makeup, so they have to be the same gender and have the same physical characteristics.
Different twin combinations are possible when you have triplets and quadruplets. For example, if three or more eggs are fertilized, one fertilized egg can sometimes split into identical twins and another egg may be fertilized separately to result in triplets. The human body is endless with possibilities. The entire process is truly remarkable.
If you have a family history of multiples, you are more likely to conceive multiples than someone who does not. Just because you have a history of twins in the family however does not guarantee that you will have twins. Women who are 'multiparous' meaning they have had more than one baby, are more likely to have twins than first time moms. Multiples are more and more common nowadays in part due to reproductive technology and assisted fertility.
The older you get, the less fertile you become. The most fertile years are between 20 and 24. Once you past age 30, it may be harder for you to become pregnant. Don't fret though. Women in their 30s and 40s can still conceive. It just takes some patience. For couples over age 35, it can take between one to two years before you successfully conceive. Just try to stay positive and don't stress if pregnancy doesn't happen right away.
There are several reasons for declining fertility with age. One of the most common causes is related to ovulation. As women age, they don't ovulate as frequently. They may have menstrual cycles when an egg isn't released. Your egg quality and quantity also decreases once you hit your 30s. There are medical conditions that may also negatively affect your fertility, such as endometriosis.
If you're over 35 years old, and you're desperate to have a baby, you should schedule a preconception appointment at 3 weeks pregnant. This gives you the opportunity to sit down with a healthcare provider and talk about your medical history, lifestyle choices, and current medication. You can discuss any concerns you may have about getting pregnant.
If you are trying to become pregnant, now is the time to give up your glass of wine and avoid drinking alcohol during pregnancy. Consider embarking on new rituals during your pregnancy.
Meditation is a wonderful and easy way to relax and is beneficial for both you and your baby. If you find yourself missing the occasional treat, consider an alternative such as a grapefruit juice spritzer. Decaffeinated teas are also a great option throughout your pregnancy. Don't stress out about any drinks you had prior to realizing you were pregnant. It is unlikely that these will have serious effects on your baby.
It is important however when you make the decision to become pregnant or when you find out that you are pregnant that you adopt healthy practices to ensure the well being of your child. Ask your partner to encourage you during the process, and you might find that he is willing to give up his nightly cocktail as well to show support for you during your pregnancy.
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At 3 weeks pregnant, dramatic changes are taking place inside your womb. Your partner's sperm has fertilized an egg, and conception has taken place. Between five and 12 days after you ovulate, the fertilized embryo will be busy burrowing itself into your uterine wall. During this time, you may start to experience some implantation discomfort. 
By 3 weeks pregnant, you will probably not be aware of any significant changes. You may be aware that you are ovulating. This might be a good time to put your scale away for a while. Weigh yourself one time for the record. You may find that you are slightly bloated due to ovulation. As your pregnancy continues, you'll find your waistline expanding. Some women enjoy keeping track of the incredible shifts in their size and shape during their pregnancy week by week, whereas others dread the inevitable weight gain. Remember that it is natural and healthy to have 
Many people wonder at pregnancy week 3 what their chances might be for having twins. Twins generally occur when more than one egg is released from your ovary or ovaries. Your eggs can be fertilized by two separate sperm, which would result in fraternal or dizygotic twins. Identical twins develop when one egg is fertilized but later divides into two. When twins are identical, they have the same chromosomal makeup, so they have to be the same gender and have the same physical characteristics. 
The older you get, the less fertile you become. The most fertile years are between 20 and 24. Once you past age 30, it may be harder for you to become pregnant. Don't fret though. Women in their 30s and 40s can still conceive. It just takes some patience. For couples over age 35, it can take between one to two years before you successfully conceive. Just try to stay positive and don't stress if pregnancy doesn't happen right away. 
If you are trying to become pregnant, now is the time to give up your glass of wine and 