Women's Healthcare Topics

3 Weeks Pregnant

Reviewed by James Brann, M.D.
Learn about your symptoms and changes during the 3rd week of pregnancy.

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, your baby is growing inside your womb.

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 early in pregnancy, 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.)

In addition to signs of implantation, there are several early pregnancy symptoms to expect. Although you haven't missed your period yet, you may start to feel the effects of pregnancy hormones this week.

Nausea and vomiting -This is a common early pregnancy symptom complaint of pregnancy. You may begin feeling nauseous right away. Some women may experience both nausea and vomiting.

Elevated body temperature is a universal symptom during the early weeks of pregnancy. 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. 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 now. 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.

Urinary frequency - You may begin to urinate more frequently soon after you become pregnant.

Feeling bloated - You will have a sense of bloating that is similar to the feeling you have during menstruation.

Home Pregnancy Tests

Home pregnancy tests are more accurate the longer you wait. They test a hormone called human chorionic gonadotropin (hCG). This hormone begins to enter the mother’s system about five to seven days after the egg is fertilized. If your last period was only three weeks ago, your body may be just beginning to secrete hCG, which can make it hard to get an accurate pregnancy test. The amount of hCG you secrete in your urine will double every 29–53 hours for the first 30 days after implantation. Waiting just a few extra days before taking a home pregnancy test can improve your chances of getting an accurate result.

Which Brand Offers the Most Accurate Home Pregnancy Test?

If you take a home pregnancy test at just three weeks after your last period, many pregnancy tests may give a negative result even though you may be pregnant. Most women may only secrete about 12.5 mIU/mL of hCG in their urine at this point in the pregnancy, and the vast majority of home pregnancy tests can’t reliably detect such a small amount of hCG (most require up to 100 mIU/mL).

In a clinical study examining 18 different tests, only First Response: Early Results home pregnancy test reliably detected pregnancies with 12.5 mIU/mL of hCG. Other sensitive (but less accurate) test brands included Clear Blue Easy: One Minute and Clear Plan Easy. Many other brands become very reliable once you are just a few days further along in your pregnancy—with each passing day, your home pregnancy test results will be more reliable. By waiting as long as you can, you can save yourself both frustration and money.

Mom's Pregnancy Changes and Symptoms

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, 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.

Most women notice they have to pee more urgently and frequently now. The constantly need to urinate is a classic early pregnancy symptom that almost all pregnant women will experience to some degree. It may feel like your bladder has shrunk, and you may be running to the bathroom every ten minutes.

You may now have nausea and even vomiting which is a typical early pregnancy symptom. Roughly 75% of pregnant women will experience some form of vomiting or nausea in their first trimester of pregnancy.

Baby Section

Growth and Development of Baby

At 3 weeks pregnant, your 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 (implantation) itself into the lining of your uterus.

A part of the blastocyst will eventually form the placenta. Now, the developing placenta will start to release a pregnancy hormone called the human chorionic gonadotropin (hCG) into your bloodstream and 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.

By the end of this week, 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.

At three weeks pregnant your tiny baby is roughly .006 inches long – the same size as the head of a sewing pin. The amniotic fluid is starting to collect around your baby and the amniotic sac (bag of fluid that your baby will swim in for the next nine months) is developing.

Pregnancy Health Section

Your Diet and Nutrition in Pregnancy

What is a healthy diet in pregnancy, we have the answers.

Your diet and nutrition in pregnancy are vital elements of a healthy pregnancy. The healthier you eat, the healthier your body is and the higher the likelihood that you’ll give birth to a healthy baby in 40 weeks.

Eating a balanced diet during pregnancy will ensure that your baby has the best environment to grow in for nine months, and it also decreases the likelihood of nutritional deficiencies that can complicate your pregnancy.

When you’re pregnant, you will want to follow the USDA’s MyPlate (which replaced the Food Guide Pyramid in 2011). MyPlate icon is divided into five food groups:

* Grains – Foods within the grains group are made with wheat, rice, oats, barley, cornmeal, or another cereal grain. Examples of grain products include breakfast cereals, bread, pasta, oatmeal, grits, and tortillas. For a balanced diet, make sure that you eat whole grains (when you can).

* Vegetables – Eat plenty of different vegetables or 100 percent vegetable juice for a healthy diet. Vegetables are organized into five subgroups: dark green vegetables (which are plentiful in folic acid, so make sure you get them into your diet); red and orange vegetables; beans and peas; starchy vegetables; and other vegetables. Half of your plate at each meal should be fruits and vegetables.

* Fruits – Along with vegetables, you will want to eat a wide assortment of fresh fruit or 100 percent fruit juice. Fruits can be a substitute for a sugary dessert, and they can be eaten fresh, canned, frozen, and dried.

* Dairy – Calcium is a vital nutrient in pregnancy, so make sure that you eat dairy products into your everyday diet. You may want to drink one glass of milk with breakfast, or enjoy a milk-based dessert (pudding, ice milk, frozen yogurt, ice cream) for a treat. Cheese and yogurt are also included in the dairy food group.

* Protein – A balanced diet must include protein. You can find protein in both vegetable and meat. Protein can be found in lean meats, poultry, eggs, beans and peas, nuts and seeds, and seafood. Make sure that you choose lean, low-fat sources of protein. Vary the different protein sources that you consume as well.

To have a healthy pregnancy, you’ll want to have adequate nutritional stores. Eating healthy is the way to go.

Nutrients You Need during Pregnancy
In the perfect world, you would meet all of your nutritional needs by eating a healthy and balanced diet. Unfortunately, it’s hard to eat right all of the time. Work and family life can sometimes interfere with your eating plans. To make sure that you get all the nutrients that your body requires for healthy pregnancy, make sure to take a prenatal multivitamin. If you’re a vegetarian, you may need to take an additional vitamin D and vitamin B12 supplement. Your doctor can give you guidance on the right prenatal multivitamin for your needs.

A prenatal multivitamin does not replace a healthy diet. It serves as added protection. You will want to still eat as healthy as you can, whenever it’s feasible.

When you’re pregnant, there are three major nutrients that you will want to pay attention to:

* Folic Acid – Women who are pregnant should get 800 micrograms (0.8 mg) of folic acid into their diet every day. Folic acid is found naturally in certain foods, but you’ll want to ensure you’re getting your daily amount by taking a supplement. Folic acid will decrease your baby’s risk of neural tube defects, such as spina bifida.

Over-the-counter prenatal vitamins typically contain between 600 and 800 micrograms of folic acid. Folic acid (also called folate) can be also found in food, including leafy green vegetables (spinach, broccoli, romaine lettuce, kale, mustard greens), fortified cereals, and beans and peas.

Fortunately, folic acid is water-solvable, so if you get too much folate, your body flushes out the extra that you don’t need.

* Iron – Many women in their reproductive years have low iron stores (not enough iron in their blood). You may not have enough iron due to menstrual bleeding and a poor diet. You’ll want to build up your iron stores, because iron is vital to build healthy red blood cells – which are responsible for carrying oxygen to the cells in your body, and to the womb. Half of all pregnant women don’t have enough iron in her body, and this can lead to premature birth and a low birth weight baby.

Good food sources of iron include lean meats (beef, liver, pork, lamb, and organ meats), poultry (chicken, turkey, duck), fish, and iron-enriched grain products (breads, pasta, rice, and cereals). Your prenatal multivitamin should include iron.

* Calcium – You will want adequate stores of calcium in your body before you try to conceive. Women who are pregnant should aim for 1,000 milligrams of calcium each day. This equals to three or more servings of dairy products each day. You can find calcium in milk products, low-fat yogurt, and cheese.

During pregnancy, if you don’t have enough calcium, your unborn child will draw the calcium from your bones. This can put you at risk for osteoporosis (brittle bones) later in your life.

Although healthy eating can sound like a bore, especially if you’re used to eating junk food and sugary snacks, you should keep your future baby’s health and well-being in mind. You are the sole nutritional source for your baby, so you need the nutritional stores to support a growing baby for 40 weeks!

Conception of a Twin Pregnancy

Learn about twin pregnancy conception.

Though you will not know whether you are carrying twins or a singleton until your first prenatal visit it is fun to think about this idea. At this early week of pregnancy, you may already be carrying twins and not know it!

There are two types of twin pairs: fraternal and identical.

Fraternal Twins
Fraternal twins (also called non-identical twins) occur when two eggs are released during ovulation and they are fertilized. Each twin gets his or her genes from the parents, but the twins will not share the same genetic material. Non-identical twins are no more alike than other siblings, and they can be two different genders. Sometimes, fraternal twins can look very similar and it can be difficult to tell them apart, especially if they are the same gender.

Identical Twins
In the case of identical twins, they develop after a fertilized egg splits into two fetuses. Identical twins are always the same gender, and they share the same genes. This type of twin set is less common than fraternal twins.

Identical twins can share the same placenta, and they can sometimes share the same amniotic sac. Fraternal twins have their own placenta and amniotic sac.

Twin Statistics
Twin births have increased by 70 percent in the last 30 years. This may be due to more women delaying pregnancy until later in life and more women undergoing infertility treatments.

You are more at risk for carrying twins if:

  • You have a family history of twins or multiple births. Heredity plays a role in multiple pregnancies.

  • Women of African descent are more prone to multiple pregnancies than other races.

  • You have had a multiple pregnancy in the past. This increases your risk of having another one

  • You are over 35 years of age.

Twin births occur in one out of every 32 births. Identical twins only occur in one of every 100 births.

Sometimes when you are carrying two babies, you may face extreme bouts of morning sickness (nausea and vomiting). You can sometimes feel more fetal movement than in previous pregnancies. Your belly and uterus will also grow faster or larger than expected.

With a multiple pregnancy, you have an increased risk of certain pregnancy complications, including pre-term labor, high blood pressure, anemia, premature rupture of membranes, and fetal growth problems. You may also need a cesarean section.

When you are pregnant with twins, you will need extra calories and nutrients than a regular pregnant person. You will need to get more calcium and folic acid in your diet. Talk to your doctor about your dietary concerns.

If you have twins in your family, you want to start toying with the idea that you could possibly be carrying twins. Raising twins can be lots of fun!

Vanishing Twin Syndrome
Sometimes a pregnancy can start out with twins, but you have a very early miscarriage. Often occurring in the first trimester, this phenomenon is called "vanishing twin syndrome." The incidence of this strange syndrome is higher than you might think - some estimate that the rate is as high as 30 percent in all multiple pregnancies.

In some cases of vanishing twin, the pregnant woman never knows she was expecting two. Before ultrasound technology, doctors were not aware of this phenomenon.

In other cases, an ultrasound indicates that you're carrying two babies with two heartbeats. You may be overjoyed with this news, but then your hopes are crushed several weeks later, when only heartbeat can be detected.

When vanishing twin occurs in the first trimester, you may not have any symptoms at all. You may experience some cramping or light spotting, but that's it. Without ultrasound, you would have never known!

Often, the miscarried twin had a chromosomal abnormality that caused its death. In most cases, the surviving twin is healthy and will be fine. Research indicates that older moms (over 35) are at higher risk for vanishing twin syndrome.

As you progress through your pregnancy week by week, try not to worry about miscarriage or vanishing twin syndrome. Chances are you will have a healthy baby, if you eat right and abstain from unhealthy habits. (next week)