How your due date is calculated: Your due date is estimated by adding 40 weeks (280 days) to the approximate first day of your last menstrual period. Only 5% of women deliver their babies on their projected due date, so this date should be used as an estimate - it is not an exact calculation.
Changes in Your Body
During the first three months of pregnancy, or the first trimester, your body undergoes many changes. As your body adjusts to the growing baby, you may have nausea, fatigue, backaches, mood swings, and stress. These things are all normal.
Most of these discomforts will go away as your pregnancy progresses. And some women might not feel any discomfort at all! If you have been pregnant before, you might feel differently this time around. Just as each woman is different, so is each pregnancy.
As your body changes, you might need to make changes to your normal, everyday routine. Here are some of the most common changes or symptoms you might experience in the first trimester:
Many women find they're exhausted in the first trimester. Don't worry, this is normal! This is your body's way of telling you that you need more rest. After all, your body is working very hard to develop a whole new life.
Try these tips to ease exhaustion:
* Get at least eight hours of sleep every night, and a nap during the day when possible. * When you are tired, rest or relax. * Start sleeping on your left side. This will relieve pressure on major blood vessels that supply oxygen and nutrients to the fetus. If you have high blood pressure during pregnancy, it is even more important to be on your left side when you are lying down. * If you feel stressed, try to find a way to relax.
Nausea and Vomiting
Usually called "morning sickness," nausea and vomiting are common during early pregnancy. For many women, though, it isn't limited to just the morning. Although it can seem like it will last forever, nausea and vomiting usually go away after the first trimester.
Try these tips to help prevent and soothe nausea:
* Eat frequent, small meals (6 to 8 small meals a day) rather than 3 large meals. Avoid fatty, fried, or spicy foods. * Try eating starchy snacks, like toast, saltines, cheerios, or other dry cereals when you feel nauseated. Keep some by your bed and eat something before you get out of bed in the morning. If you feel nauseous in the middle of the night, reach for these starchy foods. It's also a good idea to keep these snacks with you at all times, in case of nausea. * Try drinking carbonated drinks like ginger ale or seltzer water in between meals. * Ask your doctor if you should change prenatal vitamins if it seems to be making your nausea worse. Sometimes taking your prenatal vitamin at a different time (e.g. at night not in the morning) can also help. * Ask your doctor about taking vitamin B6 for nausea and vomiting that doesn't get better with dietary changes.
If you think you might be vomiting excessively, call your doctor. Constant nausea and/or frequent vomiting may mean you have a condition called hyperemesis gravidarum. If you lose too much fluid you might become dehydrated. Dehydration can be dangerous for you and your baby.
Frequency of Urination
Running to the bathroom all the time? Early in pregnancy, the growing uterus presses on your bladder. This causes frequent urination.
See your doctor right away if you notice pain, burning, pus or blood in your urine. You might have a urinary tract infection that needs treatment.
During the first trimester, it is normal to gain only a small amount of weight, about one pound per month.
Changes in Your Baby
Three Weeks Pregnant to Four Weeks Pregnant: At 3.5 weeks the fetus: * will have formed the heart * begins development of the brain and spinal cord * starts forming the gastrointestinal tract
Seven Weeks Pregnant to Eight Weeks Pregnant: At 7.5 weeks: * the eyes move forward on the face and eyelids begin to form * the palate is nearing completion and the tongue begins to form * gastrointestinal tract separates from the genitourinary tract * all essential organs have begun to form
Eight Weeks Pregnant to Nine Weeks Pregnant: At 8.5 weeks: * the embryo now resembles a human * facial features continue to develop * beginnings of external genitalia form * anal passage opens, but the rectal membrane is intact * circulation through the umbilical cord is well developed * long bones begin to form
Ten Weeks Pregnant: A fetus at 10 weeks of development has fully formed eyelids and well-formed digits and ears.
Twelve Weeks Pregnant: A fetus at 12 weeks can make a fist and suck its thumb.
By the end of the first trimester, your baby is about three inches long and weighs about half an ounce. The eyes move closer together into their positions, and the ears also are in position. The liver is making bile, and the kidneys are secreting urine into the bladder. Even though you can't feel your baby move yet, your baby will move inside you in response to pushing on your abdomen.
During the early months of pregnancy, regular doctor visits (prenatal care) are especially important. Become a partner with your doctor to manage your care. Keep all of your appointments — every one is important!
During the first prenatal visit, you can expect your doctor or nurse to do the following:
* ask about your health history including diseases, operations, or prior pregnancies * ask about your family's health history * do a complete physical exam * do a pelvic exam with a Pap test * order lab tests * check your blood pressure, urine, and weight * figure out your expected due date * answer your questions
1st Trimester Tests and Procedures
For special genetic or medical reasons, you may need other lab tests, like blood or urine tests, cultures for infections, or ultrasound exams in the first trimester. Your doctor will discuss them with you during your visits.
The most common tests recommended in the first trimester include:
Nuchal translucency screening (NTS)
This new type of screening can be done between 11 and 14 weeks of pregnancy. It uses an ultrasound and blood test to calculate the risk of some birth defects. Doctors use the ultrasound exam to check the thickness of the back of the fetus' neck. They also test your blood for levels of a protein called pregnancy-associated plasma protein and a hormone called human chorionic gonadotropin (hCG). Doctors use this information to tell if the fetus has a normal or greater than normal chance of having some birth defects.
In an important recent study, NTS found 87% of cases of Down syndrome when done at 11 weeks of pregnancy. When NTS was followed by another blood test done in the second trimester (maternal serum screening test), 95% of fetuses with Down syndrome were identified.
Like all screening tests, the results are sometimes misleading. In 5% of women who have NTS, results show that their babies have a high risk of having a birth defect when they are actually healthy. This is called a false positive. To find out for sure if the fetus has a birth defect, NTS must be followed by a diagnostic test like chorionic villus sampling or amniocentesis .
NTS is not yet widely used. If you are interested in NTS, talk to your doctor. If she is unable to do the test, she can refer you to someone who can. You should also call your insurance company to find out if they cover the cost of this procedure. NTS allows women to find out early if there are potential health problems with the fetus. This may help them decide whether to have follow-up tests.
Chorionic villus sampling (CVS)
CVS is performed between 10 and 12 weeks of pregnancy. In CVS, the doctor inserts a needle through the abdomen or inserts a catheter through the cervix to reach the placenta. The doctor then takes a sample of cells from the placenta. Experts use this sample to look for problems with the baby's chromosomes. This test cannot find out whether your baby has open neural tube defects. About 1 in 200 women have a miscarriage as a result of this test.
Source: National Women’s Health Information Center, U.S. Department of Health and Human Services, www.womenshealth.gov