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First Trimester: Symptoms and Screening

About First Trimester Development | Symptoms of Pregnancy | First Trimester Visit | Remaining in Good Health during your Pregnancy | Tests and Screenings

About First Trimester Development

During the first trimester, which spans the first twelve weeks of pregnancy, both mother and child will experience a tremendous amount of change. As the embryo establishes itself in the uterus, the initial ball of cells (blastocyst) quickly grows to a fetus able to move his or her own limbs in a matter of weeks.

Normal development during the first trimester includes:

  • By around six weeks, you can see a heartbeat on ultrasound
  • By eight weeks, the head and major body parts have formed
  • By 10 or 11 weeks, you can see limbs and movement on ultrasound

First Trimester Symptoms

Because of the hormonal and physical changes that occur during this time, women will likely experience more severe symptoms, such as nausea after first waking (morning sickness). Other pregnancy symptoms include:

  • Breast tenderness
  • Feelings of fatigue
  • Lack of menstruation
  • Minor bleeding or spotting around implantation
  • Nausea

First Trimester Visit

Symptoms of pregnancy, such as a missed period, can often cause women to initially seek out a pregnancy test and, if positive, schedule their first trimester office visit. During this visit, your physician will perform an ultrasound to confirm pregnancy, correct placement and presence of heart tone. If it is still too early to see on the ultrasound, your physician can also perform blood tests to confirm pregnancy.

Once a heartbeat has been detected and implantation of the fetus can be seen in the appropriate place, routine prenatal labs are performed to check on the health of both the mother and the developing child. A medical history and physical are also done to determine if there are any risk factors for a complicated pregnancy.

Screenings for the following risk factors are performed to avoid complications:

  • Anemia
  • Infectious risk (HIV or hepatitis)
  • Thyroid levels of the mother

Following the return of results, you and your physician can begin to establish an individualized care plan. Most women will see their physician every two to four weeks during the first trimester, unless significant issues such as severe nausea, vomiting or bleeding occur.

Remaining in Good Health during your Pregnancy

While your doctor will be able to provide you with a care plan that is specific to your pregnancy, there are certain things all women should do and avoid while pregnant to take care of themselves and their developing baby.

Things to do:

  • Continue taking prenatal vitamins
  • Exercise regularly
  • Incorporate lean meats, fruits, veggies and fiber into your diet
  • Focus on staying hydrated
  • Try not to be too concerned about calories

When it comes to exercise, if you already have an exercise routine, you should continue to maintain it during your pregnancy. If you are not currently exercising, start by doing light aerobic exercises, such as stretching and yoga. Strength training, along with any exercise that could cause a fall or an injury to your stomach, should be avoided.

Sexual intercourse is also fine during pregnancy. However, if you have any concerns or experience any pain during intercourse, speak with your physician.

Things to avoid:

  • Alcohol
  • Caffeine (limit intake to about one cup of coffee or tea a day)
  • Cat litter (can carry toxoplasmosis)
  • Prepared food that’s been sitting out, such as deli meats
  • Raw fish or larger fish, such as shark and swordfish
  • Smoking
  • Unpasteurized dairy

First Trimester Screenings and Tests

During the first trimester, a nuchal translucency (NT) scan can be performed. The test, which can be performed from 11 weeks to 13 weeks and six days, uses an ultrasound to measure from the top of your baby’s head to the bottom of the spine as well as the thickness of the neck. These measurements along with the mother’s age, the presence of a nasal bone and a blood test will be used to determine the chance of having a child with Down syndrome.

While ultrasounds are extremely helpful in determining risk, the only way to know for sure if your child has a genetic abnormality is through a blood or amniotic fluid sample. Shortly after 11 weeks, a chorionic villus sampling (CVS) test can utilize a sample of cells from the placenta weeks before amniocentesis testing is available.

Speak with your physician about your level of risk and whether early genetic screening is recommended for your pregnancy.

For More Information

For more information or to schedule an appointment, please call 847.733.5707.