The First Trimester Ultrasound

vitaMedMD

First trimester ultrasound

Prenatal care is vital to the health and wellbeing of you and your unborn baby, and often an important part of prenatal care may include an evaluation with ultrasound. Many expectant parents are delighted for the opportunity to see their growing baby, yet the experience can be accompanied by a variety of emotions and questions.

Some questions may include:

Why am I having an ultrasound? When will I have an ultrasound? What will it be like? What will my baby look like?

What to Expect During Your First Trimester Ultrasound

Typically, the first ultrasound will be done anytime within the first trimester of pregnancy.1,2 Most often, ultrasounds during pregnancy will be done externally with a transabdominal wand with gel; however, earlier on in the first trimester, it may be necessary to complete the ultrasound transvaginally.1,2 During a transvaginal ultrasound, a wand covered with a condom and gel, is placed in the vagina to allow for early visualization of the baby.1,2 If a transabdominal ultrasound is done, the bladder typically needs to be full to obtain the best view of the uterus, ovaries and baby.2

If your ultrasound is performed between 5 and 6 weeks’ gestation, you will likely only be able to see the gestational and yolk sacs.2 The gestational sac is the sac in which your baby is growing.2 The yolk sac is a normal and positive finding during early pregnancy, as it allows your doctor or midwife to confirm your pregnancy, even though the baby may not be identifiable just yet.2  

If your ultrasound is completed between weeks 6 and 7, your baby (which is called an embryo), is measuring nearly 9 mm in length and measured in crown-rump-length (CRL); typically, a heartbeat is seen within this timeframe.2

Ultrasounds completed during 8 to 11 weeks will show your growing baby, which during this time has identifiable features such as the body, head, arms, and legs, and is moving quite readily within the gestational sac.2

Your doctor or midwife will discuss with you in detail the need for more frequent ultrasound evaluations based on your personal situation. Additional ultrasounds may be recommended in certain cases, especially if your pregnancy is categorized as high-risk, or if you are undergoing procedures such as chorionic villus sampling, an amniocentesis, nuchal translucency screening and/or biophysical profiles.1

Why Are Ultrasounds Done?

First trimester ultrasounds can be done for a variety of reasons including:

  • To correctly date your pregnancy to determine how far along you are1,2
  • Evaluate the size of the baby and characteristics of the baby’s gestational sac, such as size and appearance.2 At times, the gestational sac can be seen as early as 4 ½ weeks gestation1
  • Detect the heartbeat, which can be seen as early as 5-7 weeks gestation1,2
  • Confirm that the baby is growing within the uterus and not in another structure like the fallopian tube1,2
  • Evaluate the presence of multiple babies, especially in women who underwent IVF or other assistive fertility treatments.1,2 If twins are present, their type can be identified during this scan as well2
  • Determine miscarriage or pregnancy loss risk by evaluating for the presence of any abnormalities which would increase a woman’s risk for miscarriage2
  • Evaluation of the ovaries and uterus for abnormalities, such as uterine fibroids or ovarian cysts, for example2
  • Used as an evaluative tool for abdominal pain or vaginal bleeding1,2
  • Locate a pre-conception IUD1

Potential Risks

While an ultrasound is felt to be a very low-risk procedure, they are only recommended when medically necessary by both the American Congress of Obstetricians and Gynecologists and the Food and Drug Administration, because there are no studies to document long-term effects of ultrasound exposure, if any.1 They also advise against the use of at-home fetal monitors and keepsake 3-D and 4-D ultrasounds.1

Be sure to speak with your doctor or midwife about your specific ultrasound needs.1

 

The information included in this article and on this site is for educational purposes only. It is not intended nor implied to be a substitute for professional medical advice. You should always consult your healthcare provider to determine the appropriateness of the information for your own situation.

 
References:

  1. Ultrasound During Pregnancy. http://www.whattoexpect.com/pregnancy/pregnancy-health/prenatal-testing/ultrasound.aspx Accessed March 23, 2016
  2. First Trimester/Dating Ultrasound. http://www.advancedwomensimaging.com.au/first-trimester-dating-ultrasound Accessed March 23, 2016

The First Trimester Ultrasound

04/26/2016 - Contributed by: vitaMedMD

First trimester ultrasound

Prenatal care is vital to the health and wellbeing of you and your unborn baby, and often an important part of prenatal care may include an evaluation with ultrasound. Many expectant parents are delighted for the opportunity to see their growing baby, yet the experience can be accompanied by a variety of emotions and questions.

Some questions may include:

Why am I having an ultrasound? When will I have an ultrasound? What will it be like? What will my baby look like?

What to Expect During Your First Trimester Ultrasound

Typically, the first ultrasound will be done anytime within the first trimester of pregnancy.1,2 Most often, ultrasounds during pregnancy will be done externally with a transabdominal wand with gel; however, earlier on in the first trimester, it may be necessary to complete the ultrasound transvaginally.1,2 During a transvaginal ultrasound, a wand covered with a condom and gel, is placed in the vagina to allow for early visualization of the baby.1,2 If a transabdominal ultrasound is done, the bladder typically needs to be full to obtain the best view of the uterus, ovaries and baby.2

If your ultrasound is performed between 5 and 6 weeks’ gestation, you will likely only be able to see the gestational and yolk sacs.2 The gestational sac is the sac in which your baby is growing.2 The yolk sac is a normal and positive finding during early pregnancy, as it allows your doctor or midwife to confirm your pregnancy, even though the baby may not be identifiable just yet.2  

If your ultrasound is completed between weeks 6 and 7, your baby (which is called an embryo), is measuring nearly 9 mm in length and measured in crown-rump-length (CRL); typically, a heartbeat is seen within this timeframe.2

Ultrasounds completed during 8 to 11 weeks will show your growing baby, which during this time has identifiable features such as the body, head, arms, and legs, and is moving quite readily within the gestational sac.2

Your doctor or midwife will discuss with you in detail the need for more frequent ultrasound evaluations based on your personal situation. Additional ultrasounds may be recommended in certain cases, especially if your pregnancy is categorized as high-risk, or if you are undergoing procedures such as chorionic villus sampling, an amniocentesis, nuchal translucency screening and/or biophysical profiles.1

Why Are Ultrasounds Done?

First trimester ultrasounds can be done for a variety of reasons including:

  • To correctly date your pregnancy to determine how far along you are1,2
  • Evaluate the size of the baby and characteristics of the baby’s gestational sac, such as size and appearance.2 At times, the gestational sac can be seen as early as 4 ½ weeks gestation1
  • Detect the heartbeat, which can be seen as early as 5-7 weeks gestation1,2
  • Confirm that the baby is growing within the uterus and not in another structure like the fallopian tube1,2
  • Evaluate the presence of multiple babies, especially in women who underwent IVF or other assistive fertility treatments.1,2 If twins are present, their type can be identified during this scan as well2
  • Determine miscarriage or pregnancy loss risk by evaluating for the presence of any abnormalities which would increase a woman’s risk for miscarriage2
  • Evaluation of the ovaries and uterus for abnormalities, such as uterine fibroids or ovarian cysts, for example2
  • Used as an evaluative tool for abdominal pain or vaginal bleeding1,2
  • Locate a pre-conception IUD1

Potential Risks

While an ultrasound is felt to be a very low-risk procedure, they are only recommended when medically necessary by both the American Congress of Obstetricians and Gynecologists and the Food and Drug Administration, because there are no studies to document long-term effects of ultrasound exposure, if any.1 They also advise against the use of at-home fetal monitors and keepsake 3-D and 4-D ultrasounds.1

Be sure to speak with your doctor or midwife about your specific ultrasound needs.1

 

The information included in this article and on this site is for educational purposes only. It is not intended nor implied to be a substitute for professional medical advice. You should always consult your healthcare provider to determine the appropriateness of the information for your own situation.

 
References:

  1. Ultrasound During Pregnancy. http://www.whattoexpect.com/pregnancy/pregnancy-health/prenatal-testing/ultrasound.aspx Accessed March 23, 2016
  2. First Trimester/Dating Ultrasound. http://www.advancedwomensimaging.com.au/first-trimester-dating-ultrasound Accessed March 23, 2016