Ultrasound Timeline in Pregnancy
Early First Trimester: In the first trimester, ultrasound exams are done to demonstrate the viability of the pregnancy. A heartbeat can be detected at about 6 weeks menstrual age. This is also the most accurate time to date the pregnancy.
11-13 Weeks: A new genetic screen is now available called an Ultrascren that is used at 11 to 13 weeks to assess the likelihood of any chromosomal abnormalities. In the hands of an experienced sonographer, its detection rate is 91-95%.
19-20 Weeks: Most women will have a scan at the halfway point of their pregnancies, which is an ideal time to learn a wealth of information about the pregnancy. To date the pregnancy, measurements are taken of the fetal head, abdomen and femur.
The placenta location is noted, because a placenta positioned over the cervix (placenta previa) is a life-threatening condition for both mother and baby. The cervical length is measured, indicating the probability of pre-term labor.
Technological advancement has greatly improved the visibility of fetal anatomy during the second trimester. The fetal brain is evaluated for proper development, as well as the face, spine, arms, legs, hands, feet, stomach, kidney, bladder and umbilical cord. With the latest high-resolution equipment, even subtle abnormalities, such as cleft lip or club foot, ar apparent.
Virtually all congenital heart defects are detected now, with the heartbeat heard and all four chambers of the heart seen. It is now also possible to see the aorta rising from the left ventricle and the pulmonary artery from the right, as well as the returning veins into the right and left aorta with its branches.
Finally, this is the time when fetal gender is easily determined for parents who want to know.
26-30 Weeks: This is the optimal time during pregnancy to get a 3D/4D ultrasound of your baby. Plenty of fluid makes for good viewing, and the baby is big enough to show his or her unique physical features. The newest machines provide not only photos, but DVD’s of your baby living and moving in the womb.
Third Trimester: Ultrasound exams at this stage of pregnancy are usually reserved for those where there is a concern. The healthcare provider questions the growth or well-being of the baby, or the development of a condition in the mother, such as gestational diabetes or elevated blood pressure.
Sound Health Imaging employs only registered monographers and the newest ultrasound technology available.
Lightest Births….. The lowest birth weight recorded for a surviving infant, of which there is definite evidence is 9.17 ounces in the case of Rumaisa Rahman who was born at Loyola University Medical Center, Maywood, Illinois, on September 19, 2004 at a gestational age of 25 weeks 6 days.
Heaviest Births…. Anna Bates (1846-1888) who measured 7ft. 5.5 inches tall, gave birth to a baby boy 23 lb 12 oz. and measuring 30 inches long, at her home in Seville, Ohio, on January 19, 1879. The baby lived only 11 hours.
The heaviest baby born to an average sized mother was a boy weighing 22 pounds 8 ounces who was born to Carmelina Fedele at Aversa, Italy in September 1955.
A letter to the British Medical Journal February 1, 1879 from a doctor in Torpoint, Cornwall, UK, reported that a child born on Christmas Day 1852 weighed 21 pounds.
On March 9, 1992 the eighth child of Andrew and Nicola Carr (5ft2in. tall) was born weighing 15 1/2 pounds 25 inches long.
Multiple Births. . . . Most surviving children from a single birth, 4 boys and 3 girls born to Bobbie McCaughey on November 19, 1997 in Iowa. Conceived by in-vitro fertilization.
Frequently Asked Questions about OB Ultrasound
Why do I need to fill my bladder for an OB/Gyn ultrasound exam?
A full bladder is the “window to the womb” and helps visualization of the lower uterine segment and cervix. A full bladder also helps to move the baby out of the deep pelvis for better visualization.
How much and what do I need to drink to fill my bladder?
We recommend drinking 24 ounces, finishing 45 minutes before your appointment. You can drink any kind of clear liquid, including pop, tea, juice or water. No milk products, as they do not fill the bladder.
When can you tell the baby's gender on an ultrasound?
During the 20 week ultrasound gender is readily visible. In rare instances the baby is in a poor position and gender cannot be determined. In those situations, if the parents want to know, we invite the mom back at a later date at no extra charge to determine baby’s gender.
Who can come into the ultrasound exam with me?
We allow anyone in the exam room the mom wishes to invite.
Can we bring children for the ultrasound appointment?
Children are welcome if another adult is along to provide supervision. The 20 week fetal survey scan takes approximately 45-60 minutes to complete, and small children might get bored. Our waiting room has a TV with cartoons and a toy box. We try to be kid friendly!
How do I schedule my ultrasound appointment at Sound Health Imaging?
You have a choice where your ultrasound is done. Tell your healthcare provider that you would like to have them your ultrasound scheduled at Sound Health Imaging. Or you can call our office and schedule your ultrasound exam and then bring your Doctor’s order with you at the time of exam.