First Trimester Obstetrics
The beginning of everything.
What to expect from the exam?
First trimester ultrasound is one of the most important tests during pregnancy. It provides essential information about the baby's early development and helps ensure that everything is going well in the first months of pregnancy.
When should it be carried out?
This test is recommended for pregnant women between 7 and 10 weeks, counted from the first day of the last menstrual period (LMP) or when the beta-hCG is above 2500 mIU/mL. It is generally the first ultrasound of pregnancy, performed after a positive pregnancy test.
What is evaluated?
During this ultrasound, we aim to confirm:
If the pregnancy is located inside the uterus (excluding ectopic pregnancy).
Presence of the gestational sac and the yolk sac.
Presence of the embryo with heartbeat.
Number of embryos (single or twin pregnancy).
More accurate gestational age, through the measurement of head-to-heel length (CCN).
Main complications.
This ultrasound is also important for early detection,
some situations that deserve attention:
Ectopic pregnancy outside the uterus
Anembryonic pregnancy (no visible embryo)
Missed or ongoing abortion.
Subcortical hematoma possible cause of bleeding at the beginning of pregnancy
Early detection of any change allows for quicker and more targeted care, protecting the health of the pregnant woman and the baby.
Why not do it earlier?
Seven weeks?
Before 7 weeks of pregnancy, it is often not possible to visualize the embryo or detect the heartbeat. This can cause unnecessary anxiety and the false impression that something is wrong, when in fact the pregnancy is still very early.
When to do it beforehand
Seven weeks?
When the patient presents bleeding or abdominal pain
When there is suspicion of ectopic pregnancy outside the uterus
In cases of in vitro fertilization or treatments to conceive
In these cases, early testing is done to ensure that the pregnancy is progressing well and that there are no health risks to the mother.
But, most of the time, the exam Will not show the embryo.
What can be seen?
Most of the time...
We measure the embryo from end to end. This measure is called CCN (head-to-heel length). Through it, we can see if the gestational age is compatible with the date of the last menstrual period (LMP).
The Vitelline Vesicle (VV) is this round structure. She is responsible for nourishing and providing oxygen to the baby in this beginning.
The Gestational Sac is this dark area, the amniotic fluid, where the baby will spend the nine months.
Heartbeats. The most anticipated moment for moms!
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