6 doctors weighed in:

What could a small head on fetal ultrasound be a sign of?

6 doctors weighed in
Dr. Nikolaos Zacharias
Obstetrics & Gynecology - Maternal Fetal Medicine
4 doctors agree

In brief: Wrong dates!

The most common reason for suspected fetal microcephaly is erroneous due date assignment.
If microcephaly is real, it could be part of several fetal syndromes with poor neurodevopmental outcome, such as aneuploidies (down), perinatal infections (toxoplasmosis, rubella, cmv), or metabolic disorders.

In brief: Wrong dates!

The most common reason for suspected fetal microcephaly is erroneous due date assignment.
If microcephaly is real, it could be part of several fetal syndromes with poor neurodevopmental outcome, such as aneuploidies (down), perinatal infections (toxoplasmosis, rubella, cmv), or metabolic disorders.
Dr. Nikolaos Zacharias
Dr. Nikolaos Zacharias
Thank
3 doctors agree

In brief: Microcephaly

Microcephaly which could portend poor intellectual development.

In brief: Microcephaly

Microcephaly which could portend poor intellectual development.
Dr. Arnold Friedman
Dr. Arnold Friedman
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Dr. Johanna Fricke
Pediatrics - Developmental & Behavioral
1 doctor agrees

In brief: As answered, plus

What's important is to have at least 2 more measurements to determine velocity of head & body growth.
Any measurement <5th %ile means there's a chance of a problem, but it doesn't tell you if the problem is fetal, placental or maternal. If you didn't smoke, drink or use drugs from the date of conception ( not from date of pregnancy diagnosis) , you've done nothing to cause this.

In brief: As answered, plus

What's important is to have at least 2 more measurements to determine velocity of head & body growth.
Any measurement <5th %ile means there's a chance of a problem, but it doesn't tell you if the problem is fetal, placental or maternal. If you didn't smoke, drink or use drugs from the date of conception ( not from date of pregnancy diagnosis) , you've done nothing to cause this.
Dr. Johanna Fricke
Dr. Johanna Fricke
Thank
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