4 doctors weighed in:
At which week does the fetus' brain start developing?
4 doctors weighed in

Dr. Allen Seely
General Practice
2 doctors agree
In brief: RIGHT AWAY
The fifth week of pregnancy, or the third week after conception, marks the beginning of the embryonic period.
This is when the baby's brain, spinal cord, heart and other organs begin to form.

In brief: RIGHT AWAY
The fifth week of pregnancy, or the third week after conception, marks the beginning of the embryonic period.
This is when the baby's brain, spinal cord, heart and other organs begin to form.
Dr. Allen Seely
Dr. Allen Seely
Thank
Dr. Nikolaos Zacharias
Obstetrics & Gynecology - Maternal Fetal Medicine
In brief: Before you know it.
Neurulation starts soon after conception and many open neural tube defects occur before you know you are pregnant.
That is the reason all sexually active women should be on folate (folic acid) during their reproductive years (or until menopause, hysterectomy, or bilateral tubal ligation) regardless of pregnancy plans. The brain development continues in utero until delivery and postnatally for many more years..

In brief: Before you know it.
Neurulation starts soon after conception and many open neural tube defects occur before you know you are pregnant.
That is the reason all sexually active women should be on folate (folic acid) during their reproductive years (or until menopause, hysterectomy, or bilateral tubal ligation) regardless of pregnancy plans. The brain development continues in utero until delivery and postnatally for many more years..
Dr. Nikolaos Zacharias
Dr. Nikolaos Zacharias
Thank
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