15/07/2025
الزملاء الأفاضل
تلخيص مبسط
للأهمية البالغة
مقسم الي جزئين لعدم الاطالة
الجزء الأول
🍼 First Trimester Anomaly Scan
وما هي الخطوات المتبعة في حال اكتشاف اي خلل. في الجنين
First trimester anomaly scan scan
Often called the “early anatomy scan” or “11–14 week scan”, this includes:
• Timing: Done between 11 weeks and 13+6 weeks gestation.
♦️ Purpose:
Nuchal translucency (NT) measurement
* Basic structure anatomy check (brain, limbs, bladder, stomach, etc.).
* Early signs of anomalies (e.g., anencephaly, abdominal wall defects).
* Assess nasal bone, tricuspid flow, ductus venosus (for aneuploidy risk).
* Crown-rump length (CRL) for accurate dating
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🧬 Non-Invasive Prenatal Testing (NIPT)♦️
* Timing: From 10 weeks gestation onward.
* Sample: Maternal blood.
* Purpose: Screens for chromosomal aneuploidies like:
• Trisomy 21 (Down syndrome)
• Trisomy 18 and 13
• Sometimes s*x chromosomes (optional).
♦️ Advantages:
• No risk to pregnancy.
• High sensitivity/specificity.
• Limitations: It is a screen, not diagnostic—if positive, follow with CVS or amniocentesis.
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🧫 Chorionic Villus Sampling (CVS)
* Timing: 11–13 weeks gestation.
* How: Placental sample via transabdominal or transcervical needle.
* Purpose: Diagnostic for chromosomal abnormalities and genetic disorders (e.g., thalassemia, SMA).
♦️ Indications:
💥 High NT
💥 Positive NIPT
💥 Family history of genetic disease
💥 Parental chromosomal rearrangement
💥 Risk: ~0.5–1% miscarriage risk.
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💉 Amniocentesis♦️
* Timing: From 15–16 weeks gestation onward.
* How: Amniotic fluid sample via transabdominal needle.
* Purpose: Diagnostic (karyotype, microarray, infection, enzyme studies).
* Indications: Same as CVS, or when later confirmation is needed.
* Risk: ~0.1–0.3% miscarriage risk.
My best regards