Multiple Pregnancy Scan And Evaluation
Multiple pregnancy is a condition where there are more than one fetus developing simultaneously in the mother’s womb. These pregnancies need a lot of special care in view of the risks associated with such pregnancies.
In multiple pregnancies it is very important to evaluate the chorionicity and amnionicity as early as possible.
Ultrasound diagnosis of Chorionicity and amnionicity should be done best before 16 weeks gestation.
Based on chorionicity the care plan varies as such –
Monochorionic twin pregnancies may sometimes be associated with complications such as TTTS, TRAP, TAPS etc. In such cases timely fetal interventions are required.
Monochorionic Twin Pregnancy
11-14 weeks
• Dating, laheling
• ChorionicitY
• Screening for trisomy 21
16 weeks
18 weeks
• Fetal growth, DVP
• UA-PI
20 wecks
• Detailed anatomy
• Biometry
• UA-PI, MCA-PSV
• Cervical length
22 weeks
24 weeks
26 weeks
28 weeks
30 weeks
• Fetal Growth, DVP
• UA-PI, MCA-PSV
32 weeks
34 weeks
36 weeks
Ultrasound Monitoring Pathway In Uncomplicated Monochorionic Twin Pregnancy. DVP (Deepest Vertical Pocket), MCA (Middle Cerebral Artery), Pl (Pulsatility Index), PSV (Peak Systolic Velocity), UA (Umbilical Artery).
Even the screening options vary for multiple gestation.
SCREENING FOR FETAL ANEUPLOIDIES.
TWIN PREGNANCIES:
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Combined screening (maternal age, NT, 1st Trimester Biochemical markers)
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SECOND TRIMESTER SCREENING CANNOT BE OFFERED
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NIPT - useful as a TRIAGE method in high risk cases
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Double amniocentesis.
TRIPLET / HIGHER ORDER:
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Only Ultrasound screening. NO BIOCHEMICAL SCREENINGS SHOULD BE DONE.
Dichorionic Twin Pregnancy
11-14 weeks
• Dating, laheling
• ChorionicitY
• Screening for trisomy 21
20-22 weeks
• Detailed anatomy
• Biometry
• Amniotic fluid volume
• Cervical Icissch
24-26 wecks
28-30 weeks
32-34 weeks
• Assessment of fetal growth
• Annioric fluid volume
• Fetal Doppler
36-37 weeks
Delivery
Ultrasound Monitoring Pathway In Uncomplicated
Dichorionic Twin Pregnancy.