Monochorionic Twin Pregnancy Scan in Nagpur
Monochorionic twins share one placenta. Because their circulation may be connected through the placenta, they need a planned fetal medicine surveillance schedule from early pregnancy, especially from 16 weeks onwards.
Why monochorionic twins need specialist follow-up
In monochorionic twin pregnancy, both babies share one placenta. This shared placental circulation can create complications that are not seen in ordinary singleton pregnancies and are different from most dichorionic twin pregnancies.
Dr. Kunda Shahane evaluates each twin separately and also looks at the relationship between the two babies — fluid around each twin, bladder filling, growth difference, Doppler, fetal heart views and early signs of TTTS, TAPS or selective growth restriction.
What does monochorionic mean?
Monochorionic means the twins share one placenta. The amniotic sac pattern may still be different.
Monochorionic diamniotic twins
The twins share one placenta but have two separate amniotic sacs. This is the commoner form of monochorionic twin pregnancy.
Monoamniotic twins
The twins share one placenta and one amniotic sac. This is rare and needs very high-risk monitoring because both babies are in the same sac.
Best diagnosed early
Chorionicity and amnionicity are best documented in the first trimester, when the membrane and placental signs are clearer.
Do not delay chorionicity confirmation
If your report says “monochorionic twins,” “shared placenta,” “MCDA,” or “MCMA,” the pregnancy needs a twin-specific fetal medicine plan. If your report does not clearly mention chorionicity, get it reviewed as early as possible.
What is checked in a monochorionic twin scan?
Every scan is not just a “growth scan.” It is a targeted shared-placenta surveillance visit.
| Scan component | What Dr. Kunda checks | Why it matters in monochorionic twins | Possible concern detected |
|---|---|---|---|
| Amniotic fluid around each twin | Deepest vertical pocket for Twin A and Twin B, membrane clearly seen between pockets. | Unequal fluid can be one of the earliest signs of TTTS. | TTTS Fluid imbalance |
| Bladder visibility | Whether each twin’s bladder is visible and filling during the scan. | Absent or very small bladder in one twin, with fluid imbalance, can be important in TTTS staging. | Donor twin concern |
| Growth of each twin | BPD, HC, AC, FL and estimated fetal weight for each baby. | Growth difference can suggest selective fetal growth restriction or placental sharing imbalance. | Growth discordance sFGR |
| Umbilical artery Doppler | Blood flow resistance in each twin’s umbilical artery. | Abnormal flow may suggest placental insufficiency or severe selective growth restriction. | Abnormal placental flow |
| MCA Doppler / MCA-PSV | Middle cerebral artery peak systolic velocity when TAPS or anemia/polycythemia concern is present. | MCA-PSV helps screen selected monochorionic twins for anemia/polycythemia pattern. | TAPS |
| Ductus venosus Doppler | Ductus venosus flow in selected high-risk or abnormal cases. | Useful when there is severe TTTS, growth restriction or cardiac strain concern. | Cardiac strain |
| Fetal heart views | Four-chamber view, outflow tracts, rhythm and cardiac function screening; fetal echo if needed. | Monochorionic twins have higher cardiac surveillance needs, especially if TTTS is suspected. | Fetal echo need |
| Cord insertion and placenta | Cord insertion for each twin, placental sharing clues and membrane insertion. | Unequal placental sharing and abnormal cord insertion can influence growth and Doppler. | Placental sharing issue |
| Cervical length / preterm risk | Cervical length assessment in selected cases based on symptoms, history or scan findings. | Twins have higher preterm birth risk, and monochorionic complications may need earlier delivery planning. | Preterm birth risk |
Why 2-weekly surveillance matters
In monochorionic twins, fluid, bladder and Doppler changes can appear within a short interval. Regular surveillance helps detect TTTS, TAPS and selective growth restriction before the pregnancy becomes an emergency.
TTTS and TAPS screening is the heart of monochorionic monitoring
TTTS is screened mainly through fluid difference, bladder visibility, fetal growth and Doppler findings. TAPS screening may require MCA Doppler assessment when clinically indicated.
If a concerning pattern is seen, the priority is not panic. The priority is correct staging, counselling and timely referral or intervention planning.
Complications monitored in shared-placenta twins
The goal is early recognition, correct staging and coordinated pregnancy planning.
TTTS
Twin-to-twin transfusion syndrome occurs when blood flow through shared placental connections becomes unbalanced.
TAPS
Twin anemia-polycythemia sequence may develop with very small placental vessel connections and may need MCA Doppler screening.
Selective FGR
One twin may grow significantly less due to unequal placental sharing, abnormal cord insertion or placental blood flow differences.
TRAP sequence
Rarely, monochorionic twins may have abnormal circulation patterns such as twin reversed arterial perfusion sequence, requiring specialist review.
Typical monochorionic twin scan pathway
First trimester: dating, viability and chorionicity
The scan confirms gestational age, number of babies, placental sharing, membrane pattern and early fetal assessment.
11–14 weeks: NT scan and early anatomy
NT scan, early anatomy, chorionicity confirmation and risk assessment are reviewed for each twin.
From 16 weeks: regular TTTS/TAPS surveillance
Uncomplicated monochorionic twins usually need ultrasound surveillance every 2 weeks from 16 weeks, with more frequent review if abnormal findings appear.
18–22 weeks: detailed anomaly scan
Both twins are assessed separately for anatomy, fetal heart views, placenta, cord insertion, cervix and twin-specific concerns.
Third trimester: growth, Doppler and wellbeing planning
Growth discordance, Doppler, amniotic fluid, NST/BPP when needed, fetal presentation and delivery planning are reviewed.
Do not wait for the next routine scan if symptoms appear
Reduced fetal movements
Reduced movement of either twin should be discussed urgently with your obstetrician or nearest hospital.
Sudden abdominal tightness or pain
Pain, contractions, fluid leakage or bleeding in twin pregnancy needs prompt clinical assessment.
Abnormal scan findings
Fluid difference, absent bladder, abnormal Doppler, major growth discordance or hydrops should be reviewed without delay.
What to bring for your appointment
Bring early pregnancy scan images, chorionicity report, NT scan report, anomaly scan report, Doppler reports, fetal echo if done, IVF records if applicable, blood pressure/sugar records and all obstetric notes.
Dr. Kunda Shahane’s note on monochorionic twins
“In monochorionic twin pregnancy, the placenta is shared, so we monitor not only each baby separately but also the balance between the two. Fluid, bladder, growth and Doppler patterns can change quickly. A fixed surveillance schedule from 16 weeks helps us detect problems early and act at the right time.”
Monochorionic twin pregnancy FAQs
Are monochorionic twins always identical?
Monochorionic twins usually arise from one embryo and are typically identical, but the clinically important point is that they share one placenta and need closer surveillance.
What is the difference between MCDA and MCMA twins?
MCDA twins share one placenta but have two amniotic sacs. MCMA twins share one placenta and one amniotic sac. MCMA twins are rarer and need even closer specialist care.
When should monochorionic twin scans start?
Chorionicity should be assessed in the first trimester. Regular monochorionic surveillance usually starts from around 16 weeks.
How often should monochorionic twins be scanned?
In uncomplicated monochorionic twins, scans are commonly planned every 2 weeks from 16 weeks. Complicated cases may need more frequent review.
What is checked for TTTS?
TTTS screening checks amniotic fluid around each twin, bladder visibility, fetal growth, Doppler and signs of fetal strain or hydrops.
What is checked for TAPS?
TAPS screening may include MCA Doppler to assess whether one twin shows an anemia pattern and the other shows a polycythemia pattern.
Do monochorionic twins need fetal echo?
Fetal echocardiography may be advised when cardiac views are incomplete, a heart concern is seen, TTTS is suspected, or the fetal medicine specialist recommends detailed cardiac assessment.
Can monochorionic twins be delivered normally?
Delivery planning depends on gestational age, fetal presentation, growth, Doppler, TTTS/TAPS status, obstetric history and the treating obstetrician’s assessment. The scan helps guide planning but does not decide delivery mode alone.
Internal links for this page
Need monochorionic twin pregnancy monitoring in Nagpur?
Book a specialist monochorionic twin pregnancy scan and counselling appointment with Dr. Kunda Shahane at Mayflower Fetal Medicine & High-Risk Pregnancy Centre, Dhantoli, Nagpur. Carry your earliest scan report so chorionicity and the follow-up schedule can be planned correctly.
Latest Posts
-
Fetal Echocardiography: Detecting Heart Defects before Birth
Fetal Echocardiography: Detecting Heart Defects before Birth…
-
High-Risk Pregnancy: How Fetal Medicine Supports Moms and Babies
High-Risk Pregnancy: How Fetal Medicine Supports Moms…