Which of the following statements about chorionic villus sampling is false?
All are true about uteroplacental circulation except:
Common misdiagnosis of partial mole is
A G2P1L1 female presents at 28 weeks of gestation with a 1:4 anti-D titre. What is the most appropriate management option?
Which of the following is NOT a cause of oligohydramnios?
Which of the following statements about abdominal pregnancy is true?
Most common antigen involved in erythroblastosis fetalis is:
A 28-year-old primigravida with 32 weeks of gestation presents with profuse vaginal discharge since yesterday. She was advised USG, which showed a single live intrauterine gestational sac with FL and AC corresponding to the weeks of gestation and AFI as adequate. What is the diagnosis?
What is the best initial management option for ovarian ectopic pregnancy?
Uterine height is greater than gestational age of the patient in a case of all except -
Explanation: ***Is performed only in second trimester of pregnancy*** - This statement is false because **chorionic villus sampling (CVS)** is typically performed earlier in pregnancy, specifically during the **first trimester**, usually between 10 and 13 weeks of gestation. - Performing CVS only in the second trimester would negate one of its main advantages: providing earlier genetic diagnostic information than **amniocentesis**. *Is used for prenatal genetic diagnosis* - **CVS** is a primary method for **prenatal genetic diagnosis**, allowing for the detection of chromosomal abnormalities and genetic disorders. - It involves analyzing fetal cells obtained from the **chorionic villi**. *Villi are collected from chorion frondosum* - The sample for **CVS** is indeed collected from the **chorion frondosum**, which is the fetal part of the placenta containing numerous chorionic villi. - These villi are genetically identical to the fetus, making them suitable for **genetic analysis**. *Can cause limb deformities* - There is a recognized, albeit small, risk of **limb reduction defects** associated with CVS, particularly if performed very early in gestation (before 9-10 weeks). - This risk is part of the counseling provided to prospective parents considering the procedure.
Explanation: ***A mature placenta has 150 ml of blood in the villi system and 350 ml of blood in the intervillous space*** - This statement is incorrect because a **mature placenta** typically holds approximately **350 ml of blood** in the **villi system** and **150 ml of blood** in the **intervillous space**, which is the reverse of what is stated. - The villi system contains the fetal blood, which has a larger volume within the placental unit. *Blood in the intervillous space is completely replaced 3-4 times per minute* - This is a correct statement regarding uteroplacental circulation, as the **high turnover rate** ensures efficient **nutrient and gas exchange** between mother and fetus. - The rapid replacement prevents stagnant blood and facilitates continuous delivery of essential substances. *The villi depend on the maternal blood for their nutrition* - This statement is true because the **chorionic villi**, which are the functional units of the placenta, are bathed in **maternal blood** within the intervillous space. - The placental tissue itself receives its **nutrients and oxygen** directly from this maternal blood supply. *Intervillous blood flow at term is 500-600 ml per minute* - This is an accurate physiological fact. At term, the **maternal blood flow** through the intervillous space is indeed substantial, typically ranging from **500 to 700 ml per minute**, ensuring adequate perfusion for the growing fetus. - This significant blood flow is crucial for meeting the high metabolic demands of the fetus.
Explanation: ***Threatened abortion*** - Partial moles often present with **vaginal bleeding** and a uterus size appropriate for gestational age, mimicking the symptoms of a **threatened abortion**. - **Fetal heartbeat** may be detectable in a partial mole, further complicating differentiation from a threatened abortion without detailed ultrasound or histological examination. *Choriocarcinoma* - **Choriocarcinoma** is a malignant tumor and a complication of molar pregnancy, not a common misdiagnosis of an early partial mole. - While both involve abnormal trophoblastic tissue, **choriocarcinoma** follows a molar pregnancy (or other gestations) and presents with systemic symptoms and very high hCG levels, distinct from the initial presentation of a partial mole. *Complete mole* - **Complete moles** are distinct from partial moles both genetically (46,XX or 46,XY with paternal origin only) and pathologically (no fetal tissue, generalized hydropic villi). - While both are types of molar pregnancy, they have different management and prognostic implications, and are distinct entities rather than a misdiagnosis of one for the other's initial presentation. *Ectopic pregnancy* - An **ectopic pregnancy** typically presents with pain and vaginal bleeding, along with an empty uterus on ultrasound. - While both involve abnormal pregnancy presentations, a **partial mole** usually shows some fetal tissue or identifiable placental tissue within the uterine cavity, distinguishing it from an ectopic pregnancy.
Explanation: ***MCA Doppler*** - The presence of anti-D antibodies in a pregnant woman indicates **Rh isoimmunization**, which can lead to **hemolytic disease of the fetus and newborn (HDFN)**. - Even though a titre of **1:4 is below the critical threshold** (usually 1:16 or 1:32), any detectable anti-D titre at 28 weeks warrants **fetal surveillance** to detect early signs of fetal anemia. - **Middle cerebral artery (MCA) Doppler** is the **non-invasive gold standard** for detecting fetal anemia by measuring peak systolic velocity (PSV), which increases in anemic fetuses due to hyperdynamic circulation. - Serial MCA Doppler monitoring allows timely intervention if fetal anemia develops, avoiding unnecessary invasive procedures. *Caesarean section* - This is a mode of delivery and would only be considered if there were severe **fetal compromise** or other obstetric indications after proper monitoring and management. - At 28 weeks gestation with a low anti-D titre, immediate delivery is **not indicated** and would result in significant prematurity risks. *Induction of labour* - Induction of labour is a delivery method that would only be planned at term or for specific indications like severe fetal compromise unresponsive to other interventions. - At **28 weeks gestation**, the focus should be on **monitoring and prolonging pregnancy** while ensuring fetal wellbeing, not on delivery. *Amniocentesis* - Historically used to assess **bilirubin levels (ΔOD450)** in amniotic fluid as an indirect measure of fetal hemolysis, but it is an **invasive procedure** with risks (miscarriage ~1%, infection, worsening sensitization). - **MCA Doppler has largely replaced amniocentesis** for initial and serial assessment of fetal anemia due to its non-invasive nature, high sensitivity, and ability to be repeated safely.
Explanation: ***Chorioangioma*** - A **chorioangioma** is a benign placental tumor that causes **polyhydramnios** (excess amniotic fluid), which is the **opposite** of oligohydramnios. - Large chorioangiomas lead to increased transudation from the tumor's vascular channels, fetal anemia, and high-output cardiac failure, resulting in increased fetal urine production. - This is clearly **NOT a cause** of oligohydramnios, making it the correct answer. *IUGR* - **Intrauterine growth restriction (IUGR)**, particularly with placental insufficiency, is a common cause of **oligohydramnios**. - Reduced placental perfusion leads to decreased **fetal renal blood flow** and diminished urine production. - Since fetal urine is the main source of amniotic fluid after 16 weeks, reduced output causes oligohydramnios. *Renal agenesis* - **Bilateral renal agenesis** (Potter syndrome) is a classic and severe cause of **oligohydramnios/anhydramnios**. - Complete absence of kidneys means **no fetal urine production**, eliminating the primary source of amniotic fluid in the second and third trimesters. - Results in severe oligohydramnios with associated pulmonary hypoplasia and Potter facies. *Amnion nodosum* - **Amnion nodosum** refers to small, grayish-yellow nodules on the fetal surface of the amnion, composed of aggregated fetal squamous epithelial cells and vernix. - These nodules are a **pathological finding** that occurs as a **consequence** of chronic oligohydramnios, not a cause. - They form due to prolonged contact between the fetal skin and amnion when amniotic fluid is severely reduced. - While technically "not a cause," it is strongly **associated with** oligohydramnios, whereas chorioangioma causes the opposite condition entirely.
Explanation: ***f6629bc8-61b2-4393-bb4c-9c32cd943e34*** - **Placenta acreta-like implantation** of the placenta into intra-abdominal organs or the abdominal wall makes removal dangerous due to potential damage and massive hemorrhage. - While leaving it in place can lead to serious complications like **infection**, **abscess formation**, or **secondary hemorrhage** as it degenerates, the risks of immediate removal often outweigh these, necessitating careful observation and management. *020c0067-d7b2-4fc2-85ae-2d6ba40ab437* - **Primary abdominal pregnancy** is extremely rare, accounting for less than 1% of all extrauterine pregnancies. - Abdominal pregnancies are generally **secondary** due to tubal abortion or rupture with subsequent reimplantation. *3560b92d-a63d-4966-8872-e4f56a82882f* - **Fetal survival rates** in abdominal pregnancies are very low, with a high incidence of **fetal anomalies** and **perinatal mortality**. - The abnormal placental implantation and lack of amniotic fluid protection lead to significant **growth restriction** and compression deformities. *5ab987e0-68ca-43f2-a8f2-238a5eb0c4f8* - The decision to remove the **placenta** in an abdominal pregnancy is complex and depends on its implantation site; often, it is left in situ due to the high risk of **hemorrhage** from attempting removal. - Removing the placenta can cause **uncontrollable bleeding**, especially if it is attached to vital organs or large blood vessels.
Explanation: ***D antigen in Rh group*** - The **D antigen** is the most immunogenic of the Rh antigens and is responsible for the vast majority of cases of **erythroblastosis fetalis** (hemolytic disease of the fetus and newborn). - When an **Rh-negative mother** is exposed to Rh-positive fetal blood (usually during previous pregnancies or transfusions), she can form antibodies against the D antigen, which can then cross the placenta in subsequent pregnancies and attack Rh-positive fetal red blood cells. *C antigen in Rh group* - While the **C antigen** is part of the Rh blood group system, antibodies to it are much less common and typically cause less severe hemolytic disease compared to anti-D antibodies. - The C antigen is less immunogenic than the D antigen, meaning it is less likely to provoke an immune response in an Rh-negative individual. *E antigen in Rh group* - Similar to the C antigen, the **E antigen** is another Rh antigen, but antibodies against it (anti-E) are also less frequently implicated in severe erythroblastosis fetalis than anti-D. - Antibodies to E can cause hemolytic disease, but their clinical significance is usually milder than that of anti-D. *Duffy antigen* - The **Duffy antigen system** is separate from the Rh system and is known for its role in resistance to certain malarial parasites (e.g., *Plasmodium vivax*). - Although antibodies to Duffy antigens (anti-Fya, anti-Fyb) can cause **hemolytic disease of the fetus/newborn**, they are a far less common cause of erythroblastosis fetalis than antibodies to the Rh D antigen.
Explanation: ***Normal vaginal discharge*** - Profuse vaginal discharge is a common and **physiological occurrence** in pregnancy due to increased estrogen levels and blood flow to the vagina. - The ultrasound findings of **adequate amniotic fluid index (AFI)** rule out rupture of membranes, and no other symptoms of infection are reported. *Preterm Premature Rupture of Membranes (PPROM)* - PPROM would present with a significant reduction in the **amniotic fluid index (AFI)** on ultrasound, which is noted as adequate in this case. - The discharge in PPROM is typically **amniotic fluid**, which is clear and watery, unlike mere profuse vaginal discharge. *Trichomoniasis* - This infection typically causes a **frothy, greenish-yellow discharge** with a foul odor, along with vulvar itching and irritation. - These characteristic symptoms are not mentioned in the patient's presentation. *Candidiasis* - Vaginal candidiasis usually presents with a **thick, white, cottage cheese-like discharge** accompanied by intense itching and burning. - The patient's description of discharge is simply "profuse," without these specific characteristics.
Explanation: ***Surgical management (laparoscopy if stable, laparotomy if unstable)*** - **Ovarian ectopic pregnancies** are best managed surgically due to the **high vascularity of the ovary** and significant risk of hemorrhage - The surgical approach is **individualized**: **laparoscopy** is preferred for hemodynamically **stable patients**, while **laparotomy** is indicated for **unstable patients** or those with suspected rupture and massive hemorrhage - Surgery allows for **definitive treatment** with ovarian wedge resection or oophorectomy while preserving fertility when possible *Medical management with methotrexate* - **Methotrexate** has been used in selected cases of ovarian ectopic pregnancy, but success rates are **lower than tubal ectopics** due to increased vascularity - The risk of **treatment failure** with subsequent rupture and hemorrhage limits its routine use - Generally reserved for very early, small, unruptured cases with low hCG levels in carefully selected patients *Expectant management with serial monitoring* - **Expectant management** is rarely appropriate for ovarian ectopic pregnancy due to the high risk of **rupture and life-threatening hemorrhage** - The **highly vascular nature** of ovarian tissue makes spontaneous resolution unpredictable and potentially dangerous - Not recommended as initial management except in rare cases with declining hCG and very small masses *Emergency laparotomy in all cases* - While surgical management is preferred, **laparotomy is not required in all cases** - Hemodynamically **stable patients** can be safely managed with **laparoscopy**, which offers faster recovery and less morbidity - **Emergency laparotomy** is reserved for hemodynamically **unstable patients** or those with signs of massive intraperitoneal hemorrhage
Explanation: ***IUGR*** - In **Intrauterine Growth Restriction (IUGR)**, the fetus is smaller than expected for gestational age, leading to a **fundal height** that measures less than the actual gestational age. - This condition is characterized by a **restricted growth rate** of the fetus, causing the uterine size to be disproportionately small. *Fibroid uterus* - The presence of **uterine fibroids** (leiomyomas) can increase the overall size of the uterus beyond what would be expected for a given gestational age. - These benign tumors add bulk to the uterine wall, leading to a **larger-than-expected uterine height**. *Wrong dates* - Incorrect estimation of the **Last Menstrual Period (LMP)** or date of conception can lead to a miscalculation of gestational age. - If the gestational age is **underestimated**, the actual uterine height will appear greater than the calculated gestational age. *Polyhydramnios* - **Polyhydramnios** is a condition characterized by an **excessive accumulation of amniotic fluid**, which distends the uterus. - Increased amniotic fluid volume leads to a significantly **larger uterine size** and a fundal height greater than the gestational age.
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Intrauterine Growth Restriction
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Multiple Gestation
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Rh Isoimmunization and Other Blood Group Incompatibilities
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Intrauterine Fetal Therapy
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Prenatal Diagnosis and Genetic Counseling
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Placental Abnormalities
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Preterm Labor and Delivery
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