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OG9.1-6 | Early Pregnancy Complications — PBL Case

CLINICAL SETTING

Mrs Kamala Devi, a 29-year-old G3P2, is referred from a primary health centre to the obstetric outpatient department. The referring note states: 'Patient 14 weeks pregnant, uterus large for dates, vomiting not settling.' She is accompanied by her husband. She reports heavy vaginal bleeding with passage of grape-like vesicles over the past two days. She has been vomiting severely since 8 weeks and has lost approximately 4 kg from her pre-pregnancy weight. She denies abdominal pain but reports palpitations. Her blood pressure today is 152/96 mmHg. Her previous two pregnancies were uncomplicated vaginal deliveries. She is not on any medications. She appears pale and anxious. On abdominal examination, the uterine fundus reaches the umbilicus (approximately 20-week size). No fetal parts are palpable. Fetal heart sounds are not heard with a Pinard stethoscope. Her urine pregnancy test is strongly positive.

Trigger 1: Establishing the Diagnosis

The team orders a pelvic ultrasound. The report reads: 'Uterine cavity entirely filled with echogenic material showing a classic snowstorm pattern. No fetal parts identified. Bilateral ovarian cysts — right 7.2 cm and left 6.8 cm — multiloculated, with internal echoes. No free fluid in the peritoneum.' Serum beta-hCG returns at 380,000 mIU/mL. Thyroid function tests: TSH <0.01 mIU/L (suppressed), free T4 elevated at 28 pmol/L.

DISCUSSION POINTS

  • What is the most likely diagnosis, and what specific features of the clinical presentation, ultrasound, and beta-hCG result support it? Distinguish between complete and partial hydatidiform mole and explain which is more likely here.
  • What are bilateral theca lutein cysts, why do they form in this condition, and what is their clinical significance? Will they require separate treatment?
  • Why is Mrs Kamala's TSH suppressed? Explain the molecular basis for gestational thyrotoxicosis in molar pregnancy, and how this should be managed pre-operatively.
  • Why does she have hypertension at 14 weeks? What is the significance of pre-eclampsia before 20 weeks, and how does it help narrow the differential diagnosis?
Click to reveal Trigger 2: Pre-operative Preparation and the Evacuation Procedure (discuss previous trigger first!)

Trigger 2: Pre-operative Preparation and the Evacuation Procedure

The team decides on suction evacuation (vacuum aspiration). Her haemoglobin is 8.6 g/dL. Blood group is B negative. She is started on an oral beta-blocker for her thyrotoxicosis. The anaesthetist expresses concern about the large theca lutein cysts and asks whether they should be drained first. A junior resident asks: 'Should we give misoprostol for cervical priming and use oxytocin during the procedure?'

DISCUSSION POINTS

  • What are the specific pre-operative steps required before suction evacuation of a molar pregnancy? Include management of anaemia, thyrotoxicosis, blood group, and any blood product preparations.
  • Should the theca lutein cysts be drained surgically before or during the evacuation? Justify your answer.
  • Is oxytocin infusion during suction curettage of a molar pregnancy appropriate? What is the risk associated with using uterotonic agents before the uterine cavity is empty in a molar pregnancy?
  • What is the significance of her Rh-negative blood group in this procedure? Is anti-D prophylaxis indicated for molar pregnancy?
Click to reveal Trigger 3: Post-Evacuation Care and Counselling (discuss previous trigger first!)

Trigger 3: Post-Evacuation Care and Counselling

The evacuation is completed uneventfully. The specimen is sent for histopathology. The report confirms complete hydatidiform mole with diploid karyotype (46,XX). The anaemia is treated. Her BP normalises within 48 hours. She is ready for discharge. Her husband asks: 'Is she cured now? When can we try for another pregnancy?' You explain that follow-up is essential. The ward pharmacist informs you that she has been prescribed an oral contraceptive pill for follow-up.

DISCUSSION POINTS

  • Outline the beta-hCG surveillance protocol for post-molar follow-up: what frequency, for how long, and what constitutes 'normal' regression vs a GTN trigger? State the FIGO criteria for diagnosing gestational trophoblastic neoplasia.
  • Why is contraception recommended during hCG surveillance, and which method is preferred? Can Mrs Kamala use an intrauterine contraceptive device?
  • What are the factors in this case that classify this as a high-risk molar pregnancy, and what does this mean for her follow-up? (Consider uterine size, hCG level, theca lutein cysts, and maternal age.)
  • When can Mrs Kamala safely attempt another pregnancy? What is the risk that her next pregnancy will also be a molar pregnancy?
Click to reveal Trigger 4: Gestational Trophoblastic Neoplasia — When Surveillance Triggers Treatment (discuss previous trigger first!)

Trigger 4: Gestational Trophoblastic Neoplasia — When Surveillance Triggers Treatment

Six months later, Mrs Kamala returns. Her serial beta-hCG results are: Week 2 post-evacuation: 42,000; Week 6: 18,000; Week 10: 14,200; Week 14: 14,500; Week 18: 13,900 mIU/mL. She has been compliant with OCP. She reports no symptoms. Chest X-ray shows two small pulmonary nodules. Pelvic ultrasound shows a 2.1 cm right uterine wall lesion with increased vascularity.

DISCUSSION POINTS

  • Interpret the hCG surveillance curve. Does this pattern meet the FIGO diagnostic criteria for gestational trophoblastic neoplasia? Which criterion applies here?
  • With the pulmonary nodules and uterine lesion, what is the likely histological diagnosis (invasive mole vs choriocarcinoma vs placental site trophoblastic tumour)? How would you investigate further to classify and stage this GTN?
  • Explain the WHO prognostic scoring system for GTN (low-risk vs high-risk). What information do you need to calculate Mrs Kamala's score? What are the chemotherapy implications of low-risk vs high-risk GTN?
  • Mrs Kamala is deeply distressed and asks if she has cancer. How would you counsel her about the curability of GTN, including in metastatic disease?
Click to reveal Trigger 5: Synthesis — Systems Thinking and Patient Safety (discuss previous trigger first!)

Trigger 5: Synthesis — Systems Thinking and Patient Safety

The obstetric team conducts a structured case review. They note that Mrs Kamala was initially assessed at the PHC three weeks earlier with 'heavy vomiting and a uterus large for dates' and was sent home with an anti-emetic prescription. The PHC doctor had documented: 'Possible threatened abortion — uterus slightly large, closed os. Advised pelvic rest.' The reason for the large uterus was not investigated further at that visit.

DISCUSSION POINTS

  • What clinical red flags at the PHC visit should have triggered further investigation? List at least four features that, if recognised, would have prompted an earlier ultrasound referral.
  • How could the passage of grape-like vesicles have been elicited in the history at the PHC, and what does this symptom specifically indicate? Why is it pathognomonic?
  • Design a simple two-question clinical screening tool that a PHC doctor without ultrasound could use to identify patients at 10-14 weeks who need urgent obstetric referral for suspected molar pregnancy.
  • Reflect on the system-level factors (workload, equipment, training) that contributed to the delayed diagnosis at the PHC level, and suggest one realistic, low-cost intervention that could reduce diagnostic delay for molar pregnancy in resource-limited settings.

Group Task Assignments

  • Before Trigger 1: Each student writes a differential diagnosis for 'uterus large for dates at 14 weeks with heavy vomiting' — share and compare lists before opening Trigger 1.
  • After Trigger 2: Divide the group into two sub-groups — one argues FOR intraoperative oxytocin during molar evacuation, one AGAINST. Present arguments and reach a consensus.
  • After Trigger 3: Construct a written patient discharge summary and follow-up plan for Mrs Kamala that a PHC doctor could use to conduct her beta-hCG surveillance over the next 6 months.
  • After Trigger 4: Using the WHO prognostic scoring criteria, score Mrs Kamala's GTN. Decide whether she qualifies for single-agent or multi-agent chemotherapy. Present to the tutor.
  • After Trigger 5: As a group, draft a one-page clinical decision aid poster for PHC staff titled 'When to suspect molar pregnancy' — include the 4 red flags, the grape-like vesicle symptom, and the referral action.

Learning Issues

Research these questions and bring your findings to the discussion.

  1. [OG9.5] What are the pathological, clinical, and biochemical differences between a complete and a partial hydatidiform mole, and how does this distinction affect the risk of gestational trophoblastic neoplasia?
  2. [OG9.5] What are the FIGO criteria for diagnosing gestational trophoblastic neoplasia after molar evacuation, and what does the WHO prognostic scoring system determine about treatment choice?
  3. [OG9.6] What is the molecular mechanism by which extreme beta-hCG levels cause gestational thyrotoxicosis, and how is this managed differently from primary hyperthyroidism in pregnancy?
  4. [OG9.5] Why is suction curettage preferred over sharp curettage for molar evacuation, and what are the specific complications that must be anticipated and prevented?
  5. [OG9.1] How should a PHC-level clinician differentiate between molar pregnancy and other causes of uterus large for dates at 12-14 weeks without access to ultrasound?