Multiple Pregnancy

A 28-year-old primigravida from Delhi presents at 18 weeks of gestation with vaginal spotting and mild lower abdominal pain. Ultrasound reveals a dichorionic diamniotic twin pregnancy with a live fetus in each sac. However, one twin shows an empty gestational sac with no yolk sac or fetal pole. The patient is hemodynamically stable and has no fever. What is the most appropriate management at this stage?

A 32-year-old woman with a monochorionic diamniotic twin pregnancy is seen at 24 weeks for routine antenatal care. Ultrasound shows Twin A with an estimated fetal weight of 650 g and Twin B with 580 g. Doppler studies reveal absent end-diastolic velocity (AEDV) in the umbilical artery of Twin B, with normal Doppler in Twin A. The patient is asymptomatic with normal blood pressure and no proteinuria. What is the most appropriate next step in management?

In monozygotic twin pregnancies, what is the most common type of placentation?

Which complication is unique to monochorionic twin pregnancies and results from unequal blood flow between twins?

A 28-year-old primigravida from Delhi presents to the antenatal clinic at 16 weeks of gestation with complaints of excessive nausea and vomiting for the past 3 weeks. On examination, the uterus is enlarged more than expected for gestational age. Serum β-hCG is markedly elevated at 450,000 mIU/mL (normal for 16 weeks: 25,000–288,000 mIU/mL). Transvaginal ultrasound reveals two gestational sacs with fetal poles. What is the most likely diagnosis, and what is the primary obstetric concern in this pregnancy?