Case history / examination
A 38‐year‐old patient, gravida 2, para 1 was referred to our hospital at
9 weeks of gestation following in vitro fertilization. Her past history
included moyamoya disease. Delivery with epidural anaesthesia had been
recommended by the neurosurgeon. Her family history noted that her
father had died of moyamoya disease. At the second trimester screening,
the placenta was attached on the anterior uterine wall. A low‐lying
placenta, succenturiate lobe, and/or multilobed placenta was not
identified. The umbilical cord insertion was marginal. The site of the
umbilical cord insertion was on the lower side of the placenta. Both the
placental position and the site of umbilical cord insertion were above
the upper end of the bladder. At that time, vasa praevia was not
suspected. At 37 weeks of gestation, gestational hypertension occurred.
Elective delivery of the pregnancy was required. Transvaginal ultrasound
without colour doppler did not reveal an abnormal image between the
foetal head and the internal cervical os (Figure 1A). However,
ultrasound with colour doppler was performed in order to exclude for
abnormal insertion of the umbilical cord before introduction of a
transcervical balloon catheter for cervical ripening. A few foetal
vessels were found between the foetal head and the internal cervical os
by using colour and pulse doppler (Figure 1B, 1C).