Preeclampsia is a heterogeneous syndrome thought to complicate 5
to 8% of pregnancies.1 At term, the disease is easily managed by
delivery of the fetus, although preterm severe disease can present a
diagnostic and therapeutic challenge.2,3 It is well-established that
women with twin pregnancies are at increased risk of hypertensive
disorders in pregnancy,4–9 however, prior studies have attributed a
risk to the entirety of gestation, rather than assessing when rates of
disease begin to increase. Thus it is unknown whether twin
pregnancies are affected by preeclampsia earlier than are