OBJECTIVE: To determine whether fundal height might predict early delivery in twin pregnancies; that is, whether larger fundal heights predispose to earlier delivery.
METHODS: From the charts of 336 well-dated twin pregnancies, we generated a series of fundal height curves.
RESULTS: Within our population of twin pregnancies, the mean fundal height at any given gestational age did not differ between pregnancies delivered before 34 weeks and those delivered at or after 34 weeks. A single fundal height measurement above the 90th percentile before 34 weeks yielded a sensitivity of 23% and a specificity of 79% for delivery before 34 weeks, with a positive predictive value of 38% and a negative predictive value of 64%.
CONCLUSION: Factors other than uterine overdistention (as measured by fundal height) must be implicated in preterm twin delivery.