Is gestational hypertension beneficial in twin pregnancies?

Objectives: Hypertensive disorders of pregnancy are commonly associated with impaired foetal growth. However, some studies observed that gestational hypertension in twin pregnancy could be beneficial for foetal growth. The aim of this study is to investigate the influence of gestational hypertension on neonatal birth weight among twin pregnancies.

Study design: This is a retrospective study about the comparison of 196 hypertensive twin pregnancies to 912 normotensive ones, who gave birth in the teaching hospital "A. Gemelli" in Rome from 1980 to 2006.

Main outcome measures: Birth weight, inter-twin weight discordance and rate of small for gestational age neonates in the first and second twin.

Results: Birth weight, inter-twin weight discordance and rate of small for gestational age neonates were similar between the two groups. In the normotensive group, the discordance >25% was associated with lower gestational age at the delivery (p<0.00001), data not observed in the hypertensive group. The rate of pregnancies with second twin small for gestational age rose while paralleling the degree of the discordance in both groups.

Conclusion: Gestational hypertension in twin pregnancies, if compared to normotensive ones, is not detrimental for foetal growth.