**6. Conclusion**

The evaluation of the clinical history of the previous preterm birth and the presence of short cervix (≤25 mm) are the best predictors of preterm delivery in twin pregnancy. Transvaginal ultrasonography for evaluation of the uterine cervix between the 18th and 24th week should be indicated for its cost-effectiveness.

The use of isolated vaginal progesterone in multiple pregnancies with short cervix presents evidence that justifies its use; however, this evidence is to be confirmed by other clinical tests due to the potential bias of the most recent meta-analysis.

Most guidelines do not recommend the use of prophylactic cerclage in patients with short cervix; however, in selected cases of extreme severity, it can be considered.

The use of a cervical pessary does not present solid evidence; however, some studies point out, although with a low level of evidence, that it may be beneficial.

As the low index of complications and the absence of highly efficient intervention in twins justify the utilization of the association of progesterone and cervical pessary, for this author it seems to be better than observing the evolution of the clinical condition.

The use of corticosteroids, between 24th–25th and 34th week, must be indicated in pregnancy in the imminence of delivery or with a high risk of preterm birth and must be avoided in pregnancy with intermediate or low risk, as there are studies which point out undesired effects of this treatment in the short and medium term.

Tocolytics is to be used under the 34th week in order to gain time for carrying out corticosteroids. The first-option drugs in twin pregnancy are the calcium channel blockers.

The use of magnesium sulfate in deliveries under the 32nd week is recommended by the main scientific societies, for the purpose of neuroprotection in twin pregnancy.
