In normal-weight patients, numerous studies show an equivalence of efficacy between dinoprostone and balloon to induce labor. In obese patients, this efficacy is not known, although inductions of labor are more frequent. MODOBAT aims to describe the ability to obtain a vaginal delivery of two modality of induction of labor (vaginal dinoprostone and single balloon Foley catheter) in obese women at term.

Obesity has for several decades become a global epidemic in developed countries. In case of pregnancy, obesity leads to an increased risk of obstetric complications, the indications of induction of labor are then more frequent. Unfortunately the rate of failed induction is also higher and therefore the risk of caesarean section is increased in obese women compared to normal-weight patients when induction of labor is indicated. However, in this context effectiveness of each mode of induction is not known. Some retrospective studies would suggest that the balloon would be more effective because it would not be affected by the increase in fat mass but this result are not , but the to confirm this hypothesis.

The aim of this study is to describe the caesarean section rate in induction of labor by vaginal dinoprostone and single balloon Foley catheter in obese women. Patients in the vaginal dinoprostone arm will be included retrospectively and patients in the single balloon Foley catheter arm will be included prospectively.

Inclusion Criteria:

• Age ≥ 18 years
• Medical indication of induction of labor
• BMI ≥ 30 kg / m2
• Bishop < 6
• Singleton
• Gestational age > 36 SA + 6j
• Cephalic presentation

Exclusion Criteria:

• Adults under guardianship or curatorship
• Scarred uterus
• Placenta praevia

Patients of the level III maternity of university hospital center of Besançon and level IIB maternity of regional hospital of Trevenans, France.