The goal of this observational study is to define the predictive value of intrauterine fetal death for different longitudinal patterns of uterine artery Doppler indices (UtA-PI, UtA-RI and notch) from the second and third trimester of pregnancy in patients admitted with a diagnosis of intrauterine foetal death in the period January 2010-April 2020.

No changes in the obstetrical conduct of patients with MEFs are expected, since the data will be analysed retrospectively in patients in whom the event of intrauterine foetal death has already occurred. Patients will be treated according to normal clinical protocols.

The following information will be recorded for each patient

• Age

• Body mass index (BMI)

• Ethnicity

• Parity

• Method of pregnancy onset (spontaneous vs. medically assisted procreation)

• Maternal pathologies (if any)

• Any foetal pathologies

• Ultrasound parameters in the second and third trimester of pregnancy

  • Estimation of fetal weight
  • Umbilical artery Doppler (UA-PI)
  • Uterine artery Doppler (UtA-PI, UtA-RI and notch)

• Gestational age of fetal endouterine death

• Type of delivery

• Newborn and placental weight

• Histopathological findings of newborn and annexes (placenta and umbilical cord)

Inclusion Criteria:

• Fetal endouterine death in single pregnancies with gestation period ≥ 24 weeks
• Obtaining informed consent form

Exclusion Criteria:

• Multiple pregnancies

Assuming a standard deviation of 0.5 in the Doppler values of both cases and controls and a difference in the intercepts of 30% of the two regression lines, it is estimated that 72 cases and 4791 controls are needed to obtain a power of 80% at a type I error of 5%. The controls will be represented by the Doppler values reported in the literature for pregnancies not complicated by MEF.