All patients will be subjected to the following:

1-Umbilical cord milking or delayed cord clamping according to the ranamization table 2 serial measurement of cerebral tissue oxygenation 3- serial echocardiography for ductus arteriosus (DA)functional closure

• Study Population: neonates born and admitted to Ain shams university neonatal intensive care units (NICUs).

  • Inclusion criteria:

    o Preterm infants with gestational age (GA) of 28 - 34 weeks born and admitted to Ain shams university NICUs.

  • Exclusion criteria:

    • Late preterm with gestational age 34-37 weeks.
    • Term infants with gestational age > 37 weeks.
    • NIRS data that was not obtained within 1st hour after birth.
    • Congenital heart disease (other than DA or small atrial septal defects/patent foramen oval/ventriculi septal defects).
    • Hypoxic-ischemic insult.
    • Major congenital deformations. #All participants will be subjected to the following:

• Infants will be considered to be randomized at the time of enrolment for:

  o Delayed cord clamping (DCC) and Umbilical cord milking (UCM)

• Near-infrared spectroscopy (NIRS):

  • In the delivery room: after the intervention (UCM or DCC) the regional cerebral tissue oxygenation (rScO2 ) and cerebral fractional tissue oxygen extraction (c FTOE) will be collected for 10 minutes within 1st hour after birth.
  • In the neonatal intensive care unit: NIRS data will be collected for 2 hours at 12,24 hours, and 48 hours after birth.

• Echocardiography:

will be performed at 6, 12, 18, 24, and 48 hours of life by using an ultrasound Doppler machine Mindary.M9. assessment of DA functioning closure by measuring duct diameter and direction of blood flow through it.

Inclusion Criteria:

• Preterm infants with gestational age (GA) of 28 - 34 weeks born and admitted to Ain shams university NICUs.

Exclusion Criteria:

• Late preterm with gestational age 35-37 weeks.

  • Term infants with gestational age > 37weeks.
  • NIRS data that not obtained within 1sthour after birth.
  • Congenital heart disease (other than PDA or small atrial septal defects/patent foramen oval/muscularventriculoseptal defects).
  • Hypoxic-ischemic insult.
  • Major congenital deformations.

all involved neonates will be randomized to DCC or UCM according to the randomization table and double-blinded method.