Regarding transmission of HIV to infant from infected HIV mother, which statement is/are true:

Zidovudine is given IV Infusion staing at onset of labour or4 hours prior to CSsection,Loading dose is 2mg/kg/hr and maintainance dose is 1mg/kg/hr Transplacental transmission occurs :20% before 36 weeks,50% before delivery,30% during labour Breast feeding doubles risk of MTCT but alternative forms of infant nutrition are not safe. D.C.DUTTA'S TEXTBOOK OF OBSTETRICS,Pg no:283,9th edition