According to the GTG 43 - A discussion should take place with women regarding induction of labour after 37+0 weeks of gestation.
The case for intervention (after 37+0 weeks of
gestation) may be stronger in those with more severe biochemical abnormality (transaminases and bile acids).

A large study based on historical data suggests that immediate delivery at 36 weeks of gestation without fetal lung maturity testing or steroids was optimal . ( The Obstetrician & Gynaecologist 2016;18:273–81. DOI: 10.1111/tog.12308) .
To answer this question prospective testing in a randomised controlled trial is required.

Where the prothrombin time is prolonged, the use of
water-soluble vitamin K (menadiol sodium phosphate) in doses of 5–10 mg daily is indicated( usual dose is 10 mg daily). Fat soluble Vitamin K ( like the preparation in injection) will be absorbed poorly in Cholestasis.
There is no specific evidence to support or refute this practice, and the data regarding the risk of intrapartum or postpartum haemorrhage are limited.

Where Prothrombin time is normal, there may still be benefit by way of reduction of PPH risk ( 12 % PPH in women who took oral vitamin K versus 45% in women who did not take) .
However the British National Formulary( BNF) , based on 1955 data, recommends against use of Vitamin K in late pregnancy and labor because of risk of haemolytic anaemia, hyperbilirubinaemia and kernicterus in the newborn- This data likely needs revision, and many hospitals do not follow this advice by the BNF.

Postnatal vitamin K must be offered to the babies in the usual way.