1

Hurley tells Jack 1 of the survivor's blood type is AB negative.

2

Sarah's accident was a little over 2 years before their wedding.

Hurley tells Jack 2 of the survivors' blood type is B positive.

Claire's contractions are coming every 2 minutes.

44

Sarah's pajama shirt had a small 44 on the front and a big 44 on the back. She and Jack play a duet (Heart and Soul) at a piano, which has 88 keys, so they each have 44 keys.
yahof at the fuselage did the math.

60

Kate sends Charlie to fetch Jack when Claire's is appearing to be ready to give birth. Jack tells Charlie, tell Kate to wait until Claire's contractions are 60 seconds apart before having  her push.