P4>1.5懷孕率較低

施打hCG當天，P4>1.5懷孕率比P4<1.5低
(10顆卵子: 30 vs 48%)
(15顆卵子: 35 vs 55%)

http://humrep.oxfordjournals.org/content/25/8/2092.full

Figure 3

Ongoing pregnancy rate according to ovarian response and progesterone levels.