"The study did n't address causes , and only noted the correlation , but the lead doctor did speculate that it may have something to do with hormonal changes that need to run to completion ."
"How strange that so much depends on the first pregnancy , and not the others ."
"doctor did speculate that it may have something to do with hormonal changes that need to run to completion ."
"much depends on the first pregnancy , and not the others"