Depending on what lead to IVF failure on the first round, a second attempt could improve the success rate or not.
For instance, if the first IVF cycle failed because of poor uterine receptivity, the protocol will be changed so that it works better on the second attempt.
Usually, various aspects are modified the second time a couple undergoes IVF, something that helps achieve better outcomes in general. It depends, however, on the particularities of each case.
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