Difference between mean gestational sac diameter and crown-rump length as a marker of first-trimester pregnancy loss after in vitro fertilization

There is a strong inverse relationship between mGSD − CRL and first-trimester pregnancy loss in IVF patients, although the incidence of pregnancy loss with a mGSD − CRL <5 mm was significantly lower than previously reported. Small mGSD − CRL was not associated with an increased risk of complications in pregnancies that continued beyond 20 weeks. The association between mGSD, CRL, and miscarriage is complex.