Limitations of current definitions of miscarriage using mean gestational sac diameter and crown–rump length measurements: a multicenter observational study

Abstract

Objectives There is significant variation in cut-off values for mean gestational sac diameter (MSD) and embryo crown-rump length (CRL) used to define miscarriage

Misoprostol treatment vs expectant management in women with early non‐viable pregnancy and vaginal bleeding: a pragmatic randomized controlled trial

“…Because of new recommendations for ultrasound criteria of early pregnancy failure [5][6][7] , we changed our ultrasound criteria of non-viability in 2014. Before 2014 the criteria of non-viability in our study were one of the following: (1) intrauterine gestational sac with a mean diameter > 16 mm with no embryonic pole 20 or (2) a gestational sac with an embryo with CRL ≥ 5 mm without cardiac pulsations 20 , or (3) if the above criteria were not fulfilled, a gestational sac with or without an embryo that showed no significant development at a repeat scan after 7 days 20 .…”

“…Before 2014 the criteria of non-viability in our study were one of the following: (1) intrauterine gestational sac with a mean diameter > 16 mm with no embryonic pole 20 or (2) a gestational sac with an embryo with CRL ≥ 5 mm without cardiac pulsations 20 , or (3) if the above criteria were not fulfilled, a gestational sac with or without an embryo that showed no significant development at a repeat scan after 7 days 20 . After April 2014 the non-viability criteria in our study were one of the following: (1) intrauterine gestational sac with a mean diameter ≥ 25 mm with no embryonic pole or (2) a gestational sac with an embryo with CRL ≥ 7 mm without cardiac pulsations, or (3) if the above criteria were not fulfilled, a gestational sac with or without an embryo that showed no significant development at a repeat scan after 7 days 5,6,8,9 . Since all patients were managed as outpatients we did not include patients with a fetus with CRL > 33 mm because of the risk of heavy bleeding at expulsion of the pregnancy.…”

Ultrasonographic evaluation of first trimester bleeding per vaginum

“…More recent data, particularly when considering measurement variability, have suggested that a failed intrauterine pregnancy should be diagnosed only when cardiac activity is absent in an embryo ≥7 mm, using trans-vaginal US. 2 Bilateral adnexa were scanned to rule out ectopic gestation and other pathology.…”

Rationalising the change in defining non‐viability in the first trimester

“…studied over one thousand pregnancies diagnosed as IPUV across four different hospitals in a multicentred prospective trial 10 . The end point was ongoing pregnancies at the 11–14 week scan.…”

“…It had been previously thought that in a normal pregnancy, the CRL should increase by approximately 1 mm per day between 7 and 12 weeks 11 23 In the fourth paper discussed here, Abdallah at el looked at a subset of the 1060 pregnancies from their main study 10 11 A total of 359 pregnancies were analysed.…”