Pregnancies achieved by assisted reproductive technology (ART) are associated with a spontaneous miscarriage (SAB) rate as high as a 10–25% even after documentation of fetal cardiac activity. Our objective was to determine which ultrasound parameters are relevant in predicting miscarriage after documentation of fetal viability following ART.METHODS:
A retrospective chart review was performed at Wayne State University and its affiliated infertility clinic to assess factors such as such fetal heart rate (FHR), sac size (SAC), and crown rump length (CRL). All 104 ART cycles between 2008 and 2011 resulting in singleton clinical pregnancy were analyzed. The four visits following a positive pregnancy test were analyzed for FHR, SAC and CRL.RESULTS:
The relationship between the minimum (min) values of FHR, SAC, and CRL recorded at each visit between 6 and 9 weeks gestation and SAB were examined using Pearson/Spearman correlations, logistic regressions, and receiver-operating characteristic (ROC) curves. FHR_min, SAC_min, and CRL_min were positively correlated with each other (P<.05) and each was negatively correlated with SAB (P<.05). Regression analyses revealed that maternal age and CRL_min were not significant predictors for SAB unlike FHR_min and SAC_min. With one unit increase in FHR_min and SAC_min, the odds of SAB were reduced by 4% and 22%, respectively.CONCLUSION:
FHR and SAC can be useful in predicting miscarriage after ART. There is a decrease in miscarriage rates as minimum FHR and minimum sac size increase. Further studies need to be conducted to determine which other parameters can predict a decrease risk of SAB.