RESUMEN
OBJECTIVE: The purpose of this study was to determine whether fetal heart rate (FHR) can be used to date pregnancies in the early first trimester using the gold standard of crown-rump length (CRL) dating as a reference. METHODS: This single center study evaluated women undergoing obstetrical ultrasounds between 4.5 and 8.5 weeks. FHR and gestational age (GA) based on CRL were obtained. Linear regression analysis and a Bland-Altman plot were used to demonstrate the relationship between the two measurements. A further simplified version of the relationship between CRL and FHR that may be clinically useful was calculated. RESULTS: 176 patients were included in the study. The Pearson correlation coefficient was 0.95, indicating a strong correlation between the two dating methods. The Bland-Altman plot demonstrated agreement across GA tested. A simple arithmetic formula of GA(weeks)=FHR (beats per minute)/20 was calculated. 169/176 patients had <4 days discrepancy between FHR- and CRL-based dating using this formula. CONCLUSION: We found that a simple formula based on FHR may accurately date early pregnancies. This method, if further validated, may represent an important tool for pregnancy dating.
Asunto(s)
Largo Cráneo-Cadera , Edad Gestacional , Frecuencia Cardíaca Fetal , Ultrasonografía Prenatal , Femenino , Humanos , Embarazo , Primer Trimestre del EmbarazoRESUMEN
Currently, in common practice, no pain control is provided to the patient undergoing transvaginal chorionic villus sampling (CVS). Chorionic villus sampling is an invasive procedure involving an 18-gauge needle stick through the abdomen or passage of a suction catheter through the cervix. Furthermore, CVS is a mechanically difficult procedure for the clinician and requires considerable skill and training. There have been prior studies establishing the efficacy of using a topical anesthetic in similar gynecologic procedures. We share our method of performing CVS, which aids in pain relief for the patient and concurrently aids the practitioner in executing this precise procedure.