Background: Many studies on the prognostic significance of the Yolk sac for the pregnancy outcome have been performed with conventional sonography and more recently with TVS. The results are conflicting. This prospective co relational study is conducted to assess the correlation of first trimester pregnancy outcome using yolk sac measurements and embryonic heart rate.

Material & Methods: A Hospital based prospective study done on 100 pregnant women between 6-9 weeks of gestation who were attending the antenatal clinic in Department of Obstetrics and Gynaecology, Mahatma Gandhi Hospital, Bhilwara, Rajasthan. Follow up scan: was done every two weeks where (gestational sac diameter, yolk sac diameter, crown rump length and fetal heart rate) were measured every time until the pregnancy reached 12 weeks.

Results: The Yolk sac size varied between 2.5 to 7.0 with a mean of 4.892 mm. The Yolk sac size has significant correlation with the first trimester pregnancy outcome. (T-test p=0.002**). The heart rate of the fetus predicted the first trimester pregnancy outcome significantly (T-test p=0.048*).

The gestational Age at the time of first scan predicted very significantly the first trimester pregnancy outcome (T-test p<0.001**). The Crown Rump Length (CRL) was ranged between 10 and 58 mm with a mean of 24.51 mm. The CRL has significant predictive value in first trimester pregnancy outcome (T-test p=0.044*).

Conclusion: We concluded that yolk sac size and the embryonic heart rate is a reliable, cost effective and beneficial in predicting first trimester pregnancy outcome especially in patients who conceive following IVF.

Keywords: First trimester pregnancy, Yolk sac size, Crown rump length, Gestational age, Heart rate.

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Dr Sapna Aseri

MS (Obst & gynae), Senior Resident, Department of Obs & Gynaecology

RVRS Medical College & Attached groups of Mahatma Gandhi Hospital, Bhilwara, Raj, India