3-dimensional endometrial volume as a predictor of pregnancy in in-vitro fertilisation cycles over 2-dimensional endometrial thickness

Abstract

OBJECTIVE: To evaluate the role of endometrial volume as predictor of pregnancy in In Vitro Fertilisation Cycles (IVF) over endometrial thickness. DESIGN: Prospective, non randomised clinical study. MATERIALS AND METHODS: This was a prospective observational study. A total of 100 infertile women were recruited from our IVF-Embryo transfer program from Feb to March 2014. Endometrial volume was measured on the day of hCG using the VOCAL (Virtual Organ Computeraided AnaLysis) imaging program integrated into Volusen E8 ultrasound system. RESULTS: The mean age was 31.5 years and the mean duration of infertility was 6 years. The mean endometrial thickness was 9.7 mm and the mean endometrial volumewas 4.6 cm3. Overall 31(31%) patients conceived and in these women the endometrial volumewas between 3-8 cm3. All patients who conceived had thickness more than 7 mm. 38 (38%) patients had thickness >7 mm but endometrial volume< 4 cm3 and did not conceive. The positive predictive value of endometrial volume for conception was 40% with sensitivity as high as 93.5%. Endometrial thickness had a high negative predictive value of 68.3% with 97% specificity. Among those who conceived 16 (51%) patients had blood flow in Zone 3, 14 (45%) patients had flow in Zone 2 and only one had flow in Zone 1. CONCLUSION: With a thin endometrium and low endometrial volume, the probability of conception is very low in an in-vitro fertilisation/ embryo transfer cycle and cryopreservation should be recommended. Endometrial thickness more than 7 mm and volume more than 3cm3 together increase the probability of pregnancymore than thickness alone as volume is an objective measure of implantation potential of endometrium. However furthur study is needed for definitive conclusion.