Evaluation of ovulation by urinary LH surge kits versus transvaginal sonography

The study was conducted to evaluate the efficacy of urinary LH surge kits and transvaginal ultrasonography (TVS) to detect ovulation in induced cycles and to compare the ovulation rates by both methods. Prospective observational cohort study on 144 women with anovulatory infertility aged 18-35 years, fulfilling the inclusion criteria were given letrozole for ovulation induction. All were randomly divided into two groups. Group 1 women were asked to check ovulation by urinary LH surge kits and group 2 women were called for follicle monitoring by TVS. Letrozole has no negative effect on the endometrium; the induced cycle has a larger diameter of follicle (median: 22 mm). In the induced cycle ovulation occurs later compared to normal cycle (D-16) and half of the women had a BMI more than the recommended WHO criteria (average was 25.28 kg/m2). Number of letrozole cycles (p=0.2642), dose requirement (p=0.0812) and pregnancy rates (10.26% versus 18.19%) were comparable in both groups. TVS is objective, accurate, and thus a standard modality for ovulation detection. LH surge kit is subjective, having more chances of error but can be used as a good alternative in certain settings like women from the remote area, and women having fear of invasive modality.