Effect of trigger day serum luteinising hormone levels on the in-vitro fertilization outcome: an observational study

Controlled ovarian stimulation leads to profound changes in the endocrine characteristics of the ovarian cycle. Serum luteinising hormone (LH) levels on the day of trigger have been shown to correlate with oocyte quality and pregnancy rate in antagonist cycles.

This is an observational study of 86 women undergoing an antagonist in-vitro fertilisation cycle. Oocyte maturation trigger used was either Inj. human chorionic gonadotropin or Inj. triptorelin 0.2 mg s/c or a combination of both. Women were categorised into four groups based on serum LH levels on the day of trigger i.e., LH ≤0.5 (n=8), LH=0.6- 1.0 international units (IU)/L (n=12), LH=1.0-1.5 IU/L (n=13), and LH >1.6 IU/L (n=53) and the subgroup analysis was done based on type of trigger used.

Mature oocyte (MII) retrieval rate did not show a significant relation with serum LH levels (87%, 89%, 77%, and 76% in groups with LH <0.5, 0.5-1.0, 1.0-1.5, and >1.5 IU/L respectively; P-value=0.243). There was no significant difference in the clinical pregnancy rate either when women were split according to the type of trigger given or according to trigger day LH levels. Women with low LH levels (<0.5 IU/L) required significantly more doses of gonadotropins compared to women with LH levels of 1.0-1.5 IU/L. (3,531+1,133 vs. 2,281+938; P-value=0.01).

Based on the observation from the current study, there was no significant association of serum LH levels with MII retrieval rate and clinical pregnancy rate. The group with low LH levels required slightly longer days of stimulation.