P–594 Ovarian stimulation with luteinizing hormone supplementation: the impact of timing on ovarian response and ICSI outcomes
Authors: Iaconell A , Setti A , Braga D , Borge E 
Published: August 2021

Abstract

Study question
Is there an impact of recombinant luteinizing-hormone (rLH) administration timing during controlled ovarian stimulation (COS) on ovarian response and intracytoplasmic sperm injection (ICSI) cycles outcomes?

Summary answer
rLH supplementation in patients with poor ovarian response (POR) improves laboratorial and clinical outcomes when started in the mid-follicular phase, in GnRH antagonist ICSI cycles.

What is known already
Meta-analyses demonstrated that the use of rLH combined with rFSH for COS may lead to more ongoing pregnancies than rFSH alone. However, there is limited evidence that the timing of rLH addition to rFSH may impact the ovarian response or the outcomes of ICSI, based on a limited casuistic, which demonstrated improved ovarian response, embryo quality and pregnancy rate with LH supplementation from GnRH antagonist administration day, in estimated POR patients. The objective of the present study was to further investigate this hypothesis in a larger population, and in subpopulations of patients stratified by age and response to COS.

Study design, size, duration
This historical cohort study included data obtained via chart review of 1278 ICSI cycles performed in 1278 patients between 2015 and 2018, in a private university-affiliated in vitro fertilization center. Post hoc power analysis was calculated, given α of 5%, sample size of 1278, and effect size for implantation rate. The achieved power was superior to 99%.

Participants/materials, setting, methods
Two groups were formed according to timing of LH administration: Group LH-start (n = 323), in which LH was started on day–1; and Group LH-mid (n = 955), in which LH was started with GnRH antagonist. Then, data were stratified according to female age (&lt;35 years-old, n = 283, and ≥35 years-old, n = 995) and response to COS (poor response (POR): ≤4 retrieved oocytes, n = 423, and normal response: &gt;5 retrieved oocytes, n = 855). Ovarian response and ICSI outcomes were compared among the groups.

Main results and the role of chance
In POR patients, significantly higher fertilization rate (68.3% ± 2.5 vs. 78.6% ± 3.7, p = 0.023), blastocyst development rate (22.5% ± 7.2 vs. 44.7% ± 6.2, p = 0.022) and implantation rate (17.6% ± 59.1 vs. 20.2% ± 43.2, p &lt; 0.001) were observed in Group LH-mid, even though the amount of LH used in these patients was not significant different from that used in Group LH-mid from patients with normal response to COS (1062.35 IU ± 54.33 vs. 925.81 IU ± 414.41, p: 0.431, respectively). For the general group and in patients aged ≥ 35 years, higher blastocyst development rates were observed in Group LH-mid compared to Group LH-start (33.0% ± 31.9 vs. 40.8% ± 32.6, p = 0.012, and 28.8% ± 30.4 vs 38.5% ± 32.3, p = 0.006, respectively). In patients aged &lt; 35 years and in those with normal response to COS, similar outcomes were obtained irrespective of timing of LH administration.

Limitations, reasons for caution
The limitations included the retrospective design and limited sample size in subpopulations. In addition, the reduced clinical outcomes related to POR patients may hamper the true estimation of the differences between the stimulation groups in terms of pregnancy and miscarriage rates.
Wider implications of the findings: In POR patients, mid-follicular phase LH supplementation starting with 150 IU daily doses, may rescue the ongoing cycle by compensating an initial slow response, and balancing the deprivation of endogenous LH in GnRH antagonist cycles, with no need of expending more gonadotropin compared to patients with normal response to COS.

Trial registration number
Not applicable