Dados do Trabalho

Title

Effect of body mass index on blastocyst morphokinetics in polycystic ovary syndrome (PCOS): a time-lapse analysis of embryos obtained after progestin primed ovarian stimulation cycles

Objective

To demonstrate if there are differences in blastocyst morphokinetics between normal weight and overweight/obese women with PCOS after controlled ovary hyperstimulation with progestin primed ovarian stimulation (PPOS) protocol.

Methods

PCOS is a common endocrine disorder associated with overweight and obesity in women of reproductive age. An increasing number of PCOS women are seeking for assisted reproduction techniques (ART) and the impact of overweight and obesity on the reproductive outcome of PCOS women who undergo IVF/ICSI have yielded conflicting results.
PCOS obese women require higher doses of gonadotropin for a longer duration to achieve ovarian hyperstimulation, and overweight and obesity are associated with higher miscarriage rate in IVF/ICSI patients. However, the effect of overweight and obesity in PCOS on the morphokinetics parameters of blastocysts is yet to be determined.
This was a retrospective cohort study on blastocyst morphokinetics from February/2021 and January/2022, in a single ART center. One-hundred twenty-three blastocysts from 24 PCOS patients submitted to PPOS protocol were included and classified into three groups: normal weight (n=86), overweight (n=20) and obese (n=17), according to the World Health Organization (WHO) classification. There were no underweight women in this cohort. Embryos from patients with endometriosis, previous ovarian surgerydiabetes, autoimmune diseases and male factor were excluded from this analysis. Embryos were cultured in Embryoscope Plus incubator and classified according to KIDScore (Vitrolife) morphokinetic-based algorithm in good (7.0-9.9), fair (4.0-6.9) and poor quality (1.0-3.9). We performed two-by-two comparisons between the average scores obtained from the quality of the embryos fornormal x overweight; normal x obese; overweight x obese and normal x overweight + obese groups.

Results

The normal and obese groups had a mean age statistically higher than the overweight group (36.7 ± 4.0; 38.5 ± 2.7 and 33.2 ± 2.8 respectively, p<0.0001). The number of oocytes retrieved was significantly higher in the normal weight and overweight groups (20.0 ± 7.3 and 22.3 ± 8.1), when compared to the obese group (10.6 ± 5.0, p<0.0001). As for the blastocyst formation rate, the normal and overweight groups had rates statistically higher than those in the obese group (0.6 ± 0.2; 0.6 ± 0.1 and 0.5 ± 0.2, p=0.0114).
The embryos generated by patients in the normal BMI group had a mean score of 6.3 (± 1.8); the overweight group had a mean score of 6.1 (± 1.9) and the obese group had a mean score of 7,0 (± 1.71). There was no significant difference in relation to the average quality score obtained between the three groups analyzed (p>0.05), according to the Tukey Test for multiple comparisons. In the analyzes two by two (normal x overweight; normal x obese; overweight x obese and normal x overweight + obese groups), there was also no statistical significance (p>0.05), according to the unpaired T test.Limitations, reasons for caution:
We found no relation between BMI and embryo morphokinetics scores, despite the obese group having higher mean age.

Conclusion

Many studies have shown a detrimental effect of obesity on IVF/ICSI and obstetrics outcomes in PCOS women, but a few have focused on the embryo quality. Our study found no relation between BMI and embryo morphokinetics scores in PCOS women who underwent PPOS IVF/ICSI cycles.

Keywords

body mass index, in vitro fertilization, polycystic ovary syndrome, embryo morphokinetics, time-lapse monitoring