Heart rate variability among women undergoing in vitro fertilization treatment: Its predictive ability for pregnancy

This study aimed to assess predictive ability of heart rate variability (HRV) for pregnancy outcomes with in vitro fertilization (IVF) treatment.

A total of 180 women with 261 cycles of IVF and 211 embryo transfers (ETs) were analyzed. HRV was measured at four times during IVF treatment: the first date of menstruation, r-HCG (Ovidrel) administration, and before and after ET. Pregnancy indicators included chemical pregnancy, ongoing pregnancy (> 10 weeks), and live birth (pregnancy > 24 weeks). Mixed effect models were applied to identify predictors for IVF pregnancy. The area under the receiver operating characteristic curve (AUC) was used to assess prediction models for pregnancy.

The HRV values increased during IVF treatment and then decreased after ET. The trend of changes in HRV values during IVF treatment was significant among patients with chemical pregnancy (p < 0.01) and those with live birth (p = 0.02). Women without pregnancy had lower HRV compared to those with IVF pregnancy (p < 0.05). With a one unit increase in HRV difference before and after ET, the odds of chemical pregnancy decreased by 18% (odds ratio; OR: 0.82, 95% CI: 0.70-0.97, p < 0.02). With a one year increase in maternal age, the odds decreased by 16% (OR: 0.84, 95% CI: 0.76-0.93, p < 0.01), 25% (OR: 0.75, 95% CI: 0.58-0.93, p = 0.02), and 28% (OR: 0.72, 95% CI: 0.54-0.91, p = 0.01) for chemical pregnancy, ongoing pregnancy, and live birth, respectively. The AUCs were 0.77 (95% CI: 0.70, 0.84), 0.89 (0.79, 0.98), and 0.91(0.83, 0.99) for the prediction models for chemical pregnancy, ongoing pregnancy, and live birth, respectively.

Reduced HRV may be an indicator for low chance of IVF pregnancy. The changes in HRV before and after ET and maternal age might be prognostic predictors of IVF pregnancy.