Iron status linked to recurrent miscarriage in women

Women with recurrent pregnancy loss (RPL) appear to have markedly lower serum ferritin levels compared with those who have no known fertility problem, suggesting that iron status is associated with the severity of reproductive disturbance in women with RPL, according to a study.

The analysis included 84 women referred to the RPL Unit and 153 women of reproductive age with no known fertility problem. Compared with controls, women with RPL were more likely to be older (median, 35 vs 33 years; p=0.005) and have a higher body mass index (median, 23.4 vs 21.7 kg/m²; p=0.003).

Serum ferritin levels, measured prior to pregnancy attempt, were significantly lower in the RPL than in the control group (median, 39.9 vs 62.2 µg/L; p=0001). More women in the RPL group had iron deficiency (serum ferritin <15 µg/L; 10.7 percent vs 4.5 percent; p=0.072).

Multivariable logistic regression analysis revealed that RPL was associated with fivefold odds of having low serum ferritin levels (<30 µg/L; adjusted odds ratio [aOR], 5.16, 95 percent confidence interval [CI], 2.43–10.95; p<0.001).

Serum ferritin concentration was inversely related to the number of previous pregnancy losses, with median concentrations being 55.30 µg/L among women with two or three losses, 40.35 µg/L among those with four losses, and 25.60 µg/L among those with four or more losses (p=0.010).

The present study, however, was not able to establish a causal relationship between serum ferritin levels and RPL, so it was unclear whether iron depletion was a risk factor for experiencing pregnancy loss or a result of consecutive losses.

More studies are needed to confirm the findings and assess if iron supplements can increase the chance of live birth in women with RPL.