Reducing early pregnancy loss with vitamin D3: an analysis of serum 1,25-(OH)D3 modulation and miscarriage risk

Abstract

This case-control study of 124 early-pregnant women found that daily supplementation with 400 IU of vitamin D₃ significantly increased serum 1,25-(OH)D₃ levels and was associated with a lower incidence of threatened miscarriage. The study suggests that vitamin D₃ supplementation could reduce the risk of early miscarriage and improve pregnancy outcomes by modulating immune responses and hormonal stability.

Keywords: early pregnancy loss; immune modulation; miscarriage prevention; serum 1,25-(OH)D3; vitamin D3 supplementation.

Fig. 1.

Inclusion and exclusion process flowchart.

Fig. 2.

Dynamic changes in serum 1,25-(OH)D₃ concentration in patients from the experimental and control groups. Represents the time points on the x-axis, and the serum 1,25-(OH)D₃ concentration (ng/ml) on the y-axis. Statistical significance: There was no statistically significant difference between the two groups at the initial visit and on the 7th day (p>0.05). However, there was a statistically significant difference between the two groups on the 14th and 21st days (p<0.05).

Fig. 3.

Residual scatter plot for the model diagnosis of serum 1,25-(OH)D₃ concentration.

Fig. 4.

Dynamic changes in serum HCG and P concentrations in patients from the experimental and control groups. (A) The horizontal axis represents time points, and the vertical axis represents serum HCG concentration (ng/ml). The sample sizes for the experimental and control groups were both 50. The statistical analysis revealed the following results: there were no statistically significant differences between the two groups at the initial visit and on the 7th day (p>0.05). However, on the 14th and 21st days, the experimental group showed a significant increase compared to the control group, with statistically significant differences observed (p<0.05). (B) The horizontal axis represents time points, while the vertical axis represents serum P concentration (ng/ml). The sample sizes for the experimental and control groups were both 50. The statistical analysis showed no significant differences between the two groups at the initial visit, 7th day, 14th day, and 21st day (p>0.05).

Fig. 5.

Dynamic changes in serum cytokine concentrations in patients in the experimental and control groups. (A) Axis X represents the time points, and Axis Y represents the serum TNF-α concentration (ng/ml). The sample sizes of the experimental and control groups were both 50. Statistical analysis results are as follows: at the initial visit and on the 7th and 14th days, there were no statistically significant differences between the two groups (p>0.05). However, on the 21st day, the experimental group showed a decrease compared to the control group, indicating a statistically significant difference (p<0.05). (B) Axis X represents the time points, and Axis Y represents the serum IL-4 concentration (ng/ml). The sample sizes of the experimental and control groups were both 50. Statistical analysis results showed no statistically significant differences between the two groups at the initial visit and on the 7th, 14th, and 21st days (p>0.05). (C) Axis X represents the time points, and Axis Y represents the serum IL-10 concentration (ng/ml). The sample sizes of the experimental and control groups were both 50. Statistical analysis results indicated no statistically significant differences between the two groups at the initial visit and on the 7th day (p>0.05). However, on the 14th and 21st days, the experimental group showed an increase compared to the control group, with statistically significant differences (p<0.05). (D) Axis X represents the time points, and Axis Y represents the serum IL-2 concentration (ng/ml). The sample sizes of the experimental and control groups were both 50. Statistical analysis results demonstrated no statistically significant differences between the two groups at the initial visit and on the 7th day (p>0.05). However, on the 14th and 21st days, the experimental group showed a decrease compared to the control group, indicating statistically significant differences (p<0.05).

Fig. 6.

Model diagnosis—residual scatter plots. (A) Scatter plot of residual serum TNF-α concentrations. (B) Scatter plot of residual serum IL-4 concentrations. (C) Scatter plot of residual serum IL-10 concentrations. (D) Scatter plot of residual serum IL-2 concentrations.

Fig. 7.

Literature screening process and quality assessment of included studies. (A) Flowchart of literature inclusion. (B) Summary of bias risk assessment in included studies.

Fig. 8.

Meta-analysis forest plot of the association between serum 1,25-(OH)D₃ concentration and early miscarriage.

Fig. 9.

Sensitivity analysis forest plot of the relationship between serum 1,25-(OH)D₃ levels and the risk of early miscarriage.

Fig. 10.

Results of publication bias test in meta-analysis.

Fig. 11.

The role of vitamin D₃ supplementation in reducing the risk of early pregnancy miscarriage.