Can vitamin supplements prevent miscarriage during pregnancy? Let's take a look

Abortion usually refers to the termination of pregnancy before 28 weeks of pregnancy and when the fetus weighs less than 1,000 grams. Abortion that occurs before 12 weeks of pregnancy is called "early abortion", and abortion that occurs between 12 weeks and 28 weeks of pregnancy (less than 28 weeks) is called "late abortion". During pregnancy, intrauterine fetal death often occurs in the form of abortion, which ends the pregnancy.

Abortion is a common complication during pregnancy. The incidence of spontaneous abortion accounts for about 15% of all pregnancies, with early abortion being the most common. There are many reasons that can lead to abortion during pregnancy; among them, poor nutrition and insufficient vitamin intake in the diet are related to the increased risk of abortion during pregnancy. Therefore, it is generally believed that supplementing some vitamins in early pregnancy or before pregnancy should help prevent abortion during pregnancy.

So, can vitamin supplementation really reduce the risk of spontaneous abortion during pregnancy? Will vitamin supplementation have adverse effects on pregnancy outcomes (including the fetus, infant and mother)? The results of the study showed:

① Using the fixed-effects model, there was no significant difference in pregnancy outcomes between pregnant women taking any vitamins and the control group, including early or late miscarriage [relative risk (RR) 1.09, 95% confidence interval (CI): 0.95-1.25], stillbirth (RR 0.86, 95% CI: 0.65-1.13), or total fetal damage (RR 1.04, 95% CI: 0.95-1.14).

② Compared with the control group, women who took vitamins before or during the peri-pregnancy period were more likely to have multiple pregnancies (RR was 1.38; 95% CI: 1.12-1.70; 3 studies with a total of 20,986 cases).

Based on the above analysis results, the researchers believe that supplementing any vitamins before or during early pregnancy cannot prevent miscarriage or stillbirth; women who supplement vitamins are more likely to have multiple pregnancies. Whether different combinations of vitamins have an effect on miscarriage, stillbirth or other pregnancy outcomes (including maternal and infant) is not well documented at present, and more clinical data are needed.