Guest Author - Carolyn Chambers Clark, RN, EdD

How does vitamin C help protect your baby during pregnancy?

Vitamin C helps build collagen, the glue that holds tissues together in the body, and is important for the health of the amniotic membranes surrounding the fetus that protect it. Inadequate availability of ascorbic acid during pregnancy has been proposed as a risk factor for premature rupture of the chorioamniotic membranes (PROM).

Premature rupture results in a leakage of amniotic fluid from the vagina. This is a normal occurrence during labor, but when it occurs too early in the process, the fetus isn't properly protected and infection can occur, especially if a health care practitioner performs an examination with the fingers or a speculum. A PROM also means you'll probably have to be on bed rest until normal labor occurs.

These are not happy situations, so whatever can be done to alleviate either of them may be quite useful. Some new research has provided hope that PROM can be prevented.

A new study shows that vitamin C can protect against rupture of the amniotic membranes prematurely and help keep your baby safe.

One hundred twenty-six women in their 20th week of pregnancy were invited to participate; 120 accepted. All the women were randomly assigned to receive either 100 mg of vitamin C or a placebo (pill with no active ingredients). The researchers, the women, and the health care staff were not informed who received the vitamin C; this is called a double-blind study.

Every week the researchers measured the level of vitamin C in the blood plasma and white blood cells. Each woman was evaluated to make sure she didn't have a cervical or vaginal infection. The researchers also recorded the incidence of premature rupture of the membranes.

The average plasma vitamin C concentrations decreased significantly throughout the pregnancy in both groups. The probability this result could happen by chance was very low and equaled .001. No significant differences between groups appeared until weeks 20 and 36. At that point, the average white blood cell concentration of vitamin C decreased in the placebo group and increased in the group taking vitamin C. The incidence of PROM was 14 per 57 pregnancies (24.5%) in the placebo group and 4 per 52 pregnancies (7.69%) in the group taking vitamin C. This means the group that didn't take vitamin C had 3 times more prematurely ruptured membranes than the group who took the supplement.

The researchers concluded that taking 100 mg vitamin C after 20 wk of pregnancy effectively lessens the incidence of premature rupture of the membranes..

Casanueva E, Ripoll C, Tolentino M, Morales RM, Pfeffer F, Vilchis P, Vadillo-Ortega F. Vitamin C supplementation to prevent premature rupture of the chorioamniotic membranes: a randomized trial. Am J Clin Nutr. 2005 Apr;81(4):859-63.

This article is for information purposes only. For treatment, consult your health care practitioner.