The NIH funded a large study to look at an epidemiological link between Vit D and Pre eclampsia. The conclusion, after adjusting for covariates, was that Vitamin D sufficiency was associated with a reduction in severe pre eclampsia but had not impact upon mild pre eclampsia, suggesting a different clinicopathological role in the two conditions. However, the link remains an association. The next step would be intervention trials to test the hypothesis that supplementation to create sufficiency in a deficient state reduced pre eclampsia, but it may be hard to randomise women with deficiency to placebo.
Yes, there is a significant relationship between vitamin D deficiency and preeclampsia. When vitamin D is unsufficient, the risk of preeclampsia will increase.
Please take a look at the research: The role of vitamin D in pre-eclampsia: a systematic review. By Juhi M. Purswan, et al. BMC Pregnancy Childbirth. 2017; 17: 231.
Article The role of vitamin D in pre-eclampsia: A systematic review