While in labor, preterm birth delayed 6 days by Vitamin D (single dose of 50,000 IU) - RCT
Investigating the Effect of a Single Dose of Vitamin D in Mothers With Labor Symptoms on the Delay of Preterm Birth, A Double-Blind Clinical Trial Study
Topics in Clinical Nutrition 40(4):p 276-283, October/December 2025. | DOI: 10.1097/TIN.0000000000000389 PDF behind paywall
Zakerihamidi, Maryam PhD; Saghafi, Nafiseh MD; Maamouri, Gholamali MD; Ataee Nakhaei, Mohammad Hosein MD; Darabi, Azadeh MD; Rasti, Morteza MD; Boskabadi, Hassan MD - Iran
This study investigated the effect of maternal vitamin D intake on delayed delivery time. A randomized, controlled trial was conducted on 175 mothers with preterm labor (intervention group: 89, control group: 86). A dose of 50 000 IU of vitamin D was provided to the intervention group. Neonatal, maternal, and laboratory data were collected.
Mothers supplemented with vitamin D gave birth 7.38 ± 7.17 days,
while mothers in the control group gave birth 1.09 ± 3.13 days
after the onset of birth symptoms (lightening, bloody show, rupture of membranes, nesting, effacement, and dilation).
Administering 50 000 IU of vitamin D in pregnant women with premature delivery symptoms was associated with delayed delivery time.
Comments by VitaminDWiki founder
I had not seen a hint that vitamin D would help so late in the pregnancy
Probably used injection in this study (several of the authors had used injection in their previous studies)
- Even better than Injection - fast-acting nanoemulsion vitamin D
Vitamin D before, during, and after pregnancy would be better in scores of ways
50,000 IU weekly or bi-weekly - best started 2 months before conception and continued at least thru breastfeeding
The father should also take the same dosing for 2 months before conception
Reminds me of some other emergency uses of Vitamin D
Take loading dose at the first sign of a possible viral infection. Example: COVID
Take vitamin D before surgery
I inhale Vitamin D about 5 minutes before intense exercise sessions since 2015
Related in VitaminDWiki
Preterm birth and low Vitamin D - many studies
- Preterm birth 7 times more likely if low vitamin D 1 month before – May 2023
Hospital costs for an extreme preemie adds 58,000 dollars to the cost of full term birth – Dec 2022
Preterm birth rate increased in US but decreased in Finland (high Vitamin D) - Jan 2024