Influence of Strict Lockdown on Vitamin D Deficiency in Pregnant Women: A Word of Caution 

Pregnant women had an increased prevalence of vitamin D deficiency during a strict COVID-19 lockdown period. 

• Participants in the SL group had lower mean serum 25(OH)D levels (14.2 ng/mL vs. 20.5 ng/mL, p < 0.01) and a higher prevalence of vitamin D deficiency (77.8% vs. 50.1%, p < 0.01) compared to the non-lockdown group.  
• No other variables were significantly different in relation to strict lockdown, including prevalence of gestational diabetes or BMI. Only triglycerides were significantly higher in the SL group, and nutritional and lifestyle items scored lower in the study questionnaire. 

866 women in Spain who were pregnant during a strict COVID-19 lockdown period from March 15, 2020 to May 15, 2020.

• The study results are based only on a single 25(OD)D measurement and did not consider changes that may have occurred over time.  
• The authors note that the study did not take into account the amount or duration of sunlight exposure for each individual participant. The variations in sunlight exposure between the participants may have biased the results.  

Our results revealed that VDD prevalence in pregnant women was influenced by [strict lockdown]. This valuable information could guide us in the future to take action, such as with vitamin D supplementation, in the case that public officials order the population to stay indoors for any given reason.

• This single-center, population-based, observational study was carried out from September 2019 to August 2020 in Elda, Spain, and was initially designed to investigate the relationship between vitamin D deficiency and gestational diabetes mellitus in relation to body mass index (BMI). 
• Due to the emergence of COVID-19, a significant cohort experienced a strict lockdown in their geographical area from March 15, 2020, to May 15, 2020. An additional retrospective analysis was performed to evaluate the impact of quarantine on vitamin D deficiency in pregnant women.  
• During a second trimester visit, serum 25(OH)D was measured, and patients were screened for gestational diabetes. To determine if the prevalence of vitamin D deficiency (VDD) in the local population of pregnant women was influenced by strict lockdown (SL), a retrospective cross-sectional study was conducted to estimate the prevalence odds ratio (POR) for the association of VDD and SL. A logistic regression model was used and adjusted by the biweekly measured vitamin D-specific UVB dose in the geographical area to control seasonal variations in sunlight irradiation.  

Agüero-Domenech N, Bernabeu E, García-Valentín A, Sarrión A, Jover S, Baranda J, Cortés-Castell E, Gil-Guillén V, García-Teruel MJ. Influence of Strict Lockdown on Vitamin D Deficiency in Pregnant Women: A Word of Caution. Nutrients. 2023; 15(8):1972. https://doi.org/10.3390/nu15081972.