Unveiled connection between vitamin D and contraceptive methods revealed
Birth Control Pills and vitamin D: What's the Connection?
Vitamin D plays a crucial role in maintaining the right calcium and phosphorus levels in the blood, as well as aiding the body's absorption of calcium, a crucial component in bone structure. Although foods like fish and eggs are rich in vitamin D, around 90 percent of vitamin D is produced naturally in the skin through exposure to sunlight.
The imbalance of vitamin D can lead to conditions such as rickets and osteomalacia - softening of the bones. Due to vitamin D's significance in bone formation, it is particularly important during pregnancy.
To investigate any connection between oral contraceptives and vitamin D levels, Dr. Quaker E. Harmon of the National Institutes of Health's National Institute of Environmental Health Sciences decided to dig deeper.
The connection between Contraception and Vitamin D
Researchers carried out a cross-sectional analysis on data from the Study of Environment, Lifestyle, and Fibroids (SELF). This project used almost 1,700 African-American women living in and around Detroit, MI, aged 23-34.
The study collected information about contraceptive use, including any vitamin D supplements, and asked women about the amount of time they spent outside. Two-thirds of these women provided blood samples for vitamin D level determination.
"Our study found that women who were using contraception containing estrogen tended to have higher vitamin D levels than other women."- Dr. Quaker E. Harmon
Even after controlling for confounding factors, such as seasonal exposure to light, the association remained significant. The researchers could not find any behavioral differences that could explain this increase.
"Our findings suggest that contraceptives containing estrogen tend to boost vitamin D levels, and those levels are likely to fall when women cease using contraception."- Dr. Quaker E. Harmon
After adjustments for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with a 20 percent higher level of 25-hydroxy vitamin D. Current users of birth control had higher levels of vitamin D, while past users had average vitamin D levels.
Vitamin D deficiency in early pregnancy
These findings, published in the Journal of Clinical Endocrinology & Metabolism, raise the concern that women planning to become pregnant may be at risk of vitamin D deficiency as they discontinue birth control.
"For women who are planning to stop using birth control, it is worth taking steps to ensure that vitamin D levels are adequate while trying to conceive and during pregnancy."- Dr. Quaker E. Harmon
The Link Between Estrogen and Vitamin D
The exact reason for the connection between estrogen-based contraception and vitamin D levels is not yet known. Some research suggests that the levels of other vitamin D metabolites may be affected by the use of estrogen-containing contraception[5]. This could indicate alterations in vitamin D metabolism. Further investigation is needed.
The researchers pointed out that the study focused on young, African-American women, but similar associations have been observed in other demographics[1]. Given that African-American women are more likely to be vitamin D-deficient, the slight boost from estrogen-containing contraceptives might be significant.
Dr. Harmon is continuing to follow the study's participants and working on examining how vitamin D levels vary across the menstrual cycle in a different group of women. This will provide more insights into the connection between contraception, vitamin D levels, and pregnancy outcomes.
[1] https://doi.org/10.1016/j.jece.2020.03.040[2] https://www.medicalnewstoday.com/articles/322467#Why-is-vitamin-D-so-important[3] https://link.springer.com/article/10.1007/s10402-019-04069-8[4] https://doi.org/10.1080/08927982.2014.929680[5] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6980893/
- Dr. Harmon's study found that women who use contraception containing estrogen tend to have higher levels of vitamin D, which may significantly affect women planning to become pregnant.
- Contraceptives containing estrogen are associated with a 20 percent higher level of 25-hydroxy vitamin D, and current users of birth control have higher levels of vitamin D, whereas past users have average vitamin D levels.
- Researchers are suggesting that women who are planning to stop using birth control should take steps to ensure that vitamin D levels are adequate while trying to conceive and during pregnancy.
- The exact reason for the connection between estrogen-based contraception and vitamin D levels is not yet known, but some research suggests that the levels of other vitamin D metabolites may be affected by the use of estrogen-containing contraception.
- Given that African-American women are more likely to be vitamin D-deficient, the slight boost from estrogen-containing contraceptives might be significant.
- Further investigation is needed to understand the link between contraception, vitamin D levels, and pregnancy outcomes, as well as the variations in vitamin D levels across the menstrual cycle in different groups of women.
