Estrogen-Based Birth Control and Vitamin D Levels
Uncovered link unearths potential link between vitamin D and contraceptives in pregnancy
Researchers have discovered that women using estrogen-containing contraceptives have higher circulating levels of vitamin D, whereas those who discontinue these drugs experience a significant drop in vitamin D levels.
Vitamin D plays a pivotal role in maintaining the correct balance of calcium and phosphorus in the blood, as well as aiding in the body's absorption of calcium, an essential component of bones. Vitamin D can be found in various foods, such as fish and eggs, and around 90% of the vitamin is produced in the skin via a chemical reaction triggered by sunlight exposure.
Deficiency in vitamin D can lead to skeletal disorders like rickets and osteomalacia, characterized by softened bones. Given vitamin D's importance in the formation of bones, it is particularly significant during pregnancy.
Dr. Quaker E. Harmon, of the National Institutes of Health's National Institute of Environmental Health Sciences, investigated any alterations in vitamin D levels linked to taking oral contraceptives. The research team conducted a cross-sectional analysis of data from the Study of Environment, Lifestyle, and Fibroids (SELF), a project focusing on reproductive health. The study consisted of almost 1,700 African-American women, aged 23-34, living in and around Detroit, MI.
The study asked women about their contraceptive usage, spending habits outside, and any vitamin D supplements taken. Blood samples were collected from 1,662 women to determine levels of the most common circulating form of vitamin D, called 25-hydroxy vitamin D.
The study findings showed that women using contraception containing estrogen had higher vitamin D levels compared to others. Even after controlling for confounding factors, such as seasonal exposure to light, the effect remained significant.
"Our study found that women who were using contraception containing estrogen tended to have higher vitamin D levels than other women," said Dr. Harmon. After adjustments for confounding variables, the use of contraceptive pills, patches, or rings containing estrogen was associated with 20 percent higher levels of 25-hydroxy vitamin D.
The researchers noted that current users of birth control had higher levels of vitamin D, and past users had average vitamin D levels. As women start trying to conceive and ensure adequate vitamin D levels during pregnancy, they may run the risk of becoming deficient in vitamin D while transitioning off birth control.
The current study focused solely on African-American women. However, the same association has been observed in women not of African-American descent; thus, race might not play a significant role in this effect. Nonetheless, African-American women are more likely to be vitamin D-deficient, which could make small changes or decreases in their vitamin D concentrations more critical.
Dr. Harmon is continuing to follow this group of women to further investigate the relationship between contraception and vitamin D levels and is also working on another group of participants to explore how vitamin D varies across the menstrual cycle.
In conclusion, the study highlights an association between estrogen-based contraception and vitamin D levels. Further research is necessary to understand the mechanisms behind this effect and its potential racial differences. Women planning to discontinue birth control may wish to pay extra attention to their vitamin D levels to prevent deficiencies during pregnancy.
[References omitted for brevity]
- The role of vitamin D in maintaining proper calcium and phosphorus balance in the blood, and its aid in absorbing calcium, the essential component of bones, is well-known in the field of health-and-wellness and nutrition.
- Deficiencies in vitamin D can result in skeletal disorders like rickets and osteomalacia, characterized by softened bones, making its importance especially significant during pregnancy.
- In a study focusing on reproductive health, Dr. Quaker E. Harmon from the National Institutes of Health discovered that women using contraception containing estrogen had higher vitamin D levels compared to others.
- The study showed that after controlling for confounding factors such as seasonal exposure to light, the use of contraceptive pills, patches, or rings containing estrogen was associated with 20 percent higher levels of 25-hydroxy vitamin D.
- A potential concern for women transitioning offbirth control and attempting to conceive is the possibility of becoming deficient in vitamin D, due to the higher levels of the vitamin while using hormonal contraceptives.
- Multi-nutrient women's vitamins containing vitamin D may be beneficial for women planning to discontinue birth control, to help ensure adequate vitamin D levels during the transition and pregnancy, addressing potential deficiencies in this critical nutrient.
