Connection between vitamin D levels and birth control methods under investigation
Women using estrogen-based contraceptives have higher levels of vitamin D in their circulation, a new study shows. Similarly, a significant drop in vitamin D levels follows when these contraceptives are discontinued.
Vitamin D plays a primary role in maintaining healthy levels of calcium and phosphorus in the blood. It also aids in absorbing calcium, an essential component of bones. Food sources rich in vitamin D include fish and eggs, while the body produces about 90% of the vitamin through a chemical reaction after sun exposure.
Deficiency in vitamin D can lead to rickets and osteomalacia, which causes bones to soften. As vitamin D is vital for bone formation, it is particularly important during pregnancy.
The National Institutes of Health's National Institute of Environmental Health Sciences in Research Triangle Park, North Carolina, investigated the association between vitamin D levels and oral contraceptives. Researchers carried out a cross-sectional analysis of data from the Study of Environment, Lifestyle, and Fibroids, an investigation of reproductive health. They analyzed 1,662 African-American women aged 23-34 living near Detroit, Michigan.
The study asked women about contraceptive use, outdoor time, and any vitamin D supplements they took. Blood samples were collected to measure the most common form of circulating vitamin D, known as 25-hydroxy vitamin D.
The study found that women using contraceptives containing estrogen had higher vitamin D levels compared to other women. After controlling for confounding factors, such as seasonal exposure to light, the effect remained significant. The researchers could not find any behavioral differences, like increased time spent outdoors, to explain the increase in vitamin D levels.
The use of contraceptive pills, patches, or rings containing estrogen was associated with 20% higher levels of 25-hydroxy vitamin D, the study shows. Current users of birth control had higher vitamin D levels, while past users had average vitamin D levels.
The findings, published in the Journal of Clinical Endocrinology & Metabolism, suggest that discontinuing estrogen-based contraceptives could potentially increase the risk of vitamin D deficiency, especially among women planning pregnancy.
Researchers are unsure why estrogen-based contraception might affect vitamin D levels. They believe there may be alterations in the metabolism of vitamin D, but further work is needed to confirm this. The study looks solely at African-American women, but the same association has been observed in women of other races.
Women planning to stop using birth control are advised to ensure adequate vitamin D levels while trying to conceive and during pregnancy. Low vitamin D during pregnancy can increase the risk of complications, such as preeclampsia, gestational diabetes, preterm birth, and impaired fetal skeletal development.
Supplementation may be necessary after discontinuing estrogen-based contraceptives, but always under the guidance of a healthcare professional.
- Women using contraceptives containing estrogen have higher levels of vitamin D in their circulation, as indicated by the new study.
- The National Institutes of Health's study on oral contraceptives and vitamin D levels found a significant association between estrogen-based contraceptives and higher vitamin D levels.
- After controlling for confounding factors, African-American women using contraceptives containing estrogen had about 20% higher levels of 25-hydroxy vitamin D compared to other women.
- Deficiencies in vitamin D during pregnancy can lead to complications such as preeclampsia, gestational diabetes, preterm birth, and impaired fetal skeletal development.
- While further research is needed to understand why estrogen-based contraception affects vitamin D levels, women planning to stop using birth control are advised to ensure adequate vitamin D levels while trying to conceive and during pregnancy.
- Supplementation may be necessary after discontinuing estrogen-based contraceptives, but always seek the guidance of a healthcare professional for proper nutrition and women's health recommendations.
