Effect of the intra-uterine system, Mirena, on bone density

To compare the bone mineral density (BMD) of women who have used the levonorgestrel-releasing intra-uterine system Mirena for 4 to 6 years with women who have not been exposed to exogenous hormones or pregnancy for the previous 5 years.

Status

Completed

Phases

Unknown

Study type

Observational

Source

ANZCTR

Registry ID

ACTRN12608000122358

Enrollment

Registered

2008-03-06

Start date

2008-03-04

Completion date

2009-09-30

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Objective: To determine if the levonorgestrel-releasing intrauterine system Mirena® affects bone mineral density (BMD). Design: Cross-sectional study Setting: Dunedin School of Medicine, University of Otago Patients: BMD was compared between women aged 30 to 47 who had a current Mirena® inserted for 4 to 6 years and matched (age, BMI, smoking, and ethnicity) controls who had not been exposed to exogenous hormones or pregnancy for the previous 5 years. Interventions: BMD was measured by double xray absorptiometry (DEXA) of the lumbar spine and proximal femur. Main outcome measures: BMD of the lumbar spine and proximal femur. BMD z-scores were also recorded. Mixed models were used to estimate effects of Mirena® use with a random pair effect to accommodate the clustered design. Potential confounders were parity, gravidity, physical activity as well as matching variables that altered the effect by 15% or more.

Interventions

Mirena use for 4 to 6 years. The Mirena intrauterine device (IUD) is a long acting contraceptive, an effective treatment for heavy menstrual bleeding and is approved for use with hormone replacement therapy (HRT) to provide endometrial protection. This T-shaped plastic device is placed within the uterus and releases the progestagen levonorgestrel into the uterine cavity with some absorption of levonorgestrel into the systemic circulation. Each device is registered for use as a contraceptive for

Eligibility

Sex/Gender

All

Age

30 Years to 47 Years

Healthy volunteers

Yes

Inclusion criteria

Women 30 to 47 years old who have used a Mirena for 4 to 6 years (exposed group) and women who have not been exposed to exogenous hormones or pregnancy for the previous 5 years (control group).

Exclusion criteria

History of chronic illness, metabolic bone disease. Taking medications known to affect bone or mineral metabolism, or any other hormonal medication taken in the previous 5 years. Pregnancy in the previous 5 years.

Outcome results