Postprandial Glucose Handing in Contraceptive and IUD Users

Insulin resistance is a common metabolic condition, and is considered a primary risk factor for the development of type 2 diabetes (T2D). As the prevalence of T2D continues to rise, particularly among premenopausal females (18-45 years), it is imperative to conduct additional research in this area. Fluctuations in primary sex hormones in females have been shown to modulate risk for developing impaired glucose tolerance, however, research in this area as well as work investigating synthetic versions of these hormones for OCP and IUD users remains unclear. It is crucial to investigate how hormonal contraceptives can alter glucose tolerance in young, otherwise healthy females, and what downstream effects contraceptives could have later in life.

Inclusion criteria

• Within 18-45 years
• BMI between 18.5 and 30.0 kg/m2
• Weight stable for the past 6 months (± 2kg)
• VO2peak values within a below average to above average rangea
• Fasting blood glucose <6.0 mMb
• Resting blood pressure <140/90 mmHg

NAT females:

• Regular menstrual cycle for > 6 months (defined as a cycle length of 21-35 days)

OCP users:

• Use of combined OCPs as prescribed for > 3 months
• Second generation levonorgestrel drugs only
• Monophasic formulations only (Alesse, Alysena, Audrina, Aviane, Min-Ovral, Ovima, or Portia)

IUD users:

• Insertion of IUD no fewer than 3 months prior to beginning of study
• Hormonal, levonorgestrel-releasing IUD (Kyleena or Mirena)

Exclusion criteria

• Smoking
• Diabetes, cancer, or other metabolic disorders
• Cardiac or gastrointestinal problems
• Infectious disease
• Barium swallow or nuclear medicine scan in the previous 3 weeks
• Pregnant or breastfeeding
• Diagnosis of polycystic ovary syndrome
• Endometriosis
• Use of emergency contraception (e.g., Plan B) within the previous 3 months

NAT females:

• Use of any type of hormonal contraceptive in the previous 3 months

OCP users:

• Not using OCP as prescribed (e.g. missing doses or taking drug inconsistently)
• Use of OCP for longer than 3 years.

IUD users:

• Insertion of Kyleena IUD longer than 2 years.
• Insertion of Mirena IUD longer than 4 years.