Post-meal blood sugar control in women using birth-control pills or a hormonal IUD

Exploring the Effect of Hormonal Contraceptives on Postprandial Glucose Handling in Young Healthy Females

Observational McMaster University · NCT07169591

We will test whether blood sugar control after a standard glucose drink differs in healthy women aged 18-45 who are naturally cycling, taking specific combined birth-control pills, or using a levonorgestrel IUD.

Quick facts

Study typeObservational
Enrollment54 (estimated)
Ages18 Years to 45 Years
SexFemale
SponsorMcMaster University Academic / other
Locations1 site (Hamilton, Ontario)
Trial IDNCT07169591 on ClinicalTrials.gov

What this trial studies

This observational study compares postprandial glucose and insulin responses in three groups of young, healthy females: naturally cycling (NAT), users of specified combined oral contraceptives (OCP), and users of levonorgestrel-releasing IUDs (IUD). Participants complete a 75 g oral glucose tolerance test with blood samples taken every 15–30 minutes over two hours to measure glucose, insulin, and related metabolic markers. The study also measures circulating estrogen and progesterone (and synthetic analogs) to explore links between sex-hormone levels and glucose handling. Enrollment is restricted to females 18–45 with BMI 18.5–30 and excludes people with diabetes, PCOS, smoking, pregnancy, or other major medical conditions.

Who should consider this trial

Good fit: Ideal participants are otherwise healthy females aged 18–45 with BMI 18.5–30 who are either regularly cycling, have used specified monophasic levonorgestrel combined OCPs for >3 months, or have had a levonorgestrel IUD in place for ≥3 months.

Not a fit: Patients with diabetes, polycystic ovary syndrome, active smoking, pregnancy or breastfeeding, BMI outside 18.5–30, or using contraceptives other than the specified formulations are unlikely to benefit or be eligible.

Why it matters

Potential benefit: If successful, the results could help women and clinicians choose contraceptive methods with lower long-term risks to blood-sugar regulation and future metabolic disease.

How similar studies have performed: Prior research provides mixed evidence that hormonal contraception can alter glucose tolerance, and direct comparisons using these specific monophasic levonorgestrel pills and levonorgestrel IUDs are limited.

Eligibility criteria

Show full inclusion / exclusion criteria
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.

Where this trial is running

Hamilton, Ontario

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Glucose HomeostasisGlucoseInsulinFemale HealthHormonal ContraceptiveIntrauterine DeviceOral Contraceptive Pill
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.