EXECUTIVE SUMMARY

Strokes and heart attacks are rare for women with diabetes who use hormonal contraception, with intrauterine devices and implants serving as the safest options, according to a just-published analysis.

  • Highly effective, intrauterine and subdermal contraceptives are excellent options for women with diabetes who hope to avoid the teratogenic effects of hyperglycemia by carefully planning their pregnancies, the study’s authors noted.
  • For women 18-79 years of age, age-adjusted incidence of diagnosed diabetes has increased since the 1980s; in 1980, the age-adjusted incidence rate was 3.5, while in 2014, it was 6.5.

Strokes and heart attacks are rare for women suffering from diabetes who use hormonal contraception, with intrauterine devices (IUDs) and implants the safest options, according to a just-published analysis.1

This finding is important news for family planning providers and their patients. According to the CDC, 29.1 million people, or 9.3% of the U.S. population, suffer from diabetes. Of this number, 21 million are diagnosed, and 8.1 million are undiagnosed.2 The incidence of diabetes among women of reproductive age (18-44 years) increased from 2.2 to 3.8 per 1,000 women between 1997 and 2013.3 The prevalence of diabetes varies in different racial and ethnic groups, with American Indians and Alaskan Natives exhibiting the highest prevalence — more than twice that of non-Hispanic whites.2

The study, one of the first to evaluate hormonal contraception and health outcomes in women presenting with a chronic condition, should encourage providers to include implants and IUDs in birth control discussions with diabetic patients.

“Clinicians need to get beyond the idea that birth control just means ‘the Pill,’” says Eleanor Bimla Schwarz, MD, MS, professor of internal medicine at UC Davis Health System and senior author of the study. “There are options that are safe and effective for all women, including those with diabetes.”

Review the Research

To conduct the study, researchers used 2002-2011 data from the Clinformatics Data Mart, a national health claims database that includes 15 million commercially insured people. The scientists identified women in the United States, ages 14-44 years, with an ICD-9-CM code for diabetes and a prescription for a diabetic medication or device. They examined contraceptive claims and compared time to thromboembolism (venous thrombosis, stroke, or myocardial infarction) among women with diabetes dispensed hormonal contraception, using a modification of Cox regression to control for age, smoking, obesity, hypertension, hyperlipidemia, diabetic complications, and history of cancer. The analysis excluded data for three months after women gave birth.1

The analysis identified 146,080 women with diabetes who experienced 3,012 thromboembolic events. Only 28% of reproductive-age women with diabetes submitted any claims for hormonal contraception, with the majority receiving estrogen-containing oral contraceptives. Further investigation indicated incidents of thromboembolism were highest among women who used the contraceptive patch (16 per 1,000 woman-years) and lowest among women who used IUDs (six per 1,000 woman-years) and subdermal implants (zero per 163 woman-years). Compared with use of intrauterine contraception, progestin-only injectable contraception was associated with increased risk of thromboembolism (12.5 per 1,000 woman-years; adjusted hazard ratio, 4.69; 95% confidence interval [CI], 2.51-8.77).1

“The absolute risk of thromboembolism among women with type 1 or 2 diabetes using hormonal contraception is low,” researchers concluded. “Highly effective, intrauterine and subdermal contraceptives are excellent options for women with diabetes who hope to avoid the teratogenic effects of hyperglycemia by carefully planning their pregnancies.”

The findings of this paper suggest that for women presenting with diabetes, implant and IUD contraception represent the safest birth control choices, while combination methods, as well as the contraceptive injection, represent choices associated with greater risk, notes Andrew Kaunitz, MD, University of Florida Research Foundation professor and associate chairman of the department of obstetrics and gynecology at the University of Florida College of Medicine-Jacksonville.

“Given how prevalent diabetes has become among our reproductive-age patients, the findings of this study are important,” Kaunitz says.

What are Women with Diabetes Using?

Outcomes from this study indicate that the vast majority of women with diabetes (72%) did not receive prescription contraception of any kind, even though pregnancy planning is critical for this population. This finding is “alarming,” since women suffering from diabetes become pregnant as often as other women, notes Sarah O’Brien, MD, lead author of the article and associate professor at The Ohio State University.

“Pregnancy timing is critical for women with diabetes,” O’Brien said in a release accompanying the study. “It’s best to carefully plan pregnancies and ensure that the diabetes is under good control, because high sugars can cause an increased chance of birth defects.”

Women are at high risk for diabetes if they are overweight (body mass index of 25 kg/m2 or greater) and exhibit one or more of the following additional risk factors:

  • low physical activity (less than 150 minutes of moderate-intensity activity, such as walking, per week);
  • family history of type 2 diabetes;
  • high-risk race/ethnicity (African American, American Indian or Alaska Native, Asian American, Hispanic or Latino, Native Hawaiian or Pacific Islander);
  • have birthed a baby weighing nine pounds or more, or were diagnosed with gestational diabetes;
  • high blood pressure (140/90 mmHg or higher);
  • high cholesterol (240 mg/dL or higher); or
  • history of polycystic ovarian syndrome.4

Stress Importance of Planning

Women with diabetes who are planning for pregnancy should know that high blood sugar and teratogenic medications increase the risk of congenital anomalies. By planning their pregnancies, patients can achieve tight control, stop taking teratogens, stabilize comorbidities, and begin folate supplementation prior to conception. Multidisciplinary support will be needed to achieve tight control, with a goal of A1c levels of 7% prior to pregnancy, and 6% during pregnancy, if this can be achieved without hypoglycemia. Women with diabetes also are encouraged to take at least 600 mcg of folic acid per day. A baseline ophthalmology exam should be performed during the first trimester, with monitoring every trimester as indicated by degree of retinopathy.5 (Editor’s Note: For more information, please see the webinar, “Managing Diabetes: Increasing Provider Understanding of Reproductive Health Implications” [http://bit.ly/1Ylz0K1], and click on the individual presentations.)

For women who are not planning pregnancy, check the U.S. Medical Eligibility Criteria for Contraceptive Use (US MEC) for guidance.6 Women with diabetes are eligible candidates for a contraceptive that contains estrogen; use of combination pills, the contraceptive patch, and the vaginal ring for women with a history of gestational diabetes are classified as Category 1 (no restrictions for use), while use in women with type 1 or type 2 diabetes with no evidence of vascular disease falls in Category 2, meaning the chosen method generally can be used, with follow-up as needed. For women with diabetes and complications (nephropathy, retinopathy, neuropathy, or other vascular disease) or diabetes of more than 20 years’ duration, use of estrogen-containing methods falls in Category 3 (usually not recommended; clinical judgment and continuing access to clinical services are required for use) or Category 4 (should not be used), depending on the severity of the condition.6

REFERENCES

  1. O’Brien SH, Koch T, Vesely SK, Schwarz EB. Hormonal contraception and risk of thromboembolism in women with diabetes. Diabetes Care 2017;40:233-238.
  2. Centers for Disease Control and Prevention. 2014 National Diabetes Statistics Report. Available at: http://1.usa.gov/1Dtcela. Accessed Jan. 20, 2017.
  3. Yehuda I. Implementation of preconception care for women with diabetes. Diabetes Spectr 2016;29:105-114.
  4. Centers for Disease Control and Prevention. Women at High Risk of Diabetes. Fact sheet. Available at: http://1.usa.gov/24JYz7s. Accessed Jan. 20, 2017.
  5. Gawron L. Managing Diabetes: Increasing Provider Understanding of Reproductive Health Implications. Available at: http://bit.ly/2k9BlY6.
  6. Centers for Disease Control and Prevention. U.S. medical eligibility criteria for contraceptive use, 2010. MMWR 2010;59(RR04):1-86.