Reena was diagnosed with gestational diabetes 22 weeks into her pregnancy and initially managed the condition through dietary changes. Despite being vigilant about her food choices, her blood sugar levels became increasingly challenging to control as her pregnancy advanced, presenting physical and emotional challenges that affected her mood and overall well-being. The prospect of needing additional medications or insulin during pregnancy was a concern for Reena because it could lead to a more medicalized childbirth experience, which she wanted to avoid.
To alleviate her struggles with gestational diabetes, Reena’s healthcare team prescribed Metformin, a medication known for its effectiveness in managing blood sugar levels. Metformin provided more flexibility in her dietary choices, allowing her to enjoy a broader range of foods while maintaining stable blood sugar levels. This medication also improved her mood and energy levels, making her pregnancy experience more manageable.
Reena’s story highlights the efficiency of Metformin in pregnancy. In recent years, this medicine has gained attention as a potential treatment option for pregnant individuals with gestational diabetes and other metabolic conditions. This article explores the critical details of Metformin use during pregnancy, shedding light on its potential impact on maternal and fetal health.
What is Metformin?
Metformin is a prescription medicine that treats type 2 diabetes mellitus. It belongs to a class of drugs known as biguanides and lowers blood sugar levels in type 2 diabetes patients. Metformin is typically taken orally as tablets or liquid and is often the first-line treatment for type 2 diabetes, particularly for overweight or obese individuals. It can be used alone or with other diabetes medications, including insulin. Its primary and most well-established use is for diabetes management, but some healthcare providers may prescribe Metformin for other conditions, including polycystic ovary syndrome (PCOS) and, in some cases, for weight management.
How does Metformin work during pregnancy?
Metformin may help manage blood sugar levels in pregnant women with gestational diabetes. Doctors sometimes prescribe it during pregnancy, and its mechanism of action is similar to its action in non-pregnant individuals, but a healthcare provider should carefully monitor its use and effects. Here is an overview of how Metformin works during pregnancy:
- Gestational Diabetes Management: Gestational diabetes develops during pregnancy due to elevated blood sugar levels, and Metformin may help manage these levels in pregnant women with gestational diabetes.
- Insulin Sensitivity Improvement: Metformin improves insulin sensitivity in the body’s cells, making them respond more effectively to insulin. The body’s insulin resistance naturally increases during pregnancy due to hormonal changes, and Metformin can help counteract this resistance, allowing insulin to work more efficiently in lowering blood sugar levels.
- Reduction of Excessive Glucose Production: Metformin can reduce the excessive glucose production by the liver, a common issue in individuals with gestational diabetes. By limiting the liver’s glucose output, Metformin helps prevent spikes in blood sugar levels, particularly after meals.
- Weight Management: Metformin may also help with weight management during pregnancy, essential for maternal and fetal health. Some women with PCOS, often treated with Metformin, may be more susceptible to gestational diabetes during pregnancy, and managing weight can be one way to mitigate this risk.
Safety and Efficiency of Metformin in Pregnancy
A study in 2018 explored the use of Metformin in the context of gestational diabetes (GDM) and its impact on pregnancy outcomes. Here are the key findings:
- Gestational Diabetes Classification: Medical professionals have tried distinguishing between women who develop overt diabetes, pre-existing diabetes first recognized during pregnancy, and gestational diabetes linked to pregnancy-induced insulin resistance. They classify diabetes during pregnancy as either pre-gestational (existing diabetes before pregnancy) or gestational (developing during pregnancy).
- Prevalence of Gestational Diabetes: The prevalence of gestational diabetes (GDM) is increasing worldwide because of maternal age and rising obesity rates. The variation in diagnostic criteria between countries makes it challenging to compare prevalence rates.
- Evidence from Metformin Trials: The study draws evidence from randomized controlled trials and case-control observational studies, focusing on the Metformin in Gestational Diabetes (MiG) trial.
- MiG Trial: Researchers randomized pregnant women with GDM to receive either Metformin or insulin. While a significant proportion of women in the Metformin group required supplementary insulin, the primary outcome – a composite of neonatal complications – showed no significant difference between the two treatment groups.
- Maternal Weight Gain: Women on Metformin gained less weight during pregnancy than women on insulin. Other secondary outcomes, such as birthweight and neonatal measures, were similar between the Metformin and insulin groups.
- Patient Acceptability: Metformin had higher patient acceptability, with many women expressing a preference for it in subsequent pregnancies.
- Case-Control Studies: Additional case-control observational studies supported the benefits of Metformin, including lower maternal weight gain, reduced neonatal morbidity, and no significant difference in the incidence of large babies.
- Comparisons with Other Treatments: Metformin showed advantages in terms of post-prandial (post-meal) glucose levels in some studies. It did not increase the risk of preterm delivery or Caesarean section but was associated with lower risks of large babies, neonatal hypoglycemia, admission to neonatal intensive care units, and reduced rates of pregnancy-induced hypertension.
- NICE Instruction: The National Institute for Health and Care Excellence (NICE) recommends offering Metformin to women with gestational diabetes if they do not achieve blood glucose targets through dietary and exercise modifications within one to two weeks. Insulin is an alternative if Metformin is contraindicated or unacceptable to the woman.
When used under the guidance of a healthcare provider, Metformin can safely and effectively manage gestational diabetes and specific metabolic conditions during pregnancy. It is essential to base the decision to use Metformin on a thorough evaluation of the individual’s medical situation and monitor its use throughout pregnancy to ensure the best possible outcome for both the mother and the baby.
Doctor’s Recommendation
In the past, insulin was the only acceptable way to treat diabetes during pregnancy. However, many clinicians have since suspected that metformin is also safe and effective. Running clinical trials on pregnant women is extremely difficult, but if the patient’s healthcare institution is open to using metformin instead of insulin, it would be preferable, especially for patients with pre-existing obesity. Administering insulin often leads to significant weight gain.
It is also important to note that slightly higher blood glucose levels may be acceptable during pregnancy because human placental lactogen causes some degree of insulin resistance, allowing the baby to obtain glucose before the mother. Thus, stringent glucose control may not be necessary. Some organizations, such as NICE and SMFM, actually consider metformin as a first-line treatment.
Therefore, if a pregnant patient with a BMI over 30 is denied metformin therapy, they should consider seeking a second opinion from other healthcare professionals.
