Wegovy and the STEP UP Trial Results: What You Need to Know

Have you been searching for an effective solution to manage blood sugar levels or support weight loss? For many, managing diabetes or losing weight can feel like a constant struggle, with diets and treatments often failing to deliver lasting results. But what if there was a medication that could effectively help manage both blood glucose levels and weight? Enter semaglutide, a peptide classified as a GLP-1 (glucagon-like peptide-1) receptor agonist that has rapidly gained recognition for its potential to address both of these challenges.

Semaglutide works by mimicking the actions of GLP-1, a hormone that plays a critical role in regulating appetite and blood sugar. With its unique dual benefit, semaglutide has shown the potential to help individuals lose up to 15% of their body weight within a year— a significant and promising outcome for those who have struggled to achieve their weight loss or blood glucose targets. Studies show that medications like semaglutide not only help lower hba1c levels in diabetes patients but also support a gradual, healthy weight loss journey, offering new hope for individuals who have faced frustration with traditional methods.

How Does Semaglutide Work?

Semaglutide, marketed under the brand names Ozempic and Wegovy, is a glucagon-like peptide-1 (GLP-1) receptor agonist that has gained significant attention for its effectiveness in managing weight and controlling blood sugar levels in individuals with type 2 diabetes. By mimicking the natural hormone GLP-1, semaglutide plays a crucial role in appetite regulation, satiety, and glucose metabolism. It functions by mimicking the action of GLP-1, a hormone produced in the intestines that is released in response to food intake. When GLP-1 is secreted, it stimulates insulin secretion from pancreatic beta cells while inhibiting glucagon release from alpha cells. This dual action helps lower blood glucose levels and improves glycemic control.

Impact on Appetite and Satiety

1. Appetite regulation: Clinical studies demonstrate that semaglutide significantly reduces appetite. For instance, a randomised controlled trial published in Diabetes Care found that participants using semaglutide experienced a 24% reduction in total energy intake compared to those on placebo. This reduction was attributed to decreased hunger and food cravings, as well as better control over eating behaviours.

2. Satiety Enhancement: Semaglutide enhances feelings of fullness after meals. In a study assessing the effects of oral semaglutide on energy intake, participants reported improved satiety scores after consuming meals, particularly after high-calorie breakfasts. The results indicated that total daily energy intake was reduced by approximately 38.9% with semaglutide compared to placebo, showcasing its effectiveness in promoting satiety.

3. Slowing Gastric Emptying: Semaglutide also slows gastric emptying, which prolongs the time food remains in the stomach. This mechanism contributes to prolonged feelings of fullness and helps prevent rapid spikes in blood sugar levels after meals.

Blood Sugar Regulation

Semaglutide's impact extends beyond appetite control; it plays a vital role in blood sugar regulation:

1. Insulin Secretion: By enhancing glucose-dependent insulin secretion, semaglutide helps maintain lower blood glucose levels during fasting and postprandial states. A clinical trial demonstrated that participants experienced an average weight loss of 5.0 kg alongside improved glycemic control after 12 weeks of treatment with semaglutide.
2. Reduction of Glucagon Levels: Semaglutide reduces glucagon secretion, which decreases hepatic glucose production. This action is particularly beneficial for individuals with type 2 diabetes who often experience elevated glucagon levels

Semaglutide for Weight Loss

Clinical trials have demonstrated its potential to lead to substantial and sustained weight reductions, making it a valuable option for those struggling with weight management.

Clinical Trials Proving the Efficacy of Semaglutide

1. STEP 1 Trial: The STEP 1 trial was pivotal in establishing the efficacy of semaglutide for weight loss. Conducted over 68 weeks, this double-blind study involved 1,961 adults with a body mass index (BMI) of 30 or greater (or ≥27 with weight-related conditions) who were assigned to receive either semaglutide (2.4 mg) or a placebo alongside lifestyle interventions. Results showed that participants receiving semaglutide experienced an average weight loss of 14.9% from baseline, compared to just 2.4% in the placebo group, representing a treatment difference of 12.4 percentage points (P<0.001).
2. SELECT Trial: The SELECT trial further evaluated semaglutide's long-term effects on weight loss in individuals without diabetes but with pre-existing cardiovascular conditions. Over a period of 208 weeks, participants treated with semaglutide experienced a mean weight reduction of 10.2%, compared to just 1.5% in the placebo group (P<0.0001). This study demonstrated that the benefits of semaglutide extend beyond short-term results, showing sustained efficacy over time.
3. Real-World Evidence: A cohort study involving 175 patients treated with semaglutide in a clinical setting reported similar outcomes to those seen in randomised trials, with an average weight loss of 5.9% at 3 months and 10.9% at 6 months. This suggests that semaglutide can be effective outside the controlled environments of clinical trials.

Factors Influencing Weight Loss

Several factors can influence the effectiveness of semaglutide in promoting weight loss:

1. Dosage: The standard dose for weight management is typically set at 2.4 mg once weekly, which has been shown to produce significant weight loss results. Higher doses may lead to increased efficacy; however, they may also heighten the risk of side effects.
2. Adherence: Adherence to the prescribed regimen is critical for achieving optimal results with semaglutide. In the STEP trials, adherence rates were high, with around 81% of participants completing the treatment protocol. Discontinuation due to side effects such as nausea and diarrhoea was noted, but many participants reported these effects as transient and manageable.

Safety and Side Effects of Semaglutide

Semaglutide therapy usually presents with certain gastrointestinal side effects, especially during the initial weeks. While these side effects can be concerning, it is important to reassure patients that they are generally mild and transient. Most individuals find that starting at a lower dose and gradually increasing it can help mitigate gastrointestinal symptoms. In fact, only about 2.9% of participants discontinued treatment due to adverse effects in clinical trials.

Common Side Effects

The most frequently reported side effects associated with semaglutide include:

1. Nausea: Nausea is the most common side effect experienced by patients taking semaglutide. In clinical trials, approximately 36.6% of participants reported nausea, particularly during the initial weeks of treatment. For example, in the STEP 1 trial, about 44% of participants receiving semaglutide experienced nausea compared to just 10% in the placebo group. Most cases are mild to moderate and typically resolve as the body adjusts to the medication.
2. Vomiting: Alongside nausea, vomiting is another common gastrointestinal side effect, affecting about 10-15% of users. This side effect is often transient and occurs more frequently during the early stages of treatment.
3. Diarrhoea: Diarrhoea is reported by approximately 8.6% of patients in clinical studies. In the STEP 5 trial, gastrointestinal adverse events were noted in 82.2% of participants taking semaglutide compared to 53.9% in the placebo group, with diarrhoea being one of the most frequently cited issues.
4. Constipation: Although less common than diarrhoea, constipation affects about 5-10% of users and can vary based on individual dietary habits.

Long-Term Safety

Concerns regarding the long-term safety of semaglutide have been addressed in several studies:

1. Overall Safety Profile: Long-term studies indicate that semaglutide is considered safe for extended use. A review highlighted that while there is a slight increase in the risk of gallbladder disease (cholelithiasis), this risk remains low (approximately 1.4% for semaglutide users compared to 1.9% for placebo). Other serious risks associated with long-term use have not been substantiated by current data.
2. Monitoring Ongoing Research: Ongoing research continues to monitor potential long-term side effects. For instance, while there have been concerns regarding pancreatitis and pancreatic cancer, studies such as those from the SUSTAIN trials have not shown a definitive link between GLP-1 receptor agonists like semaglutide and these conditions.
3. Benefits vs Risks: The benefits of semaglutide—such as improved blood sugar control and significant weight loss—often outweigh potential risks associated with its long-term use. Research indicates that maintaining treatment can lead to sustained weight loss and lower blood pressure, which are critical for reducing the risk of cardiovascular diseases.

Specific Considerations for Women

1. Pregnancy: Semaglutide is not recommended during pregnancy due to potential risks to the foetus. Animal studies have shown that semaglutide can cause thyroid tumours, and while human data are limited, the FDA advises discontinuing semaglutide at least two months prior to attempting conception. This recommendation is based on the need to ensure that any potential risks associated with the medication do not affect foetal development. The American College of Obstetricians and Gynecologists (ACOG) guidelines also emphasise that weight loss medications are not appropriate during conception or pregnancy due to the potential harm they may pose to both the mother and the unborn child.

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2. Breastfeeding: The safety of semaglutide during breastfeeding has been a topic of research. A study published in Nutrients examined eight nursing mothers using subcutaneous semaglutide and found no detectable levels of the drug in their breast milk. This suggests a minimal risk of exposure for breastfed infants. However, it is important to monitor maternal nutrition closely, as semaglutide's appetite-suppressing effects could inadvertently impact milk supply and nutritional intake necessary for both mother and child. The study highlighted that while semaglutide was not found in significant amounts in breast milk, ongoing monitoring for any gastrointestinal discomfort in infants is recommended.

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3. Hormonal Factors: Women may experience unique hormonal fluctuations throughout their life stages—such as during menstruation, pregnancy, and menopause—that can influence weight management and metabolic health. These hormonal changes can affect how women respond to medications like semaglutide. For instance, fluctuations in oestrogen and progesterone can impact appetite regulation and fat distribution, potentially altering the efficacy of weight loss treatments.

Consulting

Given the specific considerations surrounding semaglutide use in women, it is essential to consult with healthcare providers before starting this medication. A healthcare professional can provide personalised advice based on individual health profiles, including pre-existing conditions related to reproductive health or metabolic disorders. They can also help navigate potential risks associated with medication use during pregnancy or lactation.

Semaglutide and Lifestyle Changes

Semaglutide effectiveness is significantly enhanced when combined with healthy lifestyle modifications, including diet and exercise. This combination not only supports the medication's weight loss effects but also promotes overall health and well-being.

The Role of Lifestyle Modifications

1. Diet: A balanced diet is crucial for maximising the benefits of semaglutide. Clinical studies have shown that dietary changes can enhance weight loss outcomes when used in conjunction with this medication. 

Key dietary recommendations: Increase Fibre Intake

2. Exercise: Regular physical activity is a cornerstone of effective weight management and diabetes control. The NICE recommends at least 150 minutes of moderate-intensity aerobic exercise per week for individuals with type 2 diabetes.

How Semaglutide Supports Lifestyle Changes

Semaglutide aids individuals in making healthier choices by enhancing feelings of fullness and reducing appetite. This pharmacological support allows users to better adhere to dietary recommendations and engage more consistently in physical activity:

1. Appetite Suppression: By mimicking the action of GLP-1, semaglutide helps users feel satisfied with smaller portions, making it easier to stick to a balanced diet.
2. Improved Energy Levels: Many users report increased energy levels when on semaglutide, which can motivate them to engage in regular physical activity.

Conclusion

Semaglutide is a highly effective GLP-1 receptor agonist that plays a significant role in weight management and the treatment of type 2 diabetes. Clinical trials have consistently demonstrated its efficacy. However, it is essential to recognize that semaglutide is not a standalone solution. The integration of healthy lifestyle changes—including a balanced diet and regular physical activity—is crucial for maximising the benefits of this medication. Additionally, women must consider specific health factors related to pregnancy and breastfeeding when evaluating the use of semaglutide.

Before starting semaglutide or any weight loss medication, consulting with a healthcare provider is vital. A healthcare professional can provide personalised guidance based on individual health profiles, helping patients make informed decisions about their treatment options.

While semaglutide offers promising results for weight loss and metabolic health, the best outcomes are achieved through a comprehensive approach that includes medical intervention and lifestyle modifications. By working closely with healthcare providers, individuals can develop effective strategies tailored to their unique needs and goals.

Frequently Asked Questions

1. What exactly is semaglutide?
Semaglutide is a peptide medication classified as a GLP-1 receptor agonist. It works by mimicking a natural hormone in the body that helps regulate blood sugar and appetite, making it beneficial for diabetes management and weight loss.

2. How does semaglutide assist with weight loss?
Semaglutide activates GLP-1 receptors that play a role in appetite control and digestion. By reducing hunger and increasing feelings of fullness, it supports sustainable weight loss over time.

3. Is semaglutide only for those with diabetes?
No, semaglutide is also approved for use as a weight loss medication, even for people without diabetes. The brand name Wegovy is commonly prescribed specifically for weight management in non-diabetic individuals.

4. How soon can I expect to see results with semaglutide?
Results can vary, but some individuals notice changes in appetite and weight within the first few weeks. Full benefits, however, often take several months with consistent use.

5. What are the possible side effects of semaglutide?
Common side effects include nausea, vomiting, and digestive discomfort, especially at the start. These effects are generally manageable, and your healthcare provider can offer tips to minimize them.

References

1. Blundell, J., Finlayson, G., Axelsen, M., Flint, A., Gibbons, C., Kvist, T., & Hjerpsted, J. B. (2021). Effects of semaglutide on appetite control, ad libitum energy intake, and food preference in subjects with obesity. Diabetes, Obesity and Metabolism, 23(2), 135–144. https://doi.org/10.1111/dom.14209‍
2. Guo, J., Chen, Y., Zhang, X., & Liu, A. (2022). Mechanisms of action of glucagon-like peptide-1 receptor agonists in body weight regulation and potential application in obesity treatment. Frontiers in Endocrinology, 13, 9486455. https://doi.org/10.3389/fendo.2022.9486455‍
3. Wilding, J. P. H., Batterham, R. L., Calanna, S., Davies, M., Van Gaal, L. F., Lingvay, I., McGowan, B. M., Rosenstock, J., Tran, M. T., Wadden, T. A., Wharton, S., Yokote, K., Zeuthen, N., & Kushner, R. F. (2023). Effects of tirzepatide versus semaglutide on weight reduction in individuals with obesity: A randomised controlled trial. The New England Journal of Medicine, 389(6), 503-515. https://doi.org/10.1056/NEJMoa230756‍
4. Iepsen, E. W., Lundgren, J., Holst, J. J., Madsbad, S., & Torekov, S. S. (2021). Semaglutide-induced weight loss in patients with obesity. Diabetes, Obesity and Metabolism, 23(2), 155-161. https://doi.org/10.1111/dom.14232‍
5. National Institute for Health and Care Excellence. (n.d.). Physical activity. NICE. https://www.nice.org.uk/guidance/qs84‍
6. Lundgren, J. R., Janus, C., Jensen, S. B., Pedersen, O., Juhl, C. R., Christensen, R., Holst, J. J., & Torekov, S. S. (2021). The efficacy of semaglutide in patients with obesity: A systematic review and meta-analysis. Diabetes, Obesity and Metabolism, 23(3), 747-755. https://doi.org/10.1111/dom.14218‍
7. Ross, K., Dennis, S., & Macdonald, J. (2022). Healthcare professionals’ perspective on delivering personalised and holistic care: Using the theoretical domains framework. BMC Health Services Research, 22, 1278. https://doi.org/10.1186/s12913-022-08934-7

Starting a new weight loss treatment can feel like a breakthrough - especially for women who have spent years struggling with PCOS, irregular cycles, or stubborn weight gain. Many people using GLP-1 medication describe renewed energy, steady progress on the scale, and a sense of hope. But alongside these benefits, some also notice unexpected changes in their menstrual cycle - such as new cramping, spotting, or shifts in flow.

It’s natural to wonder: Is this normal? Is it the medication, or just my body adjusting?

If you’ve had similar questions, you’re not alone. As more women turn to Mounjaro for weight management or type 2 diabetes, new conversations are opening up about its impact on menstrual health.

Changes in your cycle can feel unsettling, particularly when they appear alongside a new treatment. Whether it’s lighter or heavier bleeding, unfamiliar cramps, or questions about how Mounjaro may interact with hormones, contraception, or PCOS, it’s important to have clear, UK-specific information.

In this blog, we’ll explore how Mounjaro may affect the menstrual cycle, and share practical ways to manage symptoms and stay informed - so you can feel supported, not confused, as you move forward on your health journey.

The Hormonal Connection: How Mounjaro Might Influence Menstrual Cycles

Mounjaro works by mimicking two naturally occurring gut hormones - GLP-1 (glucagon-like peptide-1) and GIP (glucose-dependent insulinotropic polypeptide). Together, these hormones help to slow down gastric emptying, reduce appetite, improve insulin sensitivity, and lower blood glucose levels. While these effects are primarily targeted at metabolic regulation and weight loss, they also have indirect impacts on the hormonal systems that control the menstrual cycle. 

For women, especially those with underlying hormonal conditions like polycystic ovary syndrome (PCOS), even small shifts in insulin levels, body weight, or inflammation can have a ripple effect on oestrogen balance, ovulation patterns, and menstrual symptoms. This means that although Mounjaro is not designed to act on reproductive hormones, its metabolic actions can influence menstrual health in meaningful ways.

Indirect Effects via Weight Loss

1. Weight and Hormones

One of the most significant ways Mounjaro may influence the menstrual cycle is through weight loss, which has a profound effect on hormonal balance. Body fat is not just stored energy, it’s hormonally active. Excess adipose tissue increases the production of oestrogen through a process called aromatisation. 

When oestrogen levels are too high, it can disrupt the delicate hormonal interplay that governs the menstrual cycle, leading to irregular or absent periods, heavy bleeding, and painful cramps. By promoting steady and sustained weight loss, Mounjaro can help rebalance oestrogen levels, restoring hormonal equilibrium and contributing to more predictable menstrual patterns.

2. Benefits of Weight Loss on Menstrual Health

In addition to regulating oestrogen, healthy weight loss brings broader benefits to menstrual health. Studies have shown that losing weight can lead to more regular cycles, a reduction in PMS symptoms, and a decrease in systemic inflammation, which is a known contributor to period pain. Weight loss also significantly improves insulin sensitivity, a crucial factor for women with PCOS.

A 2025 clinical study in women with PCOS and obesity (n=56) found tirzepatide led to significant weight reduction (mean 9.54%) and improvement in menstrual regularity: irregular cycles decreased from 85.7% before treatment to 32.1% after. There was also a notable drop in prevalence of ovarian cysts and insulin resistance

PCOS-Specific Considerations

For those living with PCOS - a condition that affects up to 1 in 10 women in the UK - Mounjaro’s impact can be particularly positive. By improving insulin resistance, one of the root causes of PCOS, Mounjaro can help restore more regular ovulation, reduce elevated androgen levels (which cause symptoms like acne, excess facial hair, and scalp hair thinning), and potentially enhance fertility. While not licensed specifically for PCOS in the UK, Mounjaro’s metabolic benefits can offer meaningful hormonal improvements for many women living with this condition.

Based on survey data from 1,754 users of GLP-1 medications (including tirzepatide) showed that 27% noticed changes in their menstrual cycles after starting treatment. Respondents with PCOS were even more likely to report changes (43%), with the most common being more predictable, more frequent, or shorter periods. However, rigorous clinical trial data specifically for tirzepatide remain limited

Direct Effects? What the Evidence Says

Despite anecdotal reports, there’s limited clinical trial data on Mounjaro’s direct impact on menstruation. Current studies haven’t flagged menstrual changes or cramps as common side effects. The MHRA and manufacturer’s patient information leaflets for Mounjaro in the UK do not list period changes as a primary or expected adverse effect.

However, real-world experiences from patients on forums and social media have started highlighting menstrual irregularities, delayed periods, or changes in cramp severity - pointing to a potential area for future research.

Mounjaro and Period Cramps: Perspectives and Patient Experiences

What Are Women Reporting?

Although formal studies are currently limited, many women taking Mounjaro have shared a range of personal experiences on social media related to their menstrual cycle. Some report that their periods have become lighter and less painful, while others have noticed delayed cycles, spotting, or even more intense cramps during the initial adjustment phase. These changes may not be due to the medication directly, but rather indirect effects of weight loss, which can influence hormonal balance. 

Fluctuations in oestrogen, insulin, and leptin levels - all of which are sensitive to changes in body weight and metabolic health - could contribute to these menstrual changes. Additionally, some of the side effects commonly associated with Mounjaro, such as nausea or abdominal discomfort, may overlap with or intensify typical menstrual symptoms, making it harder to distinguish the cause.

Potential Reasons for Improvement in Cramps

1. Reduced Inflammation

Mounjaro-induced weight loss can lower systemic inflammation - a major driver of dysmenorrhoea (painful periods).

2. Hormonal Regulation

Stabilising insulin and oestrogen levels may help with:

• Less uterine muscle hyperstimulation
  
  
• Fewer prostaglandin surges (compounds linked to cramping)

Could Mounjaro Make Cramps Worse?

While many women experience improvements in their menstrual symptoms with Mounjaro, it’s also possible for some to notice a temporary worsening of cramps or cycle disturbances. This can happen for several reasons. Rapid weight loss, especially in the early stages of treatment, can place stress on the body and temporarily disrupt hormonal balance, leading to more intense cramps or irregular periods. Additionally, as the body undergoes hormonal fluctuations during weight loss, menstrual cycles may become less predictable for a time.

Another important factor to consider is that Mounjaro slows gastric emptying, which may affect how oral medications are absorbed - including combined oral contraceptive pills and oral HRT. If the absorption of these hormones is reduced, hormone levels in the body may drop, potentially causing breakthrough bleeding, spotting, or a return of menstrual symptoms such as cramping or irregular flow. This is particularly relevant for women who rely on these medications for menstrual regulation or symptom control and highlights the importance of discussing contraceptive or HRT options with a healthcare provider when starting Mounjaro.

Gastrointestinal Side Effects and Menstrual Discomfort

Mounjaro can cause:

• Nausea
  
  
• Constipation
  
  
• Diarrhoea
  
  
• Abdominal discomfort

These may overlap with PMS symptoms, making it harder to distinguish between side effects and menstrual pain.

Important Considerations for Users on Mounjaro

1. Contraception and Mounjaro

For women using Mounjaro, there are several important factors to consider when it comes to menstrual health, contraception, and hormone therapy. One of the key concerns is how Mounjaro may affect the absorption of oral medications due to its action of slowing gastric emptying. This can potentially reduce the effectiveness of oral contraceptive pills, putting users at risk of unintended pregnancy.

Current guidance suggests using a barrier method, such as condoms, for at least four weeks after starting Mounjaro and for four weeks after each dose increase. Alternatively, women may wish to speak to their GP about switching to non-oral forms of contraception, such as patches, IUDs, or implants, which are not affected by changes in digestion.

NHS and Manufacturer Recommendations:

• Use a barrier method (like condoms) for at least 4 weeks after starting Mounjaro
  
  
• Also apply the 4-week barrier rule after each dose increase
  
  
• Consider switching to non-oral forms of contraception (e.g., patch, IUD, implant)

2. Hormone Replacement Therapy (HRT)

Women taking hormone replacement therapy (HRT) during the perimenopausal or menopausal period should be aware that oral HRT may also be impacted. The British Menopause Society advises considering transdermal options, like patches or gels, which bypass the digestive system and maintain more stable hormone levels. In some cases, adjusting the dose of oral progesterone may be necessary, but this should only be done in consultation with a healthcare provider.

3. Track Your Cycle

Tracking your menstrual cycle becomes particularly important while on Mounjaro. Noting changes in cycle length, flow, cramping, mood swings, or energy levels can help identify any emerging patterns or concerns. You should seek medical advice if you experience significant changes, such as missed periods, unusually heavy or light bleeding, persistent or worsening cramps, or unexpected spotting - especially if you're on HRT or haven’t had periods for some time. These could signal hormonal imbalances, medication side effects, or other underlying issues that need attention. Use apps like Clue or Flo, or simply note symptoms in a calendar.

Managing Menstrual Symptoms While on Mounjaro

Managing menstrual symptoms while on Mounjaro involves a holistic approach that supports both hormonal balance and overall wellbeing. 

1. Supportive Lifestyle Habits

Start by focusing on lifestyle habits that naturally ease period discomfort. A balanced diet rich in whole grains, leafy greens, lean proteins, and healthy fats can help stabilise blood sugar levels and reduce inflammation - both of which may play a role in period cramps and mood changes. Including foods high in magnesium (like nuts, seeds, and dark chocolate) and omega-3 fatty acids (like salmon or flaxseeds) may also help reduce cramping.

Staying physically active is another powerful tool - gentle exercises like walking, stretching, or yoga can increase blood flow, reduce tension, and improve your overall sense of wellbeing during your cycle. Hydration and adequate sleep support hormone regulation and can ease fatigue and bloating, while stress-reducing activities like meditation, journaling, or even warm baths may help ease both mental and physical premenstrual symptoms.

2. Pain Relief Options

For pain relief, over-the-counter medications such as paracetamol or ibuprofen can be effective in managing cramps. However, it’s important to use them cautiously if you’re experiencing gastrointestinal side effects from Mounjaro like nausea or constipation. 

3. Complementary Therapies

Some people also find comfort in non-pharmacological methods like applying a hot water bottle to the lower abdomen, using herbal teas like chamomile or ginger, or taking magnesium supplements - though any supplement should be discussed with your GP to ensure it's safe alongside your current medications.

4. Communicate with Your Healthcare Provider

Lastly, open communication with your healthcare provider is essential. If your cycle becomes irregular, if cramps worsen, or if you experience any unexpected symptoms such as spotting, prolonged bleeding, or missed periods, it’s important to seek professional advice. Your doctor can help determine whether these changes are related to Mounjaro, weight loss, hormonal shifts, or another underlying cause, and guide you on the best course of action.

Conclusion

Mounjaro is a powerful medication with proven benefits for weight loss and metabolic health. For many women, these benefits may translate into more regular and less painful periods, especially for those with PCOS or insulin resistance. However, it’s essential to understand that period changes are not officially listed as side effects but do occur anecdotally. Menstrual cramps may improve or worsen depending on your hormonal baseline and weight loss pace. Mounjaro can affect hormonal contraceptives and HRT absorption, which requires additional precautions. Being proactive, tracking your cycle, choosing the right contraceptives, and staying in touch with your GP, ensures that you can reap the benefits of Mounjaro without sacrificing menstrual health.

Weight loss journeys are about more than numbers on a scale. For women, especially, they often involve complex hormonal shifts. 

References

• Natural Cycles. (2024). Do GLP-1 weight loss drugs affect the menstrual cycle? [online] Available at: https://www.naturalcycles.com/research-library/do-glp-1-weight-loss-drugs-affect-the-menstrual-cycle [Accessed 15 Jul. 2025].
• National Center for Biotechnology Information (NCBI). (2022). Physiology, Estrogen. [online] In: StatPearls. Available at: https://www.ncbi.nlm.nih.gov/books/NBK585056/ [Accessed 15 Jul. 2025].
• Simple Online Pharmacy. (2024). Can Mounjaro affect your period? [online] Available at: https://www.simpleonlinepharmacy.co.uk/health-advice/weight-loss/mounjaro/can-mounjaro-affect-period/ [Accessed 15 Jul. 2025].
• Lal, M., Kumari, M. and Verma, S. (2025). Impact of GLP-1 Receptor Agonists on Menstrual Health in Women with Obesity and PCOS. International Journal of Diabetes and Endocrinology, 10(2), pp.43–47. https://doi.org/10.11648/j.ijde.20251002.12
• Medicines and Healthcare products Regulatory Agency (MHRA). (2023). MHRA authorises diabetes drug Mounjaro (tirzepatide) for weight management and weight loss. [online] GOV.UK. Available at: https://www.gov.uk/government/news/mhra-authorises-diabetes-drug-mounjaro-tirzepatide-for-weight-management-and-weight-loss [Accessed 15 Jul. 2025].