The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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gradual weight management After Giving Birth: UK Options
Losing weight after pregnancy is a common concern for many new mothers in the UK. While some weight loss happens naturally in the weeks following birth, rapid or persistent weight gain can be frustrating. If you're struggling with postpartum weight management, there are several evidence-based options available, including prescription weight management medications for eligible adults. This guide covers safe approaches and where to find NHS support or private alternatives.
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Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
UK Prescription Weight Management Options
If you're looking for weight management support in the UK, prescription medications are available for eligible adults through both NHS and private prescribing. The three main options are Mounjaro (tirzepatide), Wegovy (semaglutide), and Saxenda (liraglutide).
Eligibility: You may be eligible if you have a BMI of 30 or above, or 27–29.9 with weight-related health conditions such as high blood pressure or prediabetes. For mothers of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds apply. All prescription weight loss medications work alongside reduced-calorie diet and increased physical activity — they are not replacements for lifestyle changes.
How they work: Mounjaro and Wegovy are once-weekly injections that work on appetite-regulating hormones. In clinical trials, Mounjaro helped participants lose an average of 15–21% of body weight, whilst Wegovy showed similar results around 14.9%. Individual results vary significantly. Your GP or a licensed prescriber will assess whether these are suitable for you, considering your medical history and any contraindications (including if you're breastfeeding).
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS Access vs Private Options
In the UK, prescription weight loss medication is available through two routes. NHS access: Referral to a specialist tier 3 weight management service, typically through your GP. However, NHS availability varies by region and waiting lists can be lengthy. Private access: Available through GPhC-registered online pharmacies following a clinical assessment with a UK-licensed prescriber — no NHS referral needed.
Start by speaking to your GP about your weight management goals. They can assess your eligibility, discuss whether prescription medication is appropriate, and consider any postpartum-specific factors (including breastfeeding status). Use our free BMI calculator to check your current BMI before your appointment, and our GLP-1 weight loss calculator to explore potential outcomes with medication if your GP recommends it.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Is it safe to take weight loss medication while breastfeeding?
No — prescription weight loss medications including Mounjaro and Wegovy are not recommended during breastfeeding. You should discuss timing with your GP. If you're bottle feeding, medication becomes an option after clinical assessment. Always inform your prescriber of your feeding method.
How much weight can I expect to lose after giving birth naturally?
Most women lose approximately 5–7 kg in the first two weeks after birth (baby, placenta, fluids). A further 3–5 kg typically disappears in the following weeks. gradual weight management beyond this usually requires dietary changes and physical activity — prescription medication is an option for eligible adults.
When can I start weight loss medication after pregnancy?
There is no fixed timeline — it depends on your individual circumstances, breastfeeding status, and health. Discuss with your GP before starting any weight loss treatment. They'll assess when it's appropriate and safe for you specifically.
What does the NHS recommend for postpartum weight management?
The NHS recommends gradual weight loss of 0.5–1 kg per week through healthy eating and increased physical activity. gradual weight management is not recommended postpartum, particularly if breastfeeding. Your GP can refer you to tier 1 or tier 2 weight management support initially.
Are prescription weight loss injections the only option?
No. Prescription medication is one option for eligible adults. The NHS also offers diet advice, exercise programmes, and behavioural support through GP practices and community services. Your GP can discuss all options and what suits your circumstances.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.