Weight loss medicine and PCOS: what women should know

Key takeaways

• A large Indian study found PCOS in 7.2% to 19.6% of women aged 18 to 40, depending on the diagnostic criteria used.
• Up to 75% of women with PCOS and overweight have insulin resistance, which makes weight harder to lose.
• A 2024 review for the international PCOS guideline found GLP-1 medicines appeared better than placebo for weight and waist, but trials in PCOS are few.
• Weight loss can restore ovulation, so pregnancy can happen sooner than expected; contraception matters.
• Tirzepatide can reduce the reliability of the oral pill for some weeks; semaglutide needs stopping at least two months before trying to conceive.

How are PCOS and weight connected?

Many young women with PCOS tell me they have "tried everything" and the weight still won't move. I believe them. With PCOS, the biology really is working against you, so let me explain why.

Polycystic ovary syndrome is a hormonal condition that can cause irregular periods, acne, excess facial or body hair, scalp hair thinning and difficulty conceiving. It is common in India. A multicentre study of nearly 9,000 women, published in JAMA Network Open in 2024, found a prevalence of 7.2% to 19.6% depending on the criteria, with higher rates in urban areas. Around a quarter of women with PCOS in that study had metabolic syndrome.

See, what happens is, insulin resistance sits at the centre of the weight problem. An NHS hospital leaflet notes that about 30% of slim women with PCOS have insulin resistance, rising to as many as 75% of women who are overweight. High insulin drives the ovaries to make more androgens and makes the body store fat, especially around the waist. It becomes a cycle: weight worsens PCOS, and PCOS makes weight harder to lose.

What does weight loss do for PCOS?

The same leaflet notes that losing as little as 5% of body weight can:

• make periods more regular and more often ovulatory;
• lower insulin levels;
• reduce heart disease risk over time;
• lighten heavy periods caused by extra estrogen from fat tissue.

For an 80 kg woman, 5% is 4 kg. Women with PCOS are also about three times as likely to develop type 2 diabetes, and long gaps between periods raise the risk of endometrial problems, so the benefits go well beyond appearance.

What does the evidence say about GLP-1 medicines in PCOS?

Honestly: promising, but thin. A 2024 systematic review in Obesity Reviews, written to inform the 2023 international evidence-based PCOS guideline, included 11 trials of anti-obesity medicines in women with PCOS. Liraglutide and semaglutide appeared better than placebo for weight, BMI and waist, while an older GLP-1 medicine performed similarly to metformin on most outcomes. The authors concluded that published data in PCOS are very limited.

What this means in practice:

Metformin, an insulin-sensitising tablet, remains widely used in PCOS. It does not cause low sugar on its own and may help weight, periods and androgen levels modestly. The choice between options, or a combination, depends on your goals, tests and pregnancy plans. I lay out the options; you choose.

What about contraception and pregnancy?

That is very important to understand, because PCOS creates a specific trap. Many women with PCOS assume they cannot conceive easily. As weight falls, ovulation can return, sometimes before periods look regular. Pregnancy can then happen unexpectedly while on a medicine that should not be used in pregnancy.

Key points from UK guidance:

• Semaglutide: the NHS advises stopping at least two months before trying for a baby. Contraception is needed while on it. The UK Faculty of Sexual and Reproductive Healthcare (FSRH) does not expect it to reduce the effectiveness of the oral pill.
• Tirzepatide: the FSRH advises women on an oral contraceptive to switch to a non-oral method or add a barrier method for four weeks after starting and for four weeks after each dose increase, because it may reduce pill absorption. It advises stopping at least one month before a planned pregnancy.
• Vomiting or diarrhoea: if these happen within a few hours of taking the pill, missed-pill rules apply.

If you are planning a pregnancy in the next year, let us discuss timing before starting. A gynaecologist should be part of that conversation.

What else belongs in a PCOS weight plan?

• Protein at each meal to support fullness and muscle; see my Indian vegetarian protein guide.
• Strength training two or three times a week, which improves insulin sensitivity; see why strength training matters.
• Sleep and stress. Late nights and irregular meals, common for young professionals in Mumbai, worsen insulin resistance.
• Regular periods. If cycles are very irregular, a doctor may suggest a way to ensure a bleed at least every three months to protect the womb lining.
• Screening for prediabetes, cholesterol and fatty liver; see weight loss medicine, prediabetes and type 2 diabetes.
• Hair and skin. PCOS-related scalp thinning or acne may need its own treatment alongside weight loss.

How I approach this at Dr Tvacha

In The Endgame Weight Programme, I review your PCOS history, cycles, contraception and pregnancy plans before any prescription, starting with a Rs 499 video eligibility consult. Where fertility planning is involved, Dr Anagha Karkhanis, Gynaecologist and Fertility Specialist, consults at Cocoon × Dr Tvacha in Thane, one floor above Dr Tvacha Thane. PCOS hair thinning can be assessed through our hair programme.

Written by

Dr Amit KarkhanisAesthetic Physician · MBBS, Dip. Dermatology (UK) · Reg. No. 2001/02/1124

Founder of Dr Tvacha, practising in Thane since 2005. Leads the weight loss and hair programmes.