Will I experience more weight gain with progesterone-only pills (POP) or combined oral contraceptives (COC)?

Weight Gain with Progesterone-Only Pills vs Combined Oral Contraceptives

Progesterone-only pills (POPs) are more likely to cause weight gain than combined oral contraceptives (COCs), particularly in individuals who are early weight gainers. 1

Evidence on Weight Gain with Different Contraceptive Methods

Progesterone-Only Pills (POPs)

• A Cochrane review demonstrated evidence of weight gain associated with progestin-only contraceptives, particularly with depot medroxyprogesterone acetate (DMPA) 1
• Studies show that DMPA users experience more weight gain compared to users of combined oral contraceptives and non-hormonal contraception 2
• Early weight gainers (those who gain >5% of body weight at 6 months) on DMPA may experience significant weight increases, with a mean BMI increase of 7.6 over 18 months compared to 2.3 for non-early gainers 1

Combined Oral Contraceptives (COCs)

• There is no clear evidence of weight change associated with combination oral contraceptive pills 1
• A Cochrane review found that available evidence does not support a causal association between COCs and weight gain 3
• Studies show that the mean weight at the end of four cycles of triphasic OC use was the same as baseline weight (average weight change, 0.0 pounds) 4
• 72% of women had either no weight change or a weight loss with COC use 4

Weight Fluctuations with Contraceptive Use

• During COC use, weight fluctuates by about 3 kg over an observation interval from 6 to 24 months 5
• With COCs, regular but minor weight shifts may occur during each menstrual cycle, with mean weight rising by one-half pound (0.2 kg) during the first weeks of each cycle and falling by the same amount during the last few days 4
• The age-associated weight gain has been described to be approximately 300 g/year in the general female population 5

Factors Affecting Weight Gain with Contraceptives

• Different progestins have variable androgenic/anti-androgenic profiles, which may influence weight changes 1, 6
• Individual factors play a significant role in weight response to hormonal contraceptives
• Early weight gain (within first 6 months) may predict continued weight gain with ongoing use, particularly with DMPA 1

Monitoring and Management

• Baseline weight and BMI measurement might be useful for monitoring contraceptive users over time 1
• For those concerned about weight gain, consider:
  1. Starting with a COC containing 30-35 μg of ethinyl estradiol and a progestin such as levonorgestrel or norgestimate 1
  2. Monitoring weight at follow-up visits, particularly at 1-3 months after initiation 1
  3. Considering a copper IUD as a hormone-free alternative if weight gain becomes problematic 6

Counseling Points

• Weight gain is often perceived as a side effect of hormonal contraceptives but is not consistently supported by evidence for COCs
• Patients should be counseled about typical weight fluctuations to reduce discontinuation due to perceptions of weight gain
• Regular weight-bearing exercise and healthy diet should be encouraged for all contraceptive users

In conclusion, while individual responses vary, the evidence suggests that progesterone-only methods, particularly DMPA, are more likely to cause weight gain than combined oral contraceptives. For patients particularly concerned about weight gain, COCs would be the preferred choice between these two options.