Progesterone Does Not Help With Bloating—It Actually Causes It
Progesterone is a known cause of bloating, not a treatment for it. The hormone slows gastrointestinal motility and can lead to abdominal distension, making bloating worse rather than better.
Why Progesterone Causes Bloating
Mechanism of Gastrointestinal Effects
- Progesterone slows GI motility throughout the digestive tract, leading to delayed gastric emptying and constipation 1
- The hormone has an inhibitory effect on both gastric and small bowel motility, which directly contributes to feelings of abdominal fullness and bloating 1
- During pregnancy, increased progesterone levels are specifically identified as a cause of constipation, which in turn worsens bloating 1
Direct Evidence of Bloating as a Side Effect
The FDA drug label for oral progesterone explicitly lists "abdominal bloating" and "abdominal distention" as common adverse effects 2:
- In clinical trials, 12% of women taking progesterone 200 mg experienced abdominal bloating compared to only 5% on placebo 2
- In another trial using progesterone 400 mg daily, 8% reported abdominal distention (bloating) 2
- These effects are dose-dependent and occur across different formulations 2
Additional Gastrointestinal Side Effects
Beyond bloating, progesterone causes multiple GI symptoms that compound the problem:
- Nausea and vomiting (8% vs 0% placebo in one trial) 2
- Constipation due to slowed intestinal transit 1, 2
- Abdominal pain and cramping (20% in clinical trials) 2
Clinical Context: When Bloating Occurs with Progesterone Use
Pregnancy-Related Bloating
- Excessive fiber intake combined with osmotic laxatives like lactulose (used to treat progesterone-induced constipation) can cause maternal bloating 1
- This creates a problematic cycle where treating progesterone's constipation effects may worsen bloating 1
Hormone Replacement Therapy
- Women taking progesterone for endometrial protection during estrogen therapy commonly report bloating as a side effect 2
- The symptom is significant enough to affect treatment adherence 2
Common Pitfalls to Avoid
Do not prescribe progesterone to treat bloating under any circumstances. The evidence uniformly shows it worsens this symptom through multiple mechanisms:
- Slowed GI motility 1
- Direct adverse effect documented in FDA labeling 2
- Constipation leading to secondary bloating 1
If a patient is experiencing bloating while on progesterone therapy (for legitimate indications like preterm birth prevention or endometrial protection), consider: