Can Low Progesterone Cause Hot Flashes and Crankiness?
Low progesterone levels are associated with hot flashes and mood symptoms including irritability and fatigue, though the relationship is complex and context-dependent. 1, 2, 3
Hot Flashes and Progesterone
Progesterone deficiency contributes to vasomotor symptoms (hot flashes), and progesterone supplementation effectively reduces these symptoms. 1, 2
- Oral micronized progesterone (300 mg at bedtime) produces a 55% reduction in hot flashes and night sweats in menopausal women over 3 months 2
- Progesterone levels fall during the menopausal transition, and this decline is associated with the onset of vasomotor symptoms 1
- The mechanism appears related to progesterone's direct effects on thermoregulation rather than solely through estrogen modulation 2
Important caveat: Hot flashes are primarily driven by low estrogen levels rather than progesterone alone. 4 Following bilateral oophorectomy, over 90% of women experience hot flashes due to the sudden drop in both estrogen and progesterone 4. The evidence suggests that while progesterone supplementation helps, estrogen withdrawal is the dominant factor in most menopausal hot flash scenarios 4.
Mood Symptoms and Progesterone
Low progesterone levels are specifically associated with increased irritability, aggressive behavior, and fatigue—symptoms that align with "crankiness." 3
- Women with higher luteal-phase progesterone levels consistently demonstrate lower levels of premenstrual aggressive behavior and fatigue compared to those with low progesterone 3
- The relationship is dose-dependent: maximal progesterone values during the luteal phase correlate negatively with aggression/irritability and fatigue scores 3
- Progesterone supplementation (300 mg daily) does not cause depression and may improve mood stability 2
Critical distinction: The evidence suggests that progesterone fluctuations and withdrawal may be more problematic than absolute low levels. 5 Women appear differentially sensitive to mood-destabilizing effects of changes in gonadal steroids, with some individuals being particularly vulnerable to hormone fluctuations 5. This means that unstable progesterone levels may cause more mood symptoms than consistently low levels in some women 5.
Clinical Context and Mechanisms
The interaction between estrogen and progesterone levels matters more than progesterone alone. 6
- In women with premenstrual dysphoric disorder, the interaction between early luteal-phase estrogen and progesterone levels predicts symptom severity 6
- Low early-phase estrogen appears to moderate the provoking effect of progesterone on mood symptoms 6
- This suggests that progesterone's effects on mood depend heavily on the hormonal milieu, not just absolute progesterone levels 6
Postpartum Evidence
Postpartum studies provide mixed evidence for progesterone's role in mood symptoms. 4
- Progesterone levels within 12-48 hours after birth were inversely related to depression symptoms at 6 months postpartum in one study of 54 mothers 4
- However, three other small studies found no link between progesterone levels and concurrent depression symptoms between 1-17 weeks postpartum 4
- Late-pregnancy progesterone levels and the magnitude of perinatal progesterone drop did not predict postpartum depression symptoms 4
This suggests that acute progesterone changes may have different effects than chronic low levels, and individual vulnerability factors play a significant role. 4
Common Pitfalls
- Do not assume all mood symptoms are progesterone-related: Estrogen deficiency, thyroid dysfunction, and psychosocial factors frequently coexist and may be the primary drivers 4
- Avoid attributing symptoms to progesterone without measuring levels: Mid-luteal phase progesterone levels below 6 nmol/L indicate anovulation and true progesterone deficiency 4
- Consider the clinical context: Progesterone's effects differ in premenopausal women with cycling hormones versus menopausal women with sustained deficiency 1, 3