Hormones & Mood.
The Brain Connection.

The onset of regular cyclical hormones at puberty dramatically increases risk of depression and anxiety — particularly in girls — compared to pre-pubertal peers. This is not solely psychosocial: the new oestrogen and progesterone fluctuations are genuinely destabilising for some adolescent brains. First-onset PMS and anxiety often begin here.

Oestrogen and progesterone rise to levels 100x higher than normal during pregnancy. Many women experience improved mood in the second trimester as oestrogen stabilises. First and third trimesters can be challenging — anxiety, mood swings and prenatal depression are common and underdiagnosed. Antenatal depression affects up to 10–15% of South African women.

At delivery, oestrogen and progesterone fall from their highest-ever levels to near zero within 24–48 hours — the most dramatic hormonal drop the body experiences at any point in life. Baby blues (days 3–5, self-resolving) affect up to 80% of women. Postnatal depression (PND) — lasting weeks to months — affects 10–15% in SA and requires treatment. Postpartum psychosis (rare, <0.2%) is a psychiatric emergency.

Perimenopause is associated with a two-to-fourfold increased risk of first-episode clinical depression — even in women with no prior mental health history. Erratic oestrogen fluctuations (rather than simply low oestrogen) are particularly destabilising neurochemically. This is often misdiagnosed as primary depression and treated with antidepressants alone — when oestrogen via HRT addresses the root hormonal driver.

Once the hormonal fluctuations of perimenopause cease and oestrogen stabilises at a new (lower) level, mood often improves for many women. However, those with ongoing low oestrogen, poor sleep from ongoing vasomotor symptoms, or unaddressed genitourinary changes may continue to struggle. HRT remains the most effective treatment for oestrogen-driven mood changes in this phase.

Track mood daily alongside cycle data for 2–3 months. Apps: Clue, Flo, Natural Cycles. Validated tool: DRSP (Daily Record of Severity of Problems). Understanding your personal pattern is diagnostic and empowering — it also enables proactive coping strategies.

Sleep (7–9 hours, consistent schedule), aerobic exercise (150+ min/week, especially in luteal phase), blood sugar stability (protein at every meal, minimal refined sugar), alcohol reduction (worsens mood dysregulation) and stress management are all evidence-based and meaningfully reduce cyclical mood symptoms.

Transdermal oestradiol is highly effective for perimenopausal mood changes and is often superior to antidepressants in this context — because it addresses the hormonal root cause. The British Menopause Society and NICE both recommend considering oestrogen before antidepressants for perimenopausal mood symptoms in women without a prior history of clinical depression.

SSRIs are first-line for PMDD-severity cyclical mood symptoms and can be taken continuously or only in the luteal phase. Also appropriate for postnatal depression and comorbid anxiety. Work best when the underlying cycle-mood pattern has been clearly established.

Cognitive Behavioural Therapy adapted for cyclical mood patterns teaches women to recognise, predict and reframe symptoms. Reduces catastrophising during the luteal low and builds coping strategies for predictable difficult periods. Evidence supports CBT as both an adjunct and standalone treatment for mild-moderate PMS/PMDD and perimenopausal mood changes.