Many women come to my practice in their 40s saying some version of the same thing: I don't feel like myself. They're more irritable than they used to be. Anxiety shows up out of nowhere. Sleep is unreliable, focus feels scattered, and the resilience they've always counted on seems thinner.
Often, no one has mentioned perimenopause. Their periods may still be fairly regular, and hot flashes may not have started. But the hormonal transition is already underway, and for many women the emotional symptoms arrive first.
What is perimenopause?
Perimenopause is the transition leading up to menopause, which is defined as 12 consecutive months without a period. It most often begins in the 40s, sometimes earlier, and lasts about four years on average, though it can be considerably longer.
What defines this stage is fluctuation in hormones, not simply declining hormones. Estrogen can swing higher and lower than usual from month to month, sometimes week to week. Progesterone declines as ovulation becomes less consistent. This fluctuation, more than any single hormone level, appears to drive many of the symptoms.
Why hormones affect mood:
Estrogen and progesterone do far more than regulate the menstrual cycle. Both act directly in the brain. Estrogen influences serotonin, norepinephrine, and dopamine, which are the monoamine neurotransmitters involved in mood, motivation, and focus. It also supports sleep regulation and the brain's stress response. Progesterone is converted into allopregnanolone, a neurosteroid that acts on GABA receptors, which are the brain's main calming system.
When these hormones fluctuate unpredictably, the systems that keep mood and stress tolerance steady can become less stable. Some women are more sensitive to these shifts than others, which helps explain why perimenopause is easy for one person and destabilizing for another.
The emotional symptoms:
Emotional changes during perimenopause are common and real. They can include:
Irritability or anger that feels out of proportion or out of character
New or worsening anxiety, including racing thoughts, restlessness, or a sense of dread
Low mood, tearfulness, or loss of interest in things you usually enjoy
Mood swings that feel harder to predict or control
Brain fog, including forgetfulness, word-finding trouble, and difficulty concentrating
Lower stress tolerance, where ordinary demands feel heavier than they used to
Sleep disruption, which often worsens every other symptom on this list
Physical symptoms often travel alongside these: hot flashes, night sweats, changes in cycle length or flow, fatigue, joint aches, and changes in libido. Night sweats in particular can fragment sleep in ways that feed directly into mood and anxiety.
When it becomes depression:
Research, including the large Study of Women's Health Across the Nation (SWAN), has found that the risk of depression rises during perimenopause, even among women with no prior history. The risk is higher for women who have experienced depression before, premenstrual dysphoric disorder (PMDD), or postpartum depression, which suggests some women have a particular sensitivity to hormonal shifts across their lives.
This matters because perimenopausal depression is sometimes dismissed as "just hormones" or simply a stressful stage of life. Midlife often does bring real pressures, such as demanding careers, childcare, and aging parents. But when low mood, anxiety, or irritability persist for weeks and affect your work, relationships, or sense of self, they deserve a thoughtful evaluation and real treatment.
How it's evaluated:
There isn't a single blood test that diagnoses perimenopause, because hormone levels fluctuate so much. Diagnosis is based mostly on age, symptoms, and changes in your cycle. A careful evaluation also considers other contributors that can look similar, including thyroid conditions, anemia, sleep disorders, medication effects, and alcohol use. It also helps to track your symptoms alongside your cycle for a few months.
Treatment:
The good news is that perimenopausal mood symptoms respond well to treatment. The best plan depends on your symptoms, history, and preferences, and often combines approaches.
Antidepressants. SSRIs and SNRIs are first-line treatments for perimenopausal depression and anxiety. Some of these medications also reduce hot flashes, which can make them especially helpful when mood and vasomotor symptoms overlap.
Hormone therapy. For women with significant hot flashes and night sweats, hormone therapy can be very effective, and some research suggests estrogen may also improve mood during perimenopause specifically. Hormone therapy is prescribed by a gynecologist or primary care physician.
Psychotherapy. Cognitive behavioral therapy can ease depression and anxiety. Therapy is also a place to work through the identity and role shifts that often coincide with midlife.
Sleep. Because poor sleep amplifies nearly every symptom, treating it directly matters. Cognitive behavioral therapy for insomnia (CBT-I) is highly effective, and addressing night sweats can help sleep recover.
Foundations. Regular movement, reducing alcohol, and protecting time for rest and connection all support mood regulation during this transition.
You don't have to just push through.
Perimenopause is a normal life stage, but suffering through it isn't a requirement. If you've been feeling unlike yourself, your symptoms are worth taking seriously. Understanding what's happening in your brain and body is often the first step toward feeling steady again.
I offer psychiatric care and psychotherapy via telehealth for adults in Illinois, Wisconsin, Indiana, and Florida, and I work collaboratively with my patients' gynecologists and primary care physicians. If you'd like to talk about what you've been experiencing, schedule a free 15-minute consultation.