Common causes of female hair loss

Losing some hair each day is normal. Concern is more likely when shedding clearly increases, density reduces or the scalp becomes more visible. Common possibilities include:

• Female pattern hair loss.This usually causes gradual thinning over the crown and top of the scalp, often with a wider central parting.
• Telogen effluvium.Increased shedding may begin a few months after illness, high fever, surgery, major stress, childbirth, rapid weight loss or a significant dietary change.
• Hormonal transitions.Pregnancy, the postnatal period, perimenopause and menopause can alter the hair-growth cycle or reveal an underlying pattern of thinning.
• Iron, thyroid or nutritional problems.Low iron, thyroid disorders, inadequate protein or marked calorie restriction may contribute in some women.
• Hair styling and breakage.Tight hairstyles, extensions, chemical processing and frequent high heat can damage the hair shaft or place repeated tension on follicles.
• Inflammatory or autoimmune conditions.Alopecia areata can cause smooth patches, while scarring alopecias may involve redness, scale, discomfort or permanent follicle damage.

Why can hair start thinning in your 30s?

Hair thinning can begin at any adult age. In your 30s, common explanations include early female pattern hair loss, post-pregnancy shedding, stress, illness, iron deficiency, thyroid problems, restrictive dieting, medication changes or repeated tension from hairstyles.

The appearance offers clues. Hair coming out from across the whole scalp may suggest diffuse shedding, while a gradually widening parting or reduced density over the crown can fit female pattern hair loss. Short broken hairs may point towards damage rather than shedding from the root.

What may help your assessment

• Look back two to four months for illness, childbirth, major stress, surgery, weight loss or a dietary change.
• Note menstrual changes, acne, increased facial hair, tiredness, feeling cold or other new symptoms.
• Review medicines and hormonal contraception with a clinician or pharmacist rather than stopping them yourself.
• Take monthly photographs in the same lighting and parting instead of checking the mirror repeatedly.

Why does hair shed after having a baby?

During pregnancy, hormonal changes keep more hairs in the growing phase, so hair may appear thicker. After birth, many of those hairs move into the resting and shedding phases together. Increased shedding often becomes noticeable around three months after delivery.

Postpartum shedding is usually temporary, but recovery is gradual because hair grows slowly. Gentle hair care, regular meals and time are more useful than aggressive treatments or large doses of supplements.

How can perimenopause and menopause affect hair?

Hair thinning or hair loss can occur during perimenopause and menopause. Changes in hormone balance may shorten the growth phase or make genetically influenced female pattern hair loss more noticeable.

Menopause may be part of the picture without being the only cause. Iron deficiency, thyroid disease, illness, medicines, stress and scalp conditions can occur at the same time and should not be overlooked.

Look at the pattern as well as your age

1. Parting: Is the central part becoming wider or the scalp more visible over the crown?
2. Hairline: Is the front hairline moving backwards, or are the eyebrows also becoming thinner?
3. Scalp: Is there itching, burning, tenderness, redness or scale?
4. Shedding: Did a sudden increase begin a few months after illness, stress, surgery or weight loss?

Do not assume that hormone replacement therapy is automatically the answer to hair loss. Menopause symptoms and hair changes should be reviewed together so treatment decisions address your overall health and individual risks.

Could a health condition or medicine be involved?

Hair loss can occasionally be a sign of an underlying condition, particularly when it is sudden, persistent or accompanied by other symptoms.

Conditions that may contribute

• Iron deficiency: may also cause tiredness, breathlessness, paler skin, headaches or restless legs.
• Thyroid disorders: may be accompanied by fatigue, temperature sensitivity, weight change, constipation, palpitations or menstrual changes.
• PCOS or androgen-related changes: may occur with irregular periods, acne, increased facial hair or fertility concerns.
• Alopecia areata or scarring alopecia: may cause smooth patches, hairline recession, eyebrow loss or scalp inflammation and needs a clear diagnosis.

Medicines that may affect weight

Some medicines and medical treatments can contribute to shedding or thinning. Do not stop prescribed medicine yourself. Ask a GP, pharmacist or prescriber whether hair loss is a recognised effect and whether your treatment needs review.

Does a widening parting mean female pattern hair loss?

A gradually widening central parting with reduced density over the top of the scalp is a common presentation of female pattern hair loss. The front hairline is often retained, although the scalp may become increasingly visible.

A widening parting is an important clue, but it is not a diagnosis by itself. Diffuse shedding, breakage and inflammatory scalp conditions can overlap, so the whole pattern should be assessed.

Compare photographs taken several months apart in similar lighting. Constant daily checking can make small variations in styling or light look more significant than they are.

A simple six-week hair review

Hair changes are slow, so a short period of consistent observation is usually more useful than changing products every few days.

1. Photograph the pattern. Use the same parting, lighting and angle every two to four weeks.
2. Review possible triggers. Note childbirth, illness, surgery, stress, dietary change, rapid weight loss and new medicines from the previous few months.
3. Protect the hair you have. Reduce tight styles, harsh chemicals and excessive heat, and handle wet hair gently.
4. Prepare for an assessment. Record menstrual changes, menopause symptoms, scalp discomfort, family history and any loss of brows or lashes.

When should you speak with a clinician?

Arrange medical advice if hair loss is sudden, patchy, rapidly worsening or persistent, or if the scalp is painful, red, scarred or very scaly. Also seek assessment if hair loss occurs with marked fatigue, heavy periods, irregular periods, acne, increased facial hair or unexplained weight change.

Prompt assessment is especially important when the frontal hairline or eyebrows are receding, because some inflammatory scarring conditions can cause permanent loss if follicles are damaged.