Does hair thinning get worse before your period during perimenopause?

Yes, many women notice that hair thinning intensifies in the days before their period arrives, and during perimenopause this pattern can become significantly more pronounced. This is not imagined. There are real hormonal mechanisms driving it, and they are amplified by the erratic cycle changes that define perimenopause.

In a normal cycle, estrogen and progesterone rise and fall in a relatively predictable pattern. But during perimenopause, ovulation becomes irregular, which means progesterone production in the second half of your cycle is often lower than it should be. At the same time, estrogen can spike higher than normal and then drop more sharply. This steep late-luteal drop in both hormones is what sets off many premenstrual symptoms, and hair is particularly sensitive to it.

Hair goes through growth phases: anagen (active growth), catagen (transition), and telogen (resting and shedding). Estrogen prolongs the anagen phase, keeping hair in active growth longer. When estrogen drops sharply in the premenstrual window, more follicles may be nudged prematurely into the resting phase. This process, called telogen effluvium, does not show up as shedding immediately but tends to manifest two to three months after the hormonal trigger. During perimenopause, with fluctuations happening cycle after cycle, this can create a chronic, low-level telogen effluvium that feels like it is always worst around your period because each cycle's drop adds to the cumulative effect.

The premenstrual rise in androgens also plays a role. In some women, the relative drop in progesterone combined with a small premenstrual androgen surge increases sensitivity at the hair follicle level, particularly in women who are genetically predisposed to androgenic hair thinning. Progesterone itself helps block DHT, the androgen most directly tied to follicle miniaturization, so when progesterone falls, this protective effect weakens.

Stress compounds this considerably. Cortisol spikes premenstrually in response to the hormonal turbulence, and chronically elevated cortisol shortens the anagen phase and constricts blood flow to follicles. If your sleep is also disrupted in the premenstrual window, which is common in perimenopause due to night sweats and anxiety, this adds another cortisol load on top of the hormonal one.

The most practical thing you can do is address the factors you can control. First, get your iron levels checked with a full panel including ferritin. Many perimenopausal women have ferritin levels below 50 ng/mL, which is technically within the normal reference range but is low enough to impair hair growth. Heavier periods, which become common in early perimenopause, accelerate iron loss. Correcting low ferritin can produce noticeable improvement in hair shedding over three to six months. Zinc and vitamin D deficiency also affect hair cycling and are worth checking. Second, be gentle with your hair in the premenstrual window: avoid heat styling, tight hairstyles, and harsh chemical treatments. Third, managing stress through regular movement, sleep protection, and stress-reduction techniques reduces the cortisol-driven component.

Nutrition plays a role that is worth taking seriously. Beyond iron and ferritin, adequate protein is essential for hair structure, since hair is made primarily of keratin. Women who eat insufficient protein, particularly those skipping meals or eating low-calorie diets, may exacerbate hormonally driven hair loss. Biotin deficiency is another factor, though true deficiency is rare and biotin supplements are unlikely to help unless you are genuinely deficient. Selenium and omega-3 fatty acids have some preliminary evidence for supporting scalp health and reducing inflammation around follicles. The strongest dietary intervention you can make is ensuring you meet protein targets, roughly 1.2 to 1.6 grams per kilogram of body weight daily, alongside a varied whole-foods diet that covers micronutrient bases.

Timeline expectations are important. Hair grows roughly 1 cm per month, and the telogen-to-anagen cycle takes several months to reset. Even with the right interventions, improvements in hair density take three to six months to become visible. Do not give up on a strategy after just a few weeks.

See a doctor if you are losing hair in patches rather than diffusely, if hair loss is accelerating significantly, if you have other symptoms of thyroid dysfunction (fatigue, weight changes, cold intolerance), or if you notice hair thinning at the frontal hairline in a pattern that suggests androgenic alopecia. These scenarios benefit from a dermatology referral and targeted treatment rather than general hormonal support alone. Talk to your healthcare provider about the right approach for your specific situation.

The PeriPlan app (https://apps.apple.com/app/periplan/id6740066498) lets you log hair thinning daily so you can spot whether patterns shift over time and identify where in your cycle symptoms peak.

This content is for informational purposes only and does not replace medical advice. Always consult your healthcare provider about your specific situation.