How Spring Weather Affects Female Hormones

What happens to hormones in spring?
As the days get longer in spring, your body responds to the increased sunlight by changing hormone levels. Research shows that women tend to have higher levels of estrogen (the main female hormone) during spring months compared to other seasons. Your body also produces more follicle-stimulating hormone (FSH), which helps your ovaries prepare eggs for release.
Why does this happen?
The key factor is daylight. Longer spring days affect a small gland in your brain called the pineal gland, which produces a hormone called melatonin. You make less melatonin when days are longer and brighter. Since melatonin influences your reproductive hormones, less melatonin in spring means your ovaries become more active.
Think of it like this: your body has an internal calendar that uses sunlight to track the seasons. When spring arrives and days get longer, your brain receives this signal and adjusts your hormone production accordingly.
What effects might you notice?
- Studies using data from millions of women have found that longer days are associated with:
- Higher rates of ovulation (egg release)
- Increased sexual desire and activity
- Slightly elevated testosterone levels (which is normal and healthy in women)
These changes are generally subtle—most women won’t notice dramatic differences in how they feel day-to-day. The hormonal shifts happen naturally as part of your body’s seasonal rhythm.
Does this affect fertility?
The spring increase in reproductive hormones may have a small effect on fertility, though the research shows mixed results. Some studies suggest conception rates vary slightly by season, but many other factors (like your overall health, age, and timing of intercourse) are much more important than the time of year.
Is this normal?
Yes, completely normal. Humans, like many animals, have subtle seasonal patterns in their reproductive hormones. Even though we live in climate-controlled environments and aren’t as affected by seasons as our ancestors were, our bodies still respond to changing daylight throughout the year.


