The Role of Hormones in Your Menstrual Cycle

What Are Hormones & Why Are They Important in the Menstrual Cycle?
In the menstrual cycle, these hormones work together in a delicate balance to:
- Regulate your monthly period
- Prepare your body for pregnancy
- Control when you ovulate (release an egg)
The Four Phases of the Menstrual Cycle & Their Hormonal Changes
1. Menstrual Phase (Days 1–5)
This is when your period starts.
- At the end of your previous cycle, if pregnancy hasn’t happened, your estrogen and progesterone levels drop.
- This drop tells your body that it’s time to shed the uterine lining, which comes out as menstrual bleeding.
- This is your body's way of starting fresh and preparing for a new cycle.
After your period ends, your body starts preparing for ovulation.
- The brain sends a hormone called FSH (Follicle-Stimulating Hormone) to your ovaries.
- FSH tells your ovaries to start growing small sacs called follicles, each containing an immature egg.
- One of these follicles will become dominant and mature into an egg ready for release.
- Meanwhile, estrogen levels rise, which helps thicken the uterine lining so it’s ready to support a possible pregnancy.
This is the phase where the mature egg is released.
- A sudden spike in LH (Luteinizing Hormone)—called the LH surge—tells the dominant follicle it’s time to release the egg.
- This process is called ovulation, and it’s the most fertile time in your cycle.
- The egg travels into the fallopian tube, waiting to be fertilized by sperm.
After ovulation, your body prepares for pregnancy.
- The empty follicle that released the egg turns into something called the corpus luteum, which now produces progesterone.
- Progesterone helps maintain and further thicken the uterine lining, making it ready for a fertilized egg to implant.
- If pregnancy occurs, progesterone remains high to support the early stages.
- If pregnancy doesn’t happen, both estrogen and progesterone levels drop, and this hormonal drop triggers your next period.
Key Hormones & Their Role in Your Menstrual Cycle
Let’s understand what they do and why they matter.
1. Estrogen – The Growth Hormone
Estrogen is one of the most important female hormones. It is mainly produced by the ovaries and plays a major role in the first half of your menstrual cycle.
When it rises: Estrogen levels start to rise in the follicular phase (Day 6–14), helping the uterine lining grow and thicken in preparation for a possible pregnancy.
What it does:
- Helps build the uterine lining (endometrium)
- Improves mood, skin glow, and energy levels
- Supports bone health and brain function
If estrogen is too high: It may cause heavy bleeding, bloating, breast tenderness, and PMS symptoms like mood swings.
Maintaining a healthy level of estrogen is key for both menstrual and overall well-being.
2. Progesterone – The Pregnancy Hormone
Progesterone is another vital female hormone produced mainly after ovulation by a structure called the corpus luteum (the shell left behind after the egg is released).
When it rises: During the luteal phase (Day 15–28), progesterone increases to prepare the uterus for pregnancy.
What it does:
- Supports the implantation of a fertilized egg
- Stabilizes the uterine lining so it doesn’t shed too early
- Helps with better sleep, a calm mood, and metabolism
Without enough progesterone, even if you ovulate, pregnancy may not occur or be sustained.
3. FSH (Follicle-Stimulating Hormone) – The Egg Developer
FSH is produced by the pituitary gland in the brain. It helps your ovaries grow and mature the follicles (small sacs that contain eggs).
When it rises: FSH levels increase in the early follicular phase (Day 1–5).
What it does:
- Stimulates the growth of ovarian follicles
- Supports the development of a healthy egg for ovulation
Why it matters: Without enough FSH, eggs may not mature properly, making it harder to conceive.
4. LH (Luteinizing Hormone) – The Ovulation Trigger
LH is also released by the brain and works closely with FSH. It plays a key role in triggering ovulation.
When it peaks: LH has a sharp surge around Day 14, which leads to the release of the mature egg from the ovary – this is ovulation.
What it does:
- Triggers ovulation (egg release)
- Helps form the corpus luteum, which produces progesterone
If LH is too high (as in PCOS): It may lead to hormone imbalance and prevent normal ovulation.
Hormonal Imbalances & How to Fix Them
Common Hormonal Imbalances & Their Symptoms
- Missed or very light periods
- Vaginal dryness or discomfort during intercourse
- Low libido
- Hot flashes or night sweats (in severe cases)
- Heavy or painful periods
- Bloating and water retention
- Mood swings or irritability
- Breast tenderness
- Increased PMS symptoms
- Anxiety or sleep disturbances
- Irregular cycles or spotting before your period
- Difficulty conceiving
- PMS symptoms like mood swings, irritability, or breast tenderness
- Irregular or absent periods
- Acne and unwanted facial/body hair
- Weight gain, especially around the abdomen
- Difficulty getting pregnant
- Multiple small cysts in the ovaries (seen on ultrasound)
Natural Ways to Balance Hormones
1. Eat a Hormone-Friendly Diet
- Include healthy fats (avocados, coconut oil, nuts, seeds) to support estrogen production.
- Eat leafy greens and cruciferous vegetables (broccoli, cauliflower) to clear out excess hormones.
- Limit sugar and processed foods to prevent insulin resistance and hormonal issues.
- Do strength training to improve insulin sensitivity – especially helpful for PCOS.
- Try yoga, meditation, or walking to reduce cortisol (stress hormone).
- Aim for at least 30 minutes of movement daily.
- Sleep is vital for hormone repair and balance.
- Poor sleep disrupts melatonin and cortisol, affecting ovulation and cycle regularity.
- Get 7–8 hours of quality sleep nightly. Create a calming bedtime routine and avoid screens before sleep.
When to See a Doctor for Hormonal Issues
- Irregular, very heavy, or painful periods
- No periods for months at a time
- Unexplained infertility or difficulty conceiving
- Severe mood swings or PMS that interfere with your daily life
- Signs of PCOS or early menopause
By understanding your body, tracking your cycle, and making simple lifestyle changes, you can take control of your hormonal health. And if things still feel out of balance, don’t hesitate to seek help—support is always available.
Isha Women’s Hospital, under the expert guidance of Dr. Chinmay Pataki, specializes in diagnosing and treating hormonal imbalances, PCOS, irregular periods, and fertility concerns. Our compassionate team is here to guide you with personalized care, helping you restore balance and achieve your reproductive goals.
Frequently Asked Questions (FAQs)
Ans - A drop-in estrogen and progesterone cause the uterine lining to shed.
2. What hormone imbalance causes irregular periods?
Ans - Low progesterone or high estrogen can cause irregular periods.
3. How do I know if I have a hormonal imbalance?
Ans - Symptoms like acne, mood swings, weight gain, or irregular periods may indicate an imbalance.
4. Can diet help balance hormones?
Ans - Yes! Healthy fats, fiber, and avoiding sugar support hormone health.
5. When should I see a doctor for hormone issues?
Ans - If you have severe PMS, infertility, or unpredictable cycles, consult a doctor.