Why Understanding Your Menstrual Cycle is Important.

Your menstrual cycle is not just a monthly period — it’s a dynamic series of hormonal, ovarian, and uterine changes that affect your energy, mood, and overall wellbeing. Understanding your cycle helps you:

• Recognise natural patterns in energy, focus, and emotions.
• Identify signs of hormonal imbalance or irregular ovulation.
• Plan your lifestyle, diet, and activities in harmony with your hormones.
• Detect early warning signs for conditions such as PCOS, thyroid issues, or iron deficiency.

Common misconception: Many people think the follicular phase only starts after menstruation. In fact, menstruation is part of the follicular phase — it begins on day 1 of your cycle and continues until ovulation. technically, there are four phases: menstrual, follicular, ovulatory, and luteal — though the follicular phase includes menstruation, which is often overlooked.

What are the different phases of the menstrual cycle?

Your menstrual cycle is divided into four phases, each with unique hormonal, ovarian, and uterine changes that affect your mood, energy, and overall wellbeing:

1. Menstrual Phase (Early Follicular)
2. Late Follicular Phase (Pre-Ovulation)
3. Ovulation Phase
4. Luteal Phase (Secretory)

Understanding these phases helps you work with your body, track fertility, and notice irregularities that may signal hormonal imbalance.

How Long is a Normal Menstrual Cycle?

• Typical menstrual cycle length: 21–35 days (28 days is often cited, but only ~10% of women have a textbook 28-day cycle).
• Menstrual cycle length varies due to stress, illness, nutrient deficiencies, hormone imbalances, or lifestyle changes.
• Ovulation timing shifts depending on total cycle length:
• 28-day cycle → ovulation around day 14
• 35-day cycle → ovulation around day 21
• 21-day cycle → ovulation around day 7

Follicular Phase (Day 1 to Ovulation)

The follicular phase begins on day 1 of your cycle and continues until ovulation. It is divided into two sub-phases:

Menstrual Phase (Early Follicular Phase)

Length / Timing

• Typically Day 1–5 of the cycle (this varies for each person)
• The menstrual phase starts when the released egg is left unfertilised and the uterus sheds all but the deepest part of its endometrium.
• A healthy menstrual phase lasts between two to seven day, which may include a day or two of spotting before and after.

Hormonal Changes

• Oestrogen and progesterone are at their lowest, which signals the uterus to shed its lining.
• FSH (follicle-stimulating hormone) begins to rise slightly to prepare for the next cycle , which stimulates the growth of several follicles in the ovary.
• This low-hormone environment impacts the neurochemicals that influence energy and
  motivation levels, which can make some women feel more fatigued or emotionally sensitive.

Ovarian & Uterine Activity

• The uterine lining (endometrium) sheds. Menstruation starts when a released egg isn’t fertilised, and the uterus sheds most of its lining, keeping just the base layer to start the next cycle.
• Inside your ovaries, several tiny egg-containing sacs called follicles start to grow and develop, getting ready for one to be released at ovulation. (StatPearls, NCBI).
• Follicle recruitment is a competitive process — only one dominant follicle will continue to grow and eventually ovulate, while others shrink.

Signs & Symptoms

• Bleeding (from light to heavy, depending on the individual), cramps, and bloating are common (but not necessarily normal).
• Some women experience headaches, breast tenderness, diarrhoea or mild fluid retention.
• Cervical mucus may be scant and sticky at the beginning of this phase.
• Basal body temperature is usually lower during menstruation, which reflects the low progesterone levels at the start of the cycle.

How you may feel / emotions

• Your mood can be lower during bleeding days, with some experiencing irritability or heightened sensitivity.
• Energy tends to be lower, which can be worsened if periods are heavy and iron levels drop. Iron deficiency from blood loss can contribute to fatigue, low motivation, and difficulty concentrating.
• Mental focus may improve gradually as oestrogen begins to rise later in this phase.

Practical Tips / Self-Care

• Iron-Rich Foods: Incorporate iron-rich foods into your diet, such as slow-cooked red meats, green-lipped mussels, leafy greens, legumes such as lentils, beetroot. Pair these with vitamin C-rich foods to enhance iron absorption.
• Monitor Iron Levels: If you experience fatigue, have a heavy period, are vegan or vegetarian, consult with your GP to check your iron levels.
• Balanced Diet: Ensure a balanced diet that supports overall health, including adequate protein, healthy fats, and complex carbohydrates, to maintain energy levels throughout the menstrual cycle.
• For more detailed information on the importance of iron in women’s health and how to maintain optimal levels, you can refer to our comprehensive guide: Why Iron is Important for Women’s Health
• Allow yourself to go slow and rest. This is the time to reflect, rest and restore. The more you rest, restore and nourish yourself during this phase the more you will have in reserve for the rest of your cycle

Late Follicular Phase (Pre-Ovulation)

Length / Timing

This phase can vary in length (normally from 4 – 7 days but can last over 10 days) and is often where cycle irregularities show up — particularly when your body is under stress. During this time, the dominant follicle matures and prepares for ovulation, while stress or illness can delay this process. If your cycles fluctuate, this is often where the variation occurs. Studies support this and show that chronic psychological stress may interfere with the LH surge of the late follicular phase and delay ovulation (Vigil et al., 2022).

For more on how stress affects your menstrual cycle, see my post: How Does Stress Affect Your Period?

Hormonal Changes

• Oestrogen continues to rise sharply, thickens the uterine lining and boosts cervical mucus production.
• FSH (follicle-stimulating hormone) stimulates the growth of several follicles, but usually only one becomes dominant and continues to mature.
• LH (luteinising hormone) levels begin to rise, preparing for the LH surge that triggers ovulation. This LH surge is essential — it signals the ovary to release the mature egg, marking the transition into the ovulatory phase.

Clinician Insight:
The medication letrozole can temporarily lower oestrogen, encouraging FSH release, stronger LH surge, and improved ovulation chances.

Practical Tip:
Ovulation predictor kits detect the LH surge, which helps women identify their most fertile days. Tracking this can be especially useful if you are trying to conceive.

Ovarian & Uterine Activity

• Follicle development: By this stage of the menstrual cycle, one dominant follicle continues to mature while the others stop developing.
  • Occasionally, two dominant follicles may fully mature during this phase. If both are released during ovulation and fertilised, this is how fraternal twins can occur.
• Uterine lining changes: The uterine lining continues to rebuild, thicken and becomes more nutrient dense, under the influence of oestrogen, in preparation for possible implantation .
• Hormonal communication: The hypothalamus and pituitary gland play key roles here — the pituitary releases FSH, and later luteinising hormone (LH), which prepares the dominant follicle for ovulation.

Signs and Symptoms:

• Cervical mucus: As oestrogen rises, cervical mucus becomes clear, slippery, and stretchy — often compared to raw egg white — which signals your most fertile days (Bigelow et al., 2004
• Slight increase in libido or mood lift may occur as oestrogen levels peak.
• Basal body temperature remains low until ovulation.
• Some women notice breast tenderness or mild bloating.

How You May Feel / Emotions

• Many women notice increased energy, motivation, and mood improvement in the days leading up to ovulation.
• Some women feel more confident, sociable, or motivated — likely influenced by the rise in oestrogen and the increase of neurochemical levels.
• Mild tension or irritability can appear if stress is high.

Practical Tips / Self-Care

• Track fertility signs: cervical mucus, BBT, and cycle apps to anticipate ovulation.
• Support nutrition: ensure adequate protein, iron, and micronutrients to maintain energy during heavy menstrual cycles.
• Manage stress: yoga, meditation, or gentle exercise can help support healthy hormonal balance.
• Sleep well: adequate rest supports oestrogen regulation and follicle development.
• Hydrate & move: light exercise and water intake supports circulation and reduces bloating.

Ovulation Phase

Length / Timing

• In a textbook 28-day cycle, ovulation typically occurs around day 14. However, since ovulation usually happens about 14 days before the start of the next period, it shifts with cycle length — for example, in a 35-day cycle ovulation may occur around day 21, while in a 21-day cycle it may occur around day 7.
• Egg is fertile for ~4–5 days; ovulation occurs 10–12 hours after LH peak. (NCBI).

Hormonal Activity

• Oestrogen peaks just before ovulation, stimulating a surge in LH.
• The LH surge triggers the final maturation of the dominant follicle and the release of the egg (ovum) from the ovary (NCBI).
• Follicle-stimulating hormone (FSH) also rises briefly to support follicle maturation (NCBI).

Ovarian & Uterine Activity

• The dominant follicle ruptures, releasing the mature egg into the abdominal cavity.
• The egg is captured by the fimbriae of the fallopian tube, where it may be fertilized if sperm is present.
• The ruptured follicle transforms into the corpus luteum, which secretes progesterone to prepare the uterine lining for potential implantation (NCBI).

Signs & Symptoms

• Cervical mucus becomes clear, slippery, and stretchy, resembling “egg white” consistency, indicating peak fertility.
• A slight increase in libido may occur due to hormonal changes.
• Some women experience Mittelschmerz, a mild, one-sided lower abdominal pain occurring around ovulation. NCBI

How You May Feel / Emotions

• Around ovulation, energy, libido, and mental clarity often peak — this is typically when you may feel your best during the cycle (Fink et al, 1996 and Giltray eta l, 2008).
• Increased self-confidence and a natural sense of generosity and nurturing.
• A great time to communicate, socialise, and connect with friends, community, or colleagues.
• This is the ideal menstrual phase to try new activities, turn ideas into action, and schedule important meetings or conversations.

Practical Tips / Self-Care

• Track ovulation through basal body temperature charting and monitoring cervical mucus changes, or use LH surge detection kits.
  • Learn the essentials to chart your menstrual cycle – the right way – with my Menstrual Cycle And Symptoms Charts
• Maintain a balanced diet rich in nutrients to support hormonal balance.
• Engage in regular physical activity to promote overall health and well-being.
• Manage stress through relaxation techniques such as meditation or yoga to support hormonal health.

Luteal Phase (Secretory Phase)

Length / Timing

• Typically days 15–28 of a textbook 28-day cycle (healthy range: 12–16 days).
• The luteal phase is the most consistent and stable phase of the menstrual cycle. Unlike the follicular phase, which can vary depending on stress, illness, or lifestyle, the luteal phase length is largely determined by corpus luteum function.
• In ovulatory cycles, the corpus luteum produces progesterone, which supports a stable length and predictable hormonal pattern.
• Reference:
• Worsley R et al., 2020. Progesterone and menstrual cycle regulation. Front Endocrinol 11:590

Hormonal Activity

• In a normal luteal phase after ovulation, the corpus luteum produces progesterone, which peaks about mid-luteal phase. This balances oestrogen and supports the endometrium for possible implantation.
• If pregnancy does not occur, the corpus luteum degenerates, which leads to a decline in progesterone and oestrogen levels, triggering menstruation.
• In an anovulatory cycle (when ovulation doesn’t occur), no corpus luteum forms, so progesterone is not produced adequately.
• Without this progesterone peak, oestrogen becomes relatively dominant, which can contribute to PMS-like symptoms, bloating, breast tenderness, irritability, and other luteal-phase issues.
• Key point: Relative oestrogen dominance is not about high absolute oestrogen, but rather a low progesterone to oestrogen ratio, which is typical in anovulatory cycles.
• References:
• Worsley R et al., 2020. Progesterone and menstrual cycle regulation. Front Endocrinol 11:590.

Ovarian & Uterine Activity

• The endometrium thickens and matures under the influence of progesterone, preparing for potential embryo implantation.
• If no fertilisation occurs, the endometrium sheds, which marks the start of the menstrual (next) cycle.
• This phase is typically stable in length, dictated by the corpus luteum function.
• In anovulatory cycles, low progesterone relative to oestrogen can result in irregular shedding or luteal phase abnormalities.

Signs & Symptoms

• Cervical mucus becomes thicker and less abundant.
• Basal body temperature is elevated if you ovulate due to progesterone.
  • Note: If ovulation does not occur, BBT may not show the typical post-ovulatory rise, which can indicate an anovulatory cycle.
• Typical PMS symptoms may appear, including:
  • Mood swings, irritability, or anxiety
  • Fatigue and low energy
  • Food cravings or changes in appetite
  • Headaches or mild aches and pains
  • Breast tenderness, bloating, and fluid retention
• These symptoms typically arise during the luteal phase and subside with the onset of menstruation (Gudipally and Sharma, 2024 ).

How You May Feel / Emotions

• Calmer and more introspective: A strong progesterone surge promotes ‘relaxing’ neurochemicals, which supports restful sleep and a sense of calm.
• Lower physical energy: As progesterone and oestrogen drop towards the end of the luteal phase, you may feel more tired and less motivated for high-energy activities.
• Emotional changes: Reduced oestrogen can lead to less empathy or increased sensitivity.
• Need for self-care: This is a natural time to nest, declutter, cook in bulk, and protect your boundaries.
• PMS awareness: You may notice bloating, breast tenderness, mood changes, headaches, or irritability, especially if ovulation did not occur.
• (Barberi, 2014)

Practical Tips / Self-Care

• Engage in gentle exercise like walking or yoga to alleviate bloating and improve mood.
• Prioritise sleep hygiene to enhance restfulness.
• Practice mindfulness or journaling to process emotions and maintain mental well-being.
• Nourish your body with balanced meals rich in complex carbohydrates, wholesome proteins, and healthy fats to support hormonal balance.

Quick Reference: Energy & Hormones by Menstrual Phase

Where to from here?

Your menstrual cycle offers valuable insights into your health and fertility. Tracking and understanding it can:

• Reveal patterns and potential hormonal imbalances.
• Help plan lifestyle and self-care in alignment with hormones.
• Signal when to consult a healthcare provider for PCOS, thyroid, iron deficiency, or irregular cycles.

Remember: No two cycles are identical, and symptoms may vary cycle-to-cycle. Tracking your cycle helps you notice unique patterns and influences.

Seek advice from a naturopath or qualified healthcare practitioner for personalised guidance on herbs, nutrition, and lifestyle strategies that support hormonal health.

Kia ora, I’m Anna Jolly

I’m a degree-qualified naturopath and medical herbalist based in Aotearoa / New Zealand with a focus on women’s hormones, fertility and menstrual health.

Through Anna Naturally, I combine evidence-informed practice with traditional herbal medicine and a root-cause approach to help women better understand their bodies and create sustainable changes that fit real life.

Meet Anna and learn more about my approach.
Media & collaborations →

Menstrual Cycle FAQs