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When a girl attains puberty, her body starts preparing for pregnancy, every month. This increases the level of hormones like Estrogen, Progesterone, FSH and LH. The uterus lining starts thickening by depositing blood to support pregnancy. The ovaries start releasing eggs every month. However, if there is no sperm in the fallopian tube to fertilise the egg, the body starts preparing to shed the uterus lining along with the egg. This phase of bleeding to remove the uterus lining, every month, is called menstruation. The entire monthly cycle is known as menstruation cycle.​ The bleeding continues for 3 to 8 days and this cycle repeats at regular intervals of 21 to 35 days in every woman, if pregnancy is not achieved. The menstrual flow generally repeats after a fixed interval in each menstruation cycle. 

The structure of the Female reproductive system

Phases of Menstrual Cycle

Here the average menstruation cycle is considered to be 28 days. It may vary from 21 to 35 days in most women.

Phases of the menstrual cycle, day by day

Driven by hormones, major changes occur in the ovaries and the endometrial part of the uterus, during the menstruation cycle. Therefore, the process of menstruation can be divided into:

  • The Ovarian Cycle

  • The Endometrial Cycle

Hormone levels over the menstrual cycle

1. The Ovarian Cycle

Ovary is the primary female reproductive organ. It contains the female gametes, known as the ovum or the egg. The ovum goes through several changes during the lifetime of a woman, to become a mature gamete. Let us understand these phases of ovarian cycle in details:

  • Antral Phase

  • Ovulatory Phase

  • Luteal Phase 

Antral Phase of the Ovarian Cycle

  • When a female child is born, there are millions of immature ova present in the ovary. These eggs are surrounded by nutrition providing cells, known as the primordial follicles

  • Until puberty, the Ovarian Maturation Inhibition Factor (OMIF) prevents the maturation of the primary follicles present in the ovum

  • The primordial follicles slowly develop to form primary follicles, which is also accompanied by the enlargement of the ovum

  • Once a girl attains puberty, the levels of FSH and LH hormones rise in her body  

  • FSH is produced in higher quantities as compared to LH. This causes the Follicular cells around the ovum to multiply at a faster rate and leads to the formation of protective layers around the ovum

  • These follicular cells produce a glass like fluid (knowns as antrum) which accumulates inside a cavity around the ovum. The secretions of the antrum also contain estrogen

Thus far, the stage of the ovarian cycle, is known as the Antral Phase


Ovulatory phase of the Ovarian Cycle

In a 28-day cycle, the ovum is released from the thick structure surrounding it, on the 14th day of the menstrual cycle. The process of the release of the ovum is known as ovulation.

  • The LH levels start rising around 16 hours prior to ovulation, rising as high as 6 to 10 times the normal level

  • The levels of estrogen begin to fall, simultaneously, and the follicular cells now start producing progesterone

  • All of these events trigger the process of ovulation

After the ovum is released into the ovary, the remnants of the surrounding cells start to degenerate. This makes up the next phase of the ovarian cycle, known as the luteal phase.

Luteal phase of the Ovarian Cycle

The luteal phase begins after the first few hours of ovulation. After releasing the egg, the follicles rupture. 

  • The ruptured follicle starts accumulating fat droplets, which makes it yellow in color. This fat filled follicle is now known as the Corpus Luteum 

  • Corpus Luteum secretes large amounts of estrogen and progesterone

  • If there is no fertilisation of the ovum by the sperm, the corpus luteum undergoes degeneration. This decreases the levels of estrogen and progesterone

Note that during pregnancy, Placenta secretes Human Chorionic Gonadotropin (HCG) hormone which acts on the corpus luteum to prolong it’s life and thus maintaining the pregnancy. 


2. The Endometrial Cycle

As the ovum goes through the ovarian cycle, simultaneous changes occur in the endometrial lining of the uterus. The endometrial cycle can be divided into 2 phases: 

  • The proliferative phase 

  • The secretory phase

Endometrial thickness during the menstrual cycle

The Proliferative Phase of the Endometrial Cycle

The proliferative phase is characterised by the rapid increase in the number of cells lining the endometrium.

  • This process starts on day 4-7 of the menstruation cycle

  • This is also known as the estrogen phase as the increased release of estrogen from cells in the ovary result in the growth of the uterine lining 

The proliferative phase ends once the process of ovulation occurs in the ovary and the next phase begins, known as the secretory phase.

The Secretory Phase of the Endometrial Cycle

The secretory phase is also known as the progesterone phase. It starts right after the ovum is released, i.e , after the process of ovulation. 

  • The glands present in the endometrium start growing in size and number, thickening the lining

  • The proliferation provides a nutritious environment for implantation of the fertilised ovum 

  • However, if fertilisation of the ovum does not occur and there is no pregnancy by the last two days of the monthly 28 day cycle, menstruation occurs

  • Menstruation is primarily stimulated by the decreased levels of estrogen and progesterone by the end of the monthly cycle

  • The endometrium lining reduces in thickness by 65% during menstruation. All the secretory glands begin to degenerate. The blood vessels also start to constrict and the degenerated parts start to separate from the uterine lining

  • The process of blood discharge begins 2 days after the onset of menstruation. The blood sheds in the form of fluids or clots from the vagina

Note that menstruation occurs in a monthly fashion and continues from the onset of puberty until menopause is achieved in the late 50s. During menopause, a woman goes through several hormonal changes, which ceases the process of monthly menstruation. After menopause, a woman is no longer capable of achieving pregnancy.



Dealing with the signs and symptoms of menstruation

Symptoms and Signs

There are some common symptoms which start a few days before menstruation. This phase is also called PMS (premenstrual syndrome).

  • Bleeding once every 21-35 days, lasting for about 3-8 days

  • Headache 

  • Acne

  • Bloating

  • Abdominal pain 

  • Pelvic cramps

  • Lower back pain

  • Tiredness

  • Mood swings

  • Soreness in breast 

  • Craving of certain food

  • Diarrhoea 

  • Nausea

  • Fatigue

Dealing with pain during Menstruation

Handling pain during menstruation

Period cramps and pain can be really annoying. It can break the regular ease of life and make you irritated. Here are few tips on how to soothe the pain:

  • Certain medications can ease the pain during menstruation:

  1. Birth control pills

  2. Non inflammatory steroid drugs (NSAIDs) - commonly sold under the label of Ibuprofen, Meftal-Spas, Aspirin, etc.

Please remember to consult a gynaecologist before taking any medicine, to avoid any allergies and side effects. Most of these medicines are available over the counter (OTC) in pharmacies. 

  • Use a heating pad to ease the cramps and pain in abdomen and back

  • Massage with essential oils

  • Drink green tea or chamomile tea

  • Have dark chocolate

  • Avoid coffee, tea and cold drinks

  • Continue with simple workout and regular exercises/yoga. This improves blood flow in the pelvic region

  • Sleep at least 8 hours to get enough rest

  • Having sex also reduces the pain

Menstrual Products

There are a variety of menstrual hygiene products available in the market.

Menstrual cloth
Disposable pad
Menstrual cup
Reusable pad
period underwear
Menstrual products and their cost, wear time, health risk and replacement time
How to use a disposable sanitary napkin or pad
How to use a reusable sanitary napkin or pad
How to use a tampon
How to use a menstrual cup
How to use a period underwear

Menstrual Hygiene

Maintaining proper hygiene is very critical during periods. This helps in reducing bacterial growth, rashes, skin irritation, unpleasant odour and the chances of TSS (toxic shock syndrome). Here are some safe practices to follow:

  • Change sanitary napkins/tampons/cups every 6 hours. If the flow is heavy, change them every 4 hours 

  • Use unscented products as the scent/smell can irritate the vagina and cause swelling in the pelvic region

  • Proper disposal of pads/tampons is very critical as it may attract infection causing microbes otherwise. Always wrap them in paper and dispose in a bin

  • Wash menstrual cups with mild soap and warm water after each use. Dry it completely before storing it

  • If you are using reusable pads, clean them thoroughly and always sun dry them

  • Always wash your hands properly before changing the pad/tampon/cup

  • Always wash/wipe the pelvic region before wearing a new pad/tampon/menstrual cup to remove the external blood. Wipe the genitals from front to back to avoid any bacteria from anus coming in contact with the vagina

  • Take lukewarm baths during periods

  • Always dry your underwear in the sun to remove any bacteria

  • Never douche the vagina during periods

  • Do not wear two napkins or a napkin and a cup or a napkin and a tampon together as this may increase the chances of bacterial infection and cause uneasiness

What is Toxic Shock Syndrome? 

Toxic shock syndrome is a life-threatening condition. Staphylococcus aureus is the bacteria responsible for TSS. TSS develops when the bacteria enters the blood stream and starts producing toxins. TSS can affect men, children and women through open skin wounds and surgeries, etc. Women are at an enhanced risk due to the usage of sanitary napkins, tampons, menstrual cups, contraceptive sponges, diaphragms etc. 
Changing blood-soaked pads/tampons/caps during menstruation is very important. 
Keeping them on for prolonged time can cause bacterial growth, increasing the risk of Toxic Shock Syndrome (TSS).


Symptoms of TSS

  • Sudden fever during periods while using pads/tampons/caps

  • Excessive bleeding

  • Severe abdominal and pelvic pain

  • Menstrual irregularities in bleeding

  • Low blood pressure

  • Head and muscle aches

  • Nausea and vomiting

  • Rashes in palms and toes

  • Redness of eyes, mouth and throat

  • Seizures

  • Confused thought process

If TSS is not treated timely, it may impact other body organs as well, leading to:

  • Liver failure

  • Kidney failure

  • Heart failure

  • Reduced blood flow in the body


The woman should consider visiting a doctor immediately if these symptoms are observed after prolonged use of pads/tampons/cups.


Menstrual Complications that require Medical Attention

  • Menstruation has not begun until the age of 15

  • Sudden pause in menstruation cycle for 3 months or more

  • Irregular menstrual cycles

  • Bleeding during menstruation lasts for more than a week

  • Two episodes of menstruation within a month

  • Extremely heavy bleeding and the need to change pad/tampon every 2-3 hours 

  • Sudden bleeding between two monthly cycles

  • Severe pain during periods with or without vomiting, nausea etc

  • Fever after using tampons for a prolonged period 

Facts about Menstrual cycle:

  • A girl becomes capable of pregnancy after menarche

  • A girl can get pregnant during her periods as well

  • Period blood is not dirty or impure

  • Periods do not make you physically impure

  • Average bleeding occurs for 3-8 days. The heaviest flow is on day 2

  • The blood lost in each cycle is about 60-80 ml, but it seems much more because of other components like vaginal fluids, cervical mucus, endometrial cells, etc.

  • Periods stop in early 50s for most women, this is called Menopause

  • A woman is most fertile around day 14 of her cycle (in a monthly cycle of 28 days), due to ovulation

  • The chances of pregnancy apart from ovulation week is very low 

  • Missed periods do not always indicate pregnancy

  • A woman gets approximately 480 periods, lasting 5 days on average, during her lifetime, which is ~2400 days. This is approximately 6 years of her life

  • Your body might smell during periods

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