Understanding Menstruation in Remote Environments

21st March 2025

Let’s talk about Periods.

Menstruation is not a ‘Medical Condition’ in the sense that the other topics featured in these articles are, but the process is certainly medical and it is a condition which will affect almost half of the population for almost half of their lives.

But we never talk about it.  Menstruation and periods are a Taboo topic (1, 2)

Where the practical implications of menstruation have been studied, it tends to be on the biological changes affecting athletic performance in a sports context (3-6) although there is ample qualitative research revealing women’s feelings of missing out on practical activities or social exclusion, especially in a remote travel or wilderness context. (6-12)  

Sadly, many of the reasons behind these barriers – whether imposed or self-imposed - are usually to do with attitudes and a lack of practical solutions for dealing with periods in remote or wilderness settings.

 

Menstruation

Menstruation is the shedding of the uterus lining whilst Prementrual Syndrome (PMS) refers to symptoms experienced leading up to menstruation. (13)

The period starts on Day One with the first bleed and usually lasts between 3 to seven days.  This is the Period or Mense.

The menstrual cycle length can vary between 20 and 45 days in adolescents, decreasing to between 24 and 38 days with increasing maturity but typically between 28 and 32 days. (14)

Breakthrough bleeding refers to unexpected vaginal bleeding or spotting that occurs between regular menstrual periods, often seen in women using hormonal birth control methods like the pill or IUD.

Many women experience abnormal cycles such as

  • menorrhagia (excessive blood flow and/or lasting longer than seven days)

  • oligomenorrhea (infrequent periods)

  • complete amenorrhea (absence of menstruation)

  • anovulatory cycles (where ovulation does not occur).

Normal and abnormal cycles and flow can cause pain, discomfort, fatigue, bowel issues and mood swings although some women may have few if any of these symptoms. (8)

Menstruation causes

  1. A physical response

  2. An emotional response

  3. Practical implications of managing hygiene and waste

Managing the practical implications is relatively straightforward, requiring understanding, hygiene, time, privacy and usually expenditure to purchase sanitary products. 

 Both of the physical and emotional responses to the menstrual cycle are related to the fluctuations in different hormones through each phase. These can be more challenging to manage.

Hormones produced by the pituitary gland (Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH)) are responsible for regulating the menstrual cycle as well as hormones produced by the ovaries like oestrogen and progesterone.   The hypothalamus-pituitary-ovarian axis is responsible for mutual stimulation. (15)

In one study (8) the symptoms that women experience during PMS (multiple answers permitted) displayed a range of predictable responses with mood swings, cramps and tiredness being the most predominant.

Analysis of 100 repsondants to typical symptoms of PMS. Prince, 2022 (8)



The Menstrual Cycle

Early Follicular Phase: The Period.

The first 2 days are likely to be physically and emotionally challenging as the woman is transitioning out of her last cycle and may be experiencing the heaviest part of her periods; at this time she requires privacy and compassion as well as considering practical solutions for managing privacy, hygiene and waste disposal.

Some women may experience increased fatigue during the first days of the cycle, which affects sleep duration compared to the luteal phase. (16, 17)  In extreme cases, this has been a cause of short-term absenteeism in the workplace. (18)

 

Late Follicular Phase:  Building Eostrogen

As oestrogen builds so does confidence and extroverted tendencies meaning she may be more confident, engaged and present which will continue until ovulation around day 12-14.   

Studies have indicated a significant increase in positive states and emotions such as joy, increased concentration, and energy while also decreasing negative emotional states. (19)

Research indicates that oestrogen has a positive effect on mood and the reactivity of the brain’s reward centre appears to be highest during the follicular phase (20, 21)

There is then an increase in self-confidence, self-esteem, and attractiveness, which is also related to secreted oestrogen. (22)

Women may be more sociable and willing to make social connections, be more open to new acquaintances.  High oestrogen levels may increase feelings of attractiveness and self-confidence, which in turn promotes pro-social behaviour. (23)

Women in this phase are more likely to make risky decisions, which may indicate an increase in self-confidence and optimism. (24)

Paradoxically, meta-analyses also indicate higher cortisol levels in the follicular phase of the cycle than in the luteal phase. (25)

Now is the optimal time for managing conflict and challenges and engaging in socially interactive activities.

Vaginal discharge becomes creamy and whitish in the mid-to-late follicular phase, and just before and around ovulation, it becomes clear and stretchy, similar to wet egg white. (26-28)

 

Early Lutel Phase:  Ovulation

Following ovulation all hormones plummet dramatically; potentially leading to mood swings, irritability, anxiety, or even depression.  This hormonal rollercoaster also impacts other areas like sleep, energy levels, and sexual function.

Research has been conducted for many years on the concept of PMS, a menstrual syndrome that affects up to 40% of menstruating women.  The cause of the condition is not fully understood, but research suggests PMS occurs because of an abnormal neurotransmitter response with normal ovarian function.  Some of the most common symptoms reported by women are swelling, breast pain, migraine headaches, and mood swings.

The occurrence of the latter symptom in the second phase of the cycle is influenced by fluctuations in progesterone levels. (29)

Although the unpleasant symptoms disappear within the first few days after the start of a new cycle, for many, they are extremely unpleasant, negatively affecting quality of life. 

The most reported symptoms involving mood changes are constant feelings of anxiety, difficulty concentrating, excessive sensitivity, feelings of anger, and depressive states. (29)

Mood swings may be more extreme in those who already suffer from anxiety. (30, 31)

Studies have shown that of the negative mentions brought on by PMS, it is only Anger that significantly increases during the perimenopausal period. (32)

In addition to the symptoms, PMS positively correlates with the occurrence of depression, stress, sleep and appetite disorders. (33)

Nearly 9 out of 10 women reported somatic symptoms, which accounted for most of all symptoms recorded during the breakthrough of menstrual cycles. (34)

These include

  • Changing cervical mucus.

  • Breast tenderness.

  • Ovulation pain.

  • Cervix position.

  • Changes in complexion.

  • Increase temperature.

Late Luteal Phase:  Progesterone

After ovulation, the ruptured follicle forms a corpus luteum (a temporary endocrine gland) that produces high levels of progesterone.  Towards the end of the cycle the corpus luteum breaks down, progesterone production decreases and the next menstrual cycle begins as FSH levels start to rise again.

Progesterone can lead to a variety of physical and emotional effects, including fatigue, mood swings, breast tenderness, and in some cases, anxiety or depression, depending on individual sensitivity.

When progesterone levels rise, women may tend to be more introspective and less motivated to participate in social interactions, avoid confrontation and may be less assertive in interpersonal interactions. (30)

Similarly, women become more risk-averse (36) with higher levels of social anxiety. (36)

There is often a need to strengthen ties with loved ones (37).  The increase in progesterone, which is observed during this phase and exhibits a calming effect on the nervous system, may be the reason for increased feelings of fatigue and a decreased desire to engage in social life.

During this phase, women are less likely to take action to attract the attention of potential partners.  Women may be focused on stable, long-term relationships and show a greater desire for security and emotional support. (38)

 

Support

Despite all of this, it is clear that those who experience strong social support and practical assistance experience fewer symptoms, to a lesser degree and fewer variable mood changes. (23, 39, 40)

Women who are more knowledgeable about their bodies’ processes are often better able to cope with cycle symptoms and make more informed decisions about their health. (41, 42)

 

Complications with Remote Travel

The stresses of travelling, such as changes in diet, exercise, sleep patterns, and time zones can affect the hypothalamic-pituitary axis and cause irregularities in periods or potentially cause menstruation to stop entirely.  For long-term trips, keeping track of the last menstrual period may help track irregularities.

Physical Activity

Due to hormonal changes and their impact on mood, it is recommended to modify the frequency and intensity of training units throughout the cycle.  In a study by Hackney AC et al. (43), it was shown that during the follicular phase, women exhibit significantly higher and better recovery after a 90-minute running workout at an intensity of 70%.  Therefore, it can be concluded that a better choice would be to introduce strength or high-intensity training for the time after menstruation until ovulation.

Due to elevated basal temperatures, the mid-luteal phase has a potentially negative effect on prolonged exercise performance through elevated body temperature and potentially increased cardiovascular strain. Practical implications for women performing sustained physical activity may be the adjustment of work activities to suit their menstrual cycle, especially in hot, humid conditions. (44)

The same strategy, combined with light aerobic activity in the form of walking, can also be implemented during monthly bleeding. (43)

Before menstruation, too, due to the frequent occurrence of PMS, it is recommended that you reduce the intensity of your workout and choose activities that will help relax your muscles and thus reduce pain.

 

Altitude

Periods can be modified by high altitude in terms of duration, flow and regularity and are likely caused by changing environmental and diurnal factors including jet lag, exercise, cold, and weight loss. (45)

To avoid irregular periods, consider oral contraceptive medication or devices to regulate the menstrual cycle.  There is a theoretical risk that when using combined oral contraceptive pills, the risk of thrombosis is higher above 4,500.  This is because at higher altitudes, individuals also may experience polycythemia, dehydration, and cold exposure, but very few events have been reported. (46, 47)

With oral contraceptives there could be the possibility of decreased efficiency with some antibiotics, especially broad-spectrum penicillins and tetracyclines that are often taken prophylactically for vector-borne pathogens in some geographic regions. (46)

It is up to the healthcare provider and individual to determine the risk-benefit ratio of controlling menses while at high altitude and whether the use of hormonal contraceptives is how they wish to manage periods.

 

Abnormal uterine bleeding

Abnormal uterine bleeding is defined as a deviation from the normal menstrual bleeding pattern in menstruating women or any bleeding episode in postmenopausal women.  Obtaining an accurate history of the woman’s normal periods or previous cycles is most helpful followed by determining whether the bleeding is ovulatory or anovulatory.  The main goal when evaluating vaginal bleeding in the wilderness setting is to determine whether the bleeding is an emergency or something that can be managed in-country and addressed on their return home.

In an athletic population, special consideration should be made for the female athlete triad, which includes disordered eating, menstrual irregularities, and low bone density (45).  Any postmenopausal woman with abnormal uterine bleeding, although usually not emergent, should follow up with a primary care consultation to determine whether atrophy caused the bleeding or if a more serious underlying condition is the source (48).

 

Urinary tract concerns

Wilderness travel increases the risk of urinary tract infections secondary to dehydration, less frequent urination, and fewer facilities for hygiene.  Sexual intercourse also increases the risk of urinary tract infections. To decrease the risk of an infection, women should be urged to stay well hydrated and urinate when needed.

Practising outdoor peeing and wearing clothing conducive to outdoor peeing that allows for more convenient urination may help decrease infections.  There are also a number of plastic and paper funnels (the ‘She-Wee’) that have been manufactured to assist women to urinate in a standing position, but these should be practised before use in wilderness settings (45).


Vaginal Discharge or Itching

Wilderness conditions and inconvenient hygiene can lead to a change in a woman’s vaginal flora, presenting as vaginal discharge or vaginitis.  During travel in the wilderness, the most common causes of vaginitis are yeast infections, bacterial vaginosis, and chemical irritation (45).  Women prone to yeast infections should bring their own over-the-counter medicine or get a prescription for fluconazole before travel (45).  For any concerning symptoms that persist, women should be encouraged to seek primary healthcare.

  

Considerations for the Individual:  Pre-deployment

  • Discuss new menstrual products and / or hormonal medications with a health practitioner before deployment.

  • Trial new menstrual products and / or hormonal medications well before departure and note their efficacy and any adverse side effects.

  • If you have a regular cycle, it may be worth trying a period tracker app for a few months prior to travel to understand your typical menstrual cycle.


Considerations for the Leader:  Pre-deployment

  • Consider what facilities will be available and what will need to be catered for.

  • Plan at least 3 comfort breaks per day as well as before and after the day’s activities and communicate that to the group.  Knowing what explicitly to expect each day will alleviate a lot of problems. 

  • Incorporate briefings outlining facilities and disposal of waste menstrual products into the standard pre-departure planning for all team members.

  • Recognise that this may be the first time your clients, colleagues or participants may be travelling to remote locations and may not have the knowledge or confidence to deal with their periods confidently and effectively.   Have an open conversation with them and afford them the opportunity to share any concerns.

 

Considerations for the Individual:  In-Country

  • Contraception:  Some people may find that menstruation stops entirely with some hormonal medications, the coil or implants, but note that some can take 3-6 months for side effects such as breakthrough bleeding, period frequency, or amenorrhea to settle.

    You may find that they need to try several options to find one that works for them, so this process should begin several months ahead of any anticipated fieldwork. 

  • Period delay medications:  These can delay menstruation by a few days to weeks.  The advantage is that this is a short-term measure meant to delay a particular period, so may be useful for people who don’t normally want to take hormonal medications and would not affect fertility. 

    You will typically take the medication a 2-3 days before the onset of menstruation and keep taking it until you’re ready for your period to start.  Your period should then start 2-3 days after stopping the medication and will mark the first day of your new cycle.  You can take this medication when needed but bear in mind that there can be side effects which vary by the individual.

    This technique is only really appropriate for shorter trips of up to two weeks.

  • Menstrual cups are an intravaginal device (worn inside the vagina much like a tampon) and are made from medical-grade silicone.  The advantage over disposable hygiene products is that these can comfortably be worn for up to 12 hours, meaning most field days can easily be achieved without having to change products.

    The length of time you can wear your cup without having to change will also depend on how heavy your menstrual flow is.  Different brands will have different capacities but can typically hold up to 30ml liquid.

    In terms of infection, an independent study showed that a menstrual cup did not amplify the Staphylococcus aureus toxin when tested in vitro (49) and another study (50) found less bacterial growth obtained from cultures of the used cup than from cultures of used tampons or pads.  No published case reports of toxic shock syndrome have been associated with menstrual cup use.  (51)

    Several randomized controlled trials compared tampons with menstrual cups, and in one study of women aged 19 to 40 years, a significant difference in overall satisfaction was found.  Most women stated that they would continue to use the cup (91%) and that they would recommend it to others (91%).  There was no difference between the groups in urovaginal symptoms. (51)

    In a recent study set in a low-income setting, the menstrual cup was rated significantly better for comfort, quality, menstrual blood collection, appearance, and preference.  (52)

    Menstrual cups will leak if over-full so consider liners or period underwear in addition, especially if you are susceptible to heavy flows.

    Menstrual cups should be rinsed in a basin or sink and reused.  After each cycle, they can be sterilised using boiling water for 7-10mins (brand dependent).  This means that they can be used even when camping deep-field, do not generate waste and will last the whole duration of the trip. 

  • Period underwear:  Reusable and washable menstruation underwear.  These can be worn all day without being changed and don’t contribute to any waste.  Multiple pairs can be used and washed over a menstrual cycle but once full they will need to be washed before they can be used again.  They therefore may not be ideal without washing facilities or if privacy whilst washing them is desired.

    Period underwear can also be used as a contingency for other tools such as menstrual cups or tampons. 

  • Disposable hygiene products:  If you prefer disposable hygiene products then there is no reason to change whilst in remote environments.

    As well as your usual items consider wet wipes, hand sanitiser and tissues with a few ziploc bags to facilitate changing pads and tampons.  Also consider Nappy Bags or Dog Poo bags as an alternative, being scented and opaque.

  • Contingency:  Even if people on hormonal menstrual control do not usually or frequently have periods, it’s worth taking some hygiene products and plastic bags in case of breakthrough bleeds. 

 

Considerations for the Leaders:  In-Country

  • Not everyone is able to take hormonal contraceptives or medication to stop or control their periods, for a wide variety of reasons and hormonal contraceptives do not always stop bleeding. Do not assume it is a simple case of taking medication.

  • Provide and label washing facilities exclusively used to wash and sterilise reusable menstrual products and ensure that people have space and privacy do to so.

  • Disposable items will need to be disposed of appropriately; the majority of products are not biodegradable and will need to be incinerated.    Non-biodegradable products will not degrade, may attract animals as other waste might (although menstruating women do not attract bears, that is a myth (53, 54)) and could pollute water sources.

  • Leaders could consider having an emergency supply of materials available and making it clear that these are easily available.

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