The incidence of temporary or early menopause after chemotherapy or radiotherapy varies according to the age of the person, pubertal status, her existing ovarian reserve, type of chemotherapy, radiotherapy field and the cumulative dose of chemotherapy or radiotherapy.

The risk of menopause increases with age, most likely because older women have decreased ovarian reserve compared to younger women.

Chemotherapy combined with radiotherapy is associated with an increased risk compared to chemotherapy alone.

Chemotherapy with alkylating agents, such as cyclophosphamide, is associated with the greatest risk of menopause (>2 fold increased risk).

Use of taxanes or anthracycline/ eprirubicin based regimens are associated with a 26% and 49% increased risk of menopause respectively.

Tamoxifen is also associated with a 48% increased risk of menopause.

Use of newer agents such as bevacizumab and tyrosine kinase inhibitors may also be associated with an increased risk of early menopause.

Use of adjuvant gonadotrophin-releasing hormone agonists (GnRHa) with chemotherapy is associated with increased recovery of menstruation. However, it is unclear whether fertility is also preserved.

What are the symptoms?:

1. Hot flushes/flashes
Hot flushes are among the most common. They cause someone to become hot, sweaty suddenly, and flushed, especially in the face, neck, and chest. Some females also experience chills.

2. Night sweats
Night sweats are hot flushes that occur at night. It appears that falling oestrogen levels can affect the hypothalamus, which regulates body temperature.

3. Irregular periods
Throughout the menopausal transition, it is normal to have irregular or missed periods. Eventually, a female will stop having periods entirely. 

4. Mood changes
Mood changes are unpredictable shifts in mood that are not related to life events. They can cause someone to feel suddenly sad, weepy, or angry. Mood changes are common during perimenopause and menopause.

5. Breast soreness
Breast tenderness is another common symptom of menopause, though its frequency tends to decrease in the later stages.

6. Decreased libido
Menopause also commonly affects libido or desire for sex. This can be the direct result of having lower testosterone and oestrogen levels, which can make physical arousal more difficult. However, it can also be a secondary result of the other symptoms of menopause, such as mood changes or a side effect the hormonal blockers.

7. Vaginal dryness
As female sex hormones ensure a good circulation of blood around the vagina, a lack of them can decrease blood flow and, therefore, natural lubrication. This may cause dryness, which can be uncomfortable or make penetrative sex more difficult.

8. Headaches
Someone entering menopause may experience more frequent headaches or migraine episodes due to a dip in estrogen. This can be similar to the headaches that some women experience before a period.

9. Tingling extremities
During menopause, some females experience tingling in the hands, feet, arms, and legs. This symptom results from hormone fluctuations affecting the central nervous system and typically only lasts for a few minutes at a time.

10. Burning mouth
A burning mouth is another potential symptom of menopause and may manifest as a feeling of burning, tenderness, tingling, heat, or numbing in or around the mouth. This is another result of hormonal changes. The mucus hormones in the mouth have sex hormone receptors, which decrease with a decline in oestrogen. This can contribute to pain and discomfort.

11. Changes in taste
Some females may notice changes in their sense of taste, with more robust flavours, during menopause. They may also experience a dry mouth, leading to a higher risk of developing gum disease or cavities.

12. Fatigue
Fatigue can be a distressing and sometimes debilitating menopause symptom. This could be the result of lower quality sleep due to hot flushes and night sweats or the result of hormonal fluctuations themselves.

13. Bloating
Women can experience bloating during menopause for several reasons. They may experience water retention, gassiness, or slower digestion as a result of stress. If they change their eating habits around this time, they may also experience bloating.

14. Other digestive changes
Female sex hormones influence the microbes a person has in their mouth and digestive tract. This can mean that during menopause, a female's gut flora changes in composition. They may notice changes in their digestion or that they react differently to certain foods.

15. Joint pain
Oestrogen helps decrease inflammation and keep the joints lubricated. As a result, some women experience joint pain because of reduced estrogen. Oestrogen regulates fluid levels throughout the body, so when the body becomes low in this hormone, women are more prone to joint aches or menopausal arthritis.

16. Muscle tension and aches
Women going through perimenopause or menopause can also experience muscle tension or aches. This is because of the same factors as menopausal joint pain.

17. Electric shock sensations
Women can experience sensations that resemble electric shocks during perimenopause and menopause. It is not clear what causes this, but it may result from changing hormone levels in the nervous system.

18. Itchiness
Because oestrogen is related to collagen production and skin hydration, a decline in this hormone can lead to increased itchiness or dryness, both around the vulva and elsewhere on the body.

19. Sleep disturbance
Sleep can become lighter or disrupted for many reasons during menopause. Women may frequently wake because of night sweats, wake up earlier, or find it challenging to get to sleep.

20. Difficulty concentrating
A decline in oestrogen can sometimes cause mental fogginess or difficulty concentrating. Hot flashes and sleep issues may also contribute factors.

21. Memory lapses
As with concentration and focus, menopause can also affect memory. Again, this could directly result from lower oestrogen levels or compromised sleep.

22. Thinning hair
During menopause, hair loss or thinning is another result of ovarian hormonal fluctuations. This causes the hair follicles to shrink, meaning that hair grows more slowly and sheds more easily.

23. Brittle nails
During or after menopause, the body may not produce enough keratin, which is the substance that nails need to stay strong. This can lead to brittle, weak nails that crack or break easily.

24. Weight gain
Females can gain weight due to several factors during menopause. A decline in oestrogen can cause weight gain, as can lower amounts of physical activity. Mood changes can also mean that a female eats differently.

25. Stress incontinence
Stress incontinence refers to a frequent or sudden urge to urinate. Some people also refer to it as an "overactive bladder." This symptom is common during menopause, as changes in hormone levels can cause the bladder and pelvic muscles to become weaker.

26. Dizzy spells
The hormonal changes that occur during menopause affect insulin production, making it difficult for the body to maintain blood sugar stability. This is the main reason that some females experience dizzy spells during perimenopause and menopause.

27. Allergies
Some females report new or worsening allergy symptoms when they experience menopause. This happens because, during menopause, females can have spikes in histamine. Histamine is the chemical that causes allergic reactions.

28. Osteoporosis
During perimenopause, a decline in oestrogen can also result in a loss of bone density. In severe cases, this can lead to osteoporosis, which causes the bones to become more fragile and break easily.

29. Irregular heartbeat
Some women may experience an irregular heartbeat, or arrhythmia, during or after menopause. 

30. Body odour
Hot flushes and night sweats can cause an increase in body odour during menopause. If a woman often feels stressed or anxious, they may also notice that they are sweating more.

31. Irritability
Because of hormonal fluctuations or the impact of other menopause symptoms, females going through this change may find that they feel irritable. Stress or a lack of sleep may also contribute to this.

32. Depression
For some women, hormonal imbalances may trigger depression. However, in this case, depression is often situational and may not be long term. A lack of sleep and stress can contribute to this. Sometimes, menopause may trigger depression or low mood because of the change it signifies in a female's life. Any significant life change can play a role in depression, even if the change is positive.

33. Anxiety
Anxiety is another mood-related symptom that some women experience during menopause. It may worsen at night or only occur intermittently as hormone levels fluctuate. As with menopause-related depression, this anxiety may be situational and improve once hormones level out.

34. Panic disorder
In some cases, women may experience panic attacks during menopause. When these attacks occur unexpectedly or suddenly, they can show a panic disorder. This may happen because of hormonal changes or the fear of feeling anxious itself.

Having menopause and cancer at the same time can be very distressing. Managing your health, your illness and menopause all at the same time is difficult, given that your treatment options for menopause are often limited. However, there are many things you can do that can help you.

References:

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2. Spears N, Lopes F, Stefansdottir A, et al. Ovarian damage from chemotherapy and current approaches to its protection. Human Reproduction Update 2019; 25(6): 673-93.

3. Gargus E, Deans R, Anazodo A, Woodruff TK. Management of Primary Ovarian Insufficiency Symptoms in Survivors of Childhood and Adolescent Cancer. Journal of the National Comprehensive Cancer Network 2018; 16(9): 1137-49.

4. Chemaitilly W, Li Z, Krasin MJ, et al. Premature Ovarian Insufficiency in Childhood Cancer Survivors: A Report From the St. Jude Lifetime Cohort. The Journal of Clinical Endocrinology & Metabolism 2017; 102(7): 2242-50.

5. Zhao J, Liu J, Chen K, et al. What lies behind chemotherapy-induced amenorrhea for breast cancer patients: a meta-analysis. Breast Cancer Research and Treatment 2014; 145: 113+.

6. Zavos A, Valachis A. Risk of chemotherapy-induced amenorrhea in patients with breast cancer: a systematic review and meta-analysis. Acta Oncologica 2016; 55(6): 664-70.