Is your period actually normal?

Yes, for the vast majority of women. The RCOG states that clots up to the size of a 50p coin (US quarter) are considered clinically normal. You should speak to your GP if you regularly pass clots larger than a 50p coin, if clotting is accompanied by very heavy flow that soaks through a pad or tampon every hour for several consecutive hours, or if the clotting represents a significant change from your usual pattern. (Source: RCOG Patient Information; NICE NG88)

A late period is one of the most common menstrual concerns, and in most cases does not indicate a serious problem. The most obvious cause to rule out is pregnancy. Beyond pregnancy, common causes include stress (which suppresses the hypothalamic-pituitary-ovarian axis), significant weight changes, excessive exercise, illness, travel across time zones, and changes to medication. Polycystic ovary syndrome (PCOS) is the most common hormonal cause, affecting approximately 1 in 10 women. If your period is occasionally a few days late, this is normal variation. If you miss periods entirely without being pregnant, a GP visit is worthwhile. (Source: ACOG; NHS guidance)

Some degree of period pain is experienced by 75-80% of women. Mild to moderate cramping on the first 1-2 days, relieved by over-the-counter painkillers, falls within the normal range of primary dysmenorrhoea. However, pain that regularly causes you to miss work or school, that is not controlled by standard painkillers, that worsens over time, or that is accompanied by pain during sex or bowel movements may indicate an underlying condition such as endometriosis, adenomyosis, or fibroids. Roughly 5-10% of women experience period pain severe enough to significantly interfere with daily activities. This is not something you should simply accept. (Source: ACOG; NICE)

Yes, significantly. Data from the SWAN study, which tracked over 3,300 women through the menopause transition, shows that cycle length can vary by 7 or more days in a given year for 30% of women aged 40-45 and 50% of women aged 46-50. Flow patterns also change: some women experience lighter periods while others experience heavier, more prolonged bleeding. Both patterns can be normal perimenopausal variation. However, very heavy bleeding, bleeding between periods, or bleeding after sex should still be investigated. (Source: SWAN study; ACOG)

Strictly speaking, no. A true menstrual period involves shedding the uterine lining, which does not occur during pregnancy. However, bleeding during early pregnancy is common and can be mistaken for a period. Approximately 15 to 25% of women experience some bleeding in the first trimester, caused by implantation bleeding, cervical changes, or less commonly ectopic pregnancy or early miscarriage. Implantation bleeding is usually lighter than a normal period, shorter in duration (one to two days), and may be pink or brown rather than red. If your apparent period was lighter or shorter than usual and there is any chance of pregnancy, a home pregnancy test is the simplest way to clarify.

Premenstrual dysphoric disorder (PMDD) is a severe form of PMS affecting an estimated 3 to 8% of women of reproductive age. While PMS causes mild to moderate symptoms in the luteal phase, PMDD involves symptoms severe enough to significantly impair daily functioning and relationships. The key distinguishing symptoms are intense mood disturbances: severe irritability or anger, marked anxiety, significant depressive symptoms, and sudden mood swings. To meet diagnostic criteria (DSM-5), symptoms must be present in most cycles over the past year and must resolve within a few days of menstruation starting. Treatment options include SSRIs, hormonal contraceptives, and cognitive behavioural therapy.

Cycle syncing is the practice of adjusting exercise, nutrition, and lifestyle habits to align with the four phases of the menstrual cycle: menstruation, follicular, ovulation, and luteal. The concept is based on the fact that oestrogen and progesterone fluctuations affect energy, mood, appetite, and exercise capacity. The scientific evidence is mixed. It is well established that these hormonal fluctuations exist and that they affect physiology. However, large-scale clinical trials specifically testing cycle syncing protocols are limited. What is reasonable to say: paying attention to how you feel at different points in your cycle is a sensible practice. Claims that cycle syncing treats medical conditions outpace the current evidence.

The average is 28 days, but only 13% of cycles are exactly that length. The ACOG defines normal as 21 to 35 days, and FIGO's updated 2018 definition is 24 to 38 days. Cycles shorter than 21 days or longer than 38 days are considered outside the typical range and may warrant investigation, particularly if the pattern is consistent. Cycle length also varies with age: teenagers and women approaching perimenopause tend to have more variable cycles, which is physiologically expected. If your cycle is 32 days, you have likely been incorrectly told it is long. It is well within the normal range. (Source: Bull et al. 2019; ACOG)