The menstrual cycle: more than just a bit of bleeding
Let me take you through the different stages of your cycle.
Follicular phase: fifty shades of period blood
It all starts on ‘Day 1’ – this is the first day of your period – and the bleeding usually lasts for three to eight days (on average five). Bleeding is classically heaviest on Day 2.
The blood during your period can come in a huge range of shades and hues. It won’t look the same as the blood you see when you cut your finger, because it’s not just plain blood. It’s mixed with mucus and cells from the inside of the uterus and the reason there is blood in the first place is because the juicy lining that’s built up over the month contains an intricate network of blood vessels that were meant to feed that elusive pregnancy it was planning on accommodating. The colour also depends on the time taken for the blood to come out. Just as an apple goes brown when it is cut and left exposed to the air, so blood starts to darken and, ultimately, go brown or almost black if it’s left to hang around for long enough.
It’s not uncommon for a period to start as spotting. This means light bleeding that’s not really enough to need a pad. It can be pinkish, which is usually due to the lining starting to fall away, or various shades of brown, which means it’s coming out very slowly or could even be old blood from your last period. Don’t be overwhelmed by this; it’s normal. New red bleeding tends to be thinner and often a bit watery because it’s the freshest. It can get a bit thicker and more crimson in colour because it has had a bit of a wait before show itself. Then normally it becomes quite light and turns brown to black before it stops completely. A wide range of colours is completely normal and to be expected.
The blood that’s being shed will clot in the uterus, so your body has to make anticoagulants – chemicals to break them down – in order to re-liquify the blood, so it can flow out. Many women tell me that ‘pieces of liver are coming out’. Admittedly, clots may look pretty sinister, but it’s not always something to worry about. If the amount of blood present exceeds the speed at which your body can make these anticoagulants you may experience clots, which can escape through your cervix, which softens slightly to allow the blood to escape. Clots tend to be small, usually no bigger than the size of a fifty-pence coin. However, larger clots, and lots of them, are a sign that there’s heavy bleeding going on, so it’s worth visiting your GP to check it’s not causing anaemia, to consider treatment and whether there’s an underlying reason, many of which are covered in Chapter 5.
While you’ve been busy concentrating on the outward manifestations of your period, you may not have realised that your brain has been busy making hormones: GnRH (gonadotrophin-releasing hormone), LH (luteinising hormone) and FSH (follicle-stimulating hormone). GnRH is produced first by the hypothalamus and then signals to the anterior pituitary to release LH and FSH, which then stimulate the ovary to prepare an egg for release (ovulation) and to produce oestrogen, which starts to rebuild the endometrium, in preparation for the hope of a pregnancy during this new cycle. Eventually, there is a massive surge in LH release, which triggers ovulation. LH is what you are trying to detect with the ovulation sticks that you can buy if you’re trying to get pregnant and want to work out when you’re ovulating. A patient once proudly told me that she usually ovulates about three times per month because her ovulation sticks told her so. You cannot ovulate more than once during a single menstrual cycle, although you can release more than one egg, which is how you get non-identical twins. This is one of the quirks of ovulation sticks; they tell you when you have had an LH surge, which can happen several times in one cycle, but they don’t confirm you popped out an egg.
Luteal phase: eggs and shells
Eggs live in sacs called ‘follicles’ which undergo several months of maturation before they can get to the stage of being released. Ovulation marks the start of the luteal phase and is like a Hollywood audition; at the start of your cycle there may be ten eager, willing candidates, but as time goes on, only one is selected to go forward and become the ‘dominant follicle’, which grows and grows, forming a cyst which pops on about Day 12–16 of the cycle, throwing it on to the main stage in the hope of being fertilised. It’s not unusual to get a bit of pain at this point. Ovulation itself is an inflammatory process and the ovary producing the ‘star egg of the show’ can get slightly enlarged which itself causes pain; then, when the cyst bursts, it leaks a little bit of fluid into your pelvis which can be uncomfortable. This ovulation pain (also called ‘mittelschmerz’, German for ‘middle pain’) can be sharp or like toothache, really low down near your hip bone on one side, but it usually lasts only twelve to twenty-four hours. Many women are quite anxious about this kind of pain and are horrified by the idea of a cyst bursting in their tummies. But it’s a positive sign that their bodies are working the way they should, which reassures most people. There may also be a little bit of bleeding at this time; ovulation bleeding only happens in about 3 per cent of cycles,2 but it’s certainly nothing abnormal that you need to worry about. It happens due to a momentary drop in oestrogen.
After the egg is released, a shell of the original follicle, called the ‘corpus luteum’ is left behind in the ovary, which starts to release progesterone – the pro-pregnancy hormone. One of its main roles is to ensure the lining is fully preened and plumped up for the arrival of a fertilised egg. Progesterone levels are at their highest seven days after ovulation, and if fertilisation has not occurred, the corpus luteum eventually throws its hands up in the air and says, ‘I can’t do this any more. I’m bored of pumping out all this progesterone to no avail. I’m out of here!’ It then slowly starts to degrade, and this causes a drop in both oestrogen and progesterone, which means the growth of the endometrium is no longer supported, so it begins to fall away. This is your period and the cycle starts again.
Variations in cycle length
It’s normal for there to be some variation in the length of your menstrual cycle on a month-to-month basis.
A lot of mums of teenage girls contact me online, worried that there is something wrong with their daughters because they are only having periods every two or three months. But this is quite common when your periods start because the hormone cycles are still synchronising, and also coming up to the menopause when you have fewer eggs left, meaning you’re less likely to ovulate as easily. Cycles are typically shortest and most regular in your twenties and thirties. Any variation in the length of the cycle at any age will be due to changes in the follicular phase because the length of the luteal phase is pretty standard being dictated by the lifespan of the corpus luteum.3 (See Chapter 4 for other factors affecting cycle length besides age.)
Menstrual cups, tampons, pads … ?
There are an overwhelming number of ‘menstrual-hygiene’ products on the market; I’m not hugely keen on the term because I think it perpetuates the myth of periods being ‘dirty’.
Menstrual cups, tampons, pads … I’m constantly asked which are ‘the best’, and, to be honest, from a health point of view there is no shining star – so I’d advise you to use whichever makes you feel most comfortable.
Menstrual cups
There may be a few furrowed brows at the mention of ‘menstrual cups’. If you are wondering, they are small and egg-cup-shaped and made of a soft silicone, which you insert into your vagina, where they sit collecting blood as it comes out of the cervix. There’s only one small study that has ever compared tampons and cups head to head and actually found greater satisfaction with cups compared to tampons,