If you're struggling to sleep, feeling anxious, suddenly getting more spots than you used to and you're in your late 30s onwards, it could be down to the hormone progesterone, or more specifically, the dip in the female hormone that starts in perimenopause.
"Progesterone is the lovely calming hormone which is important for mood, sleep and skin," says Dr Tania Adib, a consultant gynaecologist who practices at the The Medical Chambers in Kensington, London. Integrative hormone doctor Terry Loong goes so far as to describe progesterone as "a natural antidepressant."
But progesterone is one of the first hormones to tail off in mid-life and it often catches women unawares especially as we may still be having regular periods. At this life stage, it's easy to put being extra snappy or wired down to simply having a lot on our plates rather than the first inklings of menopause. "We often find this in women who are still having periods – they are still producing oestrogen, but not progesterone," says Dr Adib. "They experience anxiety, insomnia, agitation, they become really irritable and they sometimes get acne."
When it comes to female hormones, oestrogen seems to take centre-stage, but understanding progesterone and what it does throughout your reproductive life from puberty to period, contraception to perimenopause is vital. Here's what you need to know.
What is progesterone and what does it do?
Progesterone prepares you for pregnancy
Like oestrogen and testosterone, progesterone is a sex hormone. Its job is to thicken the lining of the womb and support the pregnancy, says Tania. It's produced in the ovary just after you ovulate. "When you release an egg, you are left with the remains of the sack on the ovary that holds a maturing egg before it’s released, called the corpus luteum and that produces the progesterone which will support the pregnancy in the first three months until the placenta takes over."
If there is no fertilised egg, progesterone levels drop and your period starts.
Progesterone is a 'natural antidepressant' and helps you sleep
If you've ever had sleeplessness just before your period, the natural dip in calming progesterone could be why. "Progesterone is a mood calming hormone," explains integrative hormone doctor Dr Terry Loong. "It acts as a natural antidepressant, enhances mood and relieves anxiety."
It also has a calming effect on the brain because it stimulates the brain's GABA receptors, the feel-good, calming neurotransmitters which help with maintaining sleep, Dr Terry adds.
Progesterone calms the skin
Its calming powers work on your skin too as progesterone is a natural testosterone inhibitor (testosterone can make your skin more oily leading to blocked pores). When progesterone dips we might start experiencing hormonal acne. "Our hormones work in sync and if one is out of balance this impacts on our skin, " says Dr Terry.
What about the progesterone-only mini pill?
The POP or progestogen-only pill (e.g. Lovima, Hana) is in the news this month as it's just been licensed by the MHRA to be available over the counter in pharmacies after a consultation, not purely via your GP.
You might think that if it's the job or progesterone to support pregnancy, why would you use it as a contraceptive? It's the terminology that's confusing here, says Dr Tania. You may sometimes still see the mini-pill referred to as 'progesterone-only', but it's actually a similar-sounding but very different thing called progestogen or progestin. "Progestin, as in the mini-pill, prevents the sperm from entering the uterus because it thickens the mucus," says Tania. What's more, it thins the lining of the womb making it unsuitable for pregnancy. "It can stop ovulation as well but that’s not its main mechanism," she adds.
Progesterone and progestin/progestogen "are completely different molecules and they act in completely different ways," she clarifies.
What causes low progesterone symptoms?
You’re going through perimenopause
As we mentioned, this is the biggie that affects all women. As we approach perimenopause (normally in our 40s) and menopause, (average UK age 51) our sex hormones decline, with progesterone first in line.
"Progesterone is often the first hormone to drop and can cause symptoms such as insomnia, changes in your menstrual cycle, hot flashes, night sweats, palpitations and fatigue," says Dr Sophie Shotter, an aesthetic doctor who also prescribes hormone replacement therapy.
You have a medical condition
If you're not yet perimenopausal, your levels of progesterone may be lower than normal for other reasons. "Low progesterone can be caused by other medical conditions such as hypothyroidism and polycystic ovarian syndrome ( PCOS ). These conditions all cause infrequent ovulation which in turn lowers progesterone,” says Dr Sophie.
Low progesterone – what are the signs and symptoms?
There are many low progesterone symptoms, including those we've mentioned affecting our sleep, skin and mood, that suggest your progesterone levels aren't quite where they should be.
"You may also have abdominal pain, breast tenderness, spotting between periods, vaginal dryness, depression or mood swings, low libido, low blood sugar and headaches or migraines," says Dr Sophie. Blood testing can help to provide a definitive diagnosis, however this is generally not available on the NHS, explains Dr Sophie. "It would not be the sort of blood test you could just ask your GP to run out of curiosity, but if, for example, you were having recurrent miscarriages, it would be justified."
Is low progesterone dangerous?
Not in itself, no. "The natural decline of progesterone is a normal part of the changes that happen to our reproductive system over time and is not dangerous or harmful to our health," reassures gynaecologist and obstetrician Dr Ellie Rayner.
We can live healthily with low levels. "If the symptoms don't bother you, then it isn’t an issue," says Dr Sophie.
However, lack of sleep can have many knock-on effects and is often something that women, as in the case of Liz Earle, wellbeing expert and author of The Good Menopause Guide find they can't live with. "For me, pretty much my only symptom of menopause was sleep disturbance and that was the one that sent me booking the doctor’s appointment," Liz told us. "As a busy working mother of five, I can handle most of what life throws at me – but only if I get a good night’s sleep!" says Liz. "When that started to go, I sought professional help."
If you're trying to get pregnant, it's advised to seek help if you think your levels may be low. It's progesterone's job to support first-trimester pregnancy, and low levels are associated with miscarriage, says Dr Terry.
What can we do about low progesterone?
1. Take hormone replacement therapy
( HRT ) is the most common treatment for low progesterone. "Using HRT we can restore optimal levels," says Dr Sophie Shotter. It replaces the progesterone that we have lost. There are many different forms of HRT such as oral tablets, vaginal pessaries or a coil-like device that is inserted into your uterus.
Natural body identical progesterone (Utrogestan) in combination with natural estradiol (oetsrogen) is the safest form of HRT, says Dr Tania. "It does not increase your risk of breast cancer above your already one in eight risk as a woman getting older," she says.
Progestin, the same substance as in the mini pill may also be prescribed as HRT (you'll see it as norethisterone, which is also available on prescription as period delay tablets) in patches such as Evorel Conti, a combined oestrogen (estradiol) and progestogen patch. But Dr Tania doesn't recommend it. "Taking progestin in combination with estradiol does increase your risk of breast cancer, which is why I wouldn’t use a progestin unless it's the only thing that works for a woman. Then I would say there that is a higher risk of breast cancer with this."
Dr Tania recommends natural progesterone called Utrogestan, which comes as either a vaginal pessary or an oral tablet. However, if you suffer from disturbed sleep, you'll only get the sleepy benefits from the oral form. "The liver metabolises the progesterone into metabolites which act on GABA and they help the sleep effect. If it’s taken through the vaginal skin it’s not metabolised by the liver, it’s just absorbed directly," she explains.
Lastly, progesterone is important in HRT to protect the womb lining. Taking oestrogen on its own as HRT increases the risk of womb (uterus) cancer, sometimes called endometrial cancer, a ccording to the NHS Inform.
2. Keep your weight healthy
"Maintaining a healthy weight can help with low levels of progesterone," says Dr Sophie. "Excess weight boosts oestrogen levels, therefore causing an imbalance with progesterone."
3. Minimise stress
Easier said than done, but decreasing stress levels can help, as the production of stress hormones can trigger the kidneys to convert progesterone to cortisol, says Dr Sophie. Avoiding over-exercising can help too, as again this minimises stress hormone production.
5. Eat progesterone-boosting foods
Some foods will also boost the body’s production of progesterone, such as beans, broccoli, Brussels sprouts, cabbage, cauliflower, kale, nuts, pumpkin, spinach and whole grains, Dr Sophie says. "Some foods such as bananas, cabbage, shellfish and walnuts also decrease the body’s oestrogen levels helping to regulate the oestrogen: progesterone balance."
6. Take progesterone-supporting supplements
Some supplements can support the production of progesterone. Dr Terry recommends magnesium, vitamin C, vitamin B6, zinc and vita agnus castus. "These will support ovulation and production of progesterone, but will not replace progesterone in the same way HRT does, so when there are no more eggs (e.g. in menopause) to ovulate, no amount of supplements will help with low levels.”