What is a ‘flash period’?

What is a ‘flash period’?
The latest episode of And Just Like That… highlights the common perimenopause symptom

Women who have gone through perimenopause will find the latest episode of And Just Like That… quite familiar.

The episode shines a light on a specific symptom of perimenopause – a flash period. Perimenopause is a transitional time that ends with menopause.

In the Sex and the City reboot, Charlotte York Goldenblatt (Kristin Davis) is dealing with her daughter Lily’s struggles with using tampons for the first time, and says: “Just when I’m finally done with my period and I thought I would not have to deal with this s*** anymore.”

But when she turns around, the audience sees the colour red blooming in the groin area of Charlotte’s pristine white jumpsuit, prompting Carrie Bradshaw (Sarah Jessica Parker) to say her period “may not be as done as you think”.

Earlier in the episode, Charlotte revealed she hadn’t gotten her period in four months, so what gives? Why did she suddenly get her period despite being perimenopausal?

Fellow character Miranda Hobbes (Cynthia Nixon) refers to the phenomenon as a “flash period”, a period that comes suddenly due to irregular cycles.

An irregular cycle is one of the symptoms of perimenopause and is often the first sign that the body is entering the phase before menopause.

During perimenopause, oestrogen levels start to decrease and progesterone levels, which work in tandem with oestrogen for ovulation and menstruation, get thrown off balance.

This hormonal imbalance affects your period cycles. According to the NHS, the frequency of your periods may change, from having them every two to three weeks or not having them for months at a time.

You may also start having either unusually light or heavy periods.

However, these “flash periods” are not necessarily signs that you are ovulating again.

Dr Lauren Streicher, medical director of the Northwestern Medicine Centre for Sexual Medicine and Menopause, told TODAYthat during perimenopause, women are “generally not ovulating, but there’s enough oestrogen stimulation that you can get that buildup in the lining of the uterus and then when it gets to a certain level you start to bleed and it’s completely unexpected”.

The average length of perimenopause is four years, but some people may go through it for just a few months or, in some cases, up to 10 years, according to Harvard Medical School. It can start as early as your mid-thirties or as late as your mid-fifties.

Perimenopause ends when you have gone for more than 12 months without having a period.

Other symptoms of perimenopause include hot flashes, vaginal dryness, need to urinate more frequently, sleep problems such as insomnia, and changes in mood like irritability, depression and mood swings.