The Evolution of the Vulva and Vagina: A Lifelong Journey

Your vagina and vulva will change huge amounts from birth to old age.

Your vagina and vulva in the womb and as a newborn

To develop as a biological female, a few things have to happen. There are some deviations to these general rules in intersex people and those with differences in sexual development.

In a typical scenario, when you are conceived as a biological female, you get an X chromosome from both parents. It is the sperm that is designated either female or male.

The ovaries start to develop, which makes hormones that stimulate the growth of the uterus, fallopian tubes and vagina, while the external genitalia also develop – the vulva and vestibule.

At birth, the vulva looks swollen, with well-developed labia minora (inner labia). This enlarged labia is due to the effect of the mother’s oestrogens, which can take weeks or months to disappear from the infant’s body.

Bacterial colonies also exist in the vagina in infancy because oestrogen stimulates vaginal cells to produce glycogen, a food source for healthy vaginal lactobacilli bacterial species. Without food, these colonies do not exist. A baby girl has bacterial colonies like a fertile-age woman (her mother, specifically).

A baby girl may even bleed a little from the vagina when this oestrogen disappears. This is called withdrawal bleeding and occurs when oestrogen is suddenly withdrawn.

Anyone on hormonal birth control actually experiences withdrawal bleeding as their ‘period’. This bleeding is not a real period but due to the sudden withdrawal of the hormones during the seven-day sugar pill phase.

A baby girl will not develop pubic hair since this is the activity of the adrenal glands, not the ovaries. The vaginal opening can be seen between the labia, with thick mucous covering the vaginal opening, plus the hymen, a thin membrane covering the vaginal opening.

The hymen has small openings to allow fluid to be dispersed. The hymen is a leftover from when the two halves of the body joined together.

The vagina and vulva in childhood

During childhood, the vagina may be protected by the hymen and has very little going on.

Very few bacteria are present since increases in bacterial numbers (healthy bacteria) are determined largely by the presence of oestrogen (and thus glycogen) – bug food.

The mons pubis and outer labia fat pads diminish, leaving the clitoris and labia minora (inner labia) standing out more. Because there is very little oestrogen, the vulva tissue looks thin and pale red or pinkish, as blood vessels show through.

Labia may stick together, known as labial adhesion. The pH of a child’s vagina is alkaline or neutral, which is more like a menopausal woman. Irritation is, therefore, more common in children from bubble bath and toilet paper dye.

The vulva and vagina at puberty

The adrenal glands start to produce androgens, which causes girls to start to have body odour and pubic hair, and acne can start to appear. This is also about when kids tend to start being more interested in each other with crushes and kisses.

Due to the impact of testosterone on the clitoris, nipples and vagina, masturbating may become more interesting.

Then, a year or two later, the ovaries kick into gear, and girls start to grow breasts. Eventually, the first period will arrive as the final wave of puberty’s magic wand.

The vulva will change in appearance, with the inner labia growing longer, maybe wrinkly, and darker in colour. Hips widen, and the fat pads on the mons pubis and labia majora return.

With the return of oestrogen also comes the return of vaginal microflora, which is fed on glycogen produced by vaginal cells.

The vulva and vagina in the reproductive years

The whole puberty shebang takes about four years to complete, from the ages of 8-9 and 16. Hair grows around the pubic area and armpits, breasts develop, hips widen, and menstruation starts and keeps going – for a while.

The vulva and vagina during pregnancy

The vulva and vagina change during pregnancy. After about six or eight weeks, the blood volume has increased across the body, so mucous membranes start to look bluish or violet in colour.

Pressure can also cause veins to enlarge, forming harmless but maybe uncomfortable varicose veins around the vagina and vulva.

Connective tissue softens in the vulva and perineum to allow for birth, while the vaginal walls produce thicker mucous, loosen off connective tissue, and increase muscle fibre size. There is an increase in the length of the vaginal walls, which may cause some bulging of the front vaginal wall.

Lactobacilli are at their height, and anaerobic bacterial colonies decrease, keeping the vagina acidic and pathogens to a minimum. A thick, white discharge, which may have a yellowish hue due to the effects of progesterone, may be present.

Any watery discharge during pregnancy needs to be checked, as it may indicate fluid loss.

During birth, the vaginal walls expand dramatically, allowing the baby to travel outside the body. This expansion is due to the rugae – folds – that open up like pleats.

After birth, the fourchette (bottom join of the vagina nearest the anus) is flattened. Any cuts (episiotomy) or tears during delivery may have stitches and can leave a small scar on the perineum.

Each of you will have unique changes to your vulva and vagina immediately after birth, and you will heal and return to a new version of normal.

The rugae return to normal after about three weeks, with the vagina gradually shrinking back to more or less prepregnancy dimensions.

Bacterial colonies also change, most likely due to the abrupt hormone change. To breastfeed, you need prolactin levels to be high, which is the opposing hormone to oestrogen. This switch in dominant hormone may allow pathogens to sneak in, so being hygienic and diligent after birth is important.

It’s advised to avoid sex for six to eight weeks at least, but most women will find it takes much longer for full healing to occur, and the desire to have sex to return.

The vulva and vagina in perimenopause

Perimenopause is the period of time as you transition into menopause. There is no defined time frame for this, but your forties is usually about when it begins, with perimenopause typically lasting no more than four years.

Some people will go through early menopause, genetic or induced by surgeries or treatments for health conditions. The ovaries slow down their production of oestrogen, which also reduces healthy bacterial colonies over time.

You may experience a change in the look and function of the vulva and vagina with the impact of less oestrogen.

First, progesterone drops, leaving just oestrogen, which may make you feel like you are in a state of PMS all the time – cramping, bloating, and tender breasts.

Then, oestrogen slows, which causes hot flashes, memory interruptions, heart palpitations, headaches, and vaginal dryness.

Then, you hit menopause, and it all grinds to a halt.

The vulva and vagina in menopause

Most women will enter menopause before they turn 55. The vulva and vagina will change as the fat deposits again disappear, just like in childhood, and the skin becomes thin and dry.

Labia minora may shrink away, with the vaginal opening – the introitus – becoming smaller. Pubic hair may turn grey and thin out. The cells of your vagina become less active and robust, resulting in greater opportunity for damage.

Vaginal pH will become less acidic, usually sitting at around 5.0. The urethra and bladder start to lose robustness, and infection or other symptoms may appear more easily.

These are named the genitourinary symptoms of menopause – GSM (formerly atrophic vaginitis). Sex may become painful; however, one of the best ways to keep your vaginal cells active is to use them! Those with active sex lives have much healthier vaginas into older age.