Hair loss after childbirth happens because pregnancy hormones paused the normal hair shedding process during pregnancy, so the hair loss is actually your hair cycle 'catching up' with its normal process several months postpartum.

Telogen effluvium is a common, temporary type of hair loss that can be triggered by severe stress, illness, or other body changes like childbirth—it pushes as much as 70% of hair into its resting phase, causing hair to fall out.

Humans may have as many as 100,000 to 150,000 individual hairs on our scalps, growing at a rate of roughly 1 centimeter per month.

40% of women will have noticeable hair loss by age 50.

Real-time tracking of individual hair cells has revealed that hairs don't actually get pushed out from the root—instead, hair cells are tugged upward by surrounding tissues that act like tiny motors.

We're typically born with all the hair follicles we'll ever have, just as women are born with all their eggs.

A pregnant woman's brain sheds gray matter, perhaps explaining 'baby brain.'

Male pattern baldness is not solely inherited from the maternal side; its causes are still under investigation, but scientists think the genetic component of this type of hair loss involves multiple genes.

Postpartum psychosis is an emergency requiring immediate psychiatric intervention, with symptoms including hallucinations, paranoia, and delusions that may put a baby at risk.

Postmenopause is a stage lasting roughly a third of a woman's life

Postmenopause is the final stage of menopause, occurring once a woman hasn't had any vaginal bleeding for a full year. She is then considered postmenopausal for the rest of her life. While some of the intense symptoms she might experience during postmenopause will decline, her risk for certain conditions and diseases will increase.

Male pattern baldness accounts for more than 95% of hair loss in men and is characterized by thinning hair, hair loss, and a receding hairline.

Modern pregnancy tests detect a specific hormone in a woman's urine or blood.

Menstruation, which occurs monthly, is the release of an unfertilized egg

This routine vaginal bleeding is part of a woman's hormonal cycle and occurs after an egg is released by an ovary during ovulation and isn't fertilized. Also known as periods, this monthly occurrence can cause a number of symptoms, including cramping, fatigue, and mood changes.

Women experience heightened bone loss after menopause

Both women and men begin to lose some bone density after age 35, on average. But, for the first decade after menopause, women lose bone more rapidly due to the significantly decreased levels of estrogen, putting women at heightened risk of osteoporosis and related bone fractures.

Postpartum depression typically starts in the weeks following childbirth, and the disorder can keep someone from performing tasks of daily living.

Humanity's reduced body hair slows down wound healing

Cuts to human skin take twice as long to heal compared to chimps and other mammals. Scientists argue this is due to the reduced number of hair follicles on human bodies. Hair follicles contain stem cells which help repair skin cells faster, so as humanity shed its hair over time, so to speak, it also slowed its wound healing.

It's been about 30 years since a new hair loss drug was approved in the US, and women currently have no approved pills for hair loss.

Late-stage clinical trials indicate that a common arthritis drug may be a promising treatment for a leading cause of hair loss.

In 1909, a top public health official in America wrote in an academic journal that baldness was caused almost exclusively by snug-fitting hats.

A man’s genes can predict his hairline

There’s actually some truth to the idea that you should look at your mother’s father. But genetic research tells us that the full picture is somewhat more complicated. An interesting read on how to use genetics to figure out if you'll go bald (with illustrations).

Stress contributes to gray hair because when the body experiences stress, the sympathetic nervous system releases specific hormones that influence pigment-producing cells.

Pregnancy causes a woman's blood volume to increase by up to 50%.

So-called 'recession blondes and brunettes' skip hair appointments to save money

One hairstyle trend is seen as a recession indicator: people letting their hair grow darker roots instead of frequently splurging on expensive blonde highlights.

Your feet can expand—permanently—due to pregnancy.

How menopause affects mental health

Menopause, a natural biological process, occurs in three stages: perimenopause (hormone fluctuations), menopause (end of menstrual cycles), and postmenopause (12 months without menstruation). Hormonal shifts during this time can affect neurotransmitters, increasing the risk of mood disorders.

Cleopatra purportedly recommended grinding up fly heads and rubbing them on areas experiencing hair loss as a treatment.

Understand the complex, biological journey of pregnancy with this science explainer.

Every organ in a mother's body changes during pregnancy as her body produces hormones that relax muscles, allowing for the needed expansion.

'Weight cycling'—when someone repeatedly loses and gains weight—can harm an individual's metabolism.

'Menobelly' is real, with more fat stored around the abdomen as estrogen levels drop.

What happens during the first eight weeks of pregnancy?

The first weeks of embryonic development, known as embryogenesis, are one of the most critical phases during pregnancy. This simple breakdown from the Khan Academy illustrates what we know about how the complex process unfolds.

Perimenopause, which typically occurs in a woman's mid-40s, precedes menopause

Sometimes referred to as the menopausal transition, perimenopause often lasts around four years as the ovaries' production of the reproductive hormones progesterone and estrogen decline. It may be accompanied by mental and physical symptoms, including irregular periods, hot flashes, sleep issues, mood swings, and alterations to a woman's sex drive.

Heightened sense of smell during pregnancy is not yet well understood

Boosted smell powers and strong reactions to them are often reported beginning around the six-week mark of pregnancy. Researchers say hormonal changes likely play a role, but the change remains poorly understood.

When people stopped using GLP-1, they regained two-thirds of the weight back.

Nasal congestion is a common side effect of pregnancy, called pregnancy rhinitis

In one recent study, almost 100% of pregnant women experienced this condition in their third trimester. The congestion is likely due to hormonal changes and neurophysiological factors, and it may also worsen at night due to circadian factors and gravitational redistribution when lying down. Treatments include saline nasal irrigation and the use of nasal strips to widen the nasal valve area.

Late-onset menopause lowers osteoporosis risks, but heightens the risks for certain cancers

Defined as when a woman starts to experience perimenopause after age 55, late-onset menopause is linked to an elevated risk of developing breast, ovarian, and uterine cancers.

Menopause is defined as 12 months without a period

Menopause is officially when a woman stops getting her period, meaning she has stopped ovulating and can no longer get pregnant. A woman has to go a full year without bleeding or spotting to know she has hit menopause.

Women are born with all the eggs they will ever produce in their lifetimes

Girls are born with an estimated 1 million to 2 million eggs in their bodies, but around 10,000 die monthly before girls hit puberty. Scientists have not yet figured out why there's such an excessive number of eggs prior to menstruation, but they've calculated that there are roughly 300,000 to 400,000 eggs left at puberty.

Scalp cooling caps may help prevent hair loss during chemotherapy by temporarily reducing blood flow to the scalp, thereby reducing the amount of chemotherapy that reaches hair follicles.

Treatment-induced menopause is menopause induced by surgery or medicine

Chemotherapy and radiation, as well as oophorectomy (a surgical procedure to remove one or both ovaries) and a radical hysterectomy, can cause a woman to become menopausal. Women who go through medical menopause experience the same symptoms as women who go through menopause caused by natural hormonal cycles.

A baby's due date is calculated from the first day of the last menstrual period—not when sexual intercourse occurred.

Menopause hormone therapy infuses the body with estrogen after the body's natural levels drop

The treatments can treat symptoms like hot flashes and vaginal dryness at varying doses. Progestogen, another hormone, is also typically prescribed with estrogen because estrogen alone can thicken the uterus lining, which elevates the risk of developing endometrial cancer.

Premarin, the hormone medication derived from pregnant horses, is 'PREgnant MARes urINe'

Scientists in the late 1920s and early 1930s discovered estrogens could be extracted from human placenta, and then isolated it from the urine of pregnant women. But researchers discovered the urine of pregnant horses had similar substances and the horse product was much easier to collect in significant amounts—leading to Premarin.

Pregnancy makes someone more attractive to the mosquito species that transmits malaria.

It's never too late to start hormone replacement therapy for menopause symptoms because the products may help alleviate symptoms of menopause or fight bone loss.

Fetal development, week by week

Gestation is the period of time between conception and birth when a baby grows inside the mother's womb. Changes occur constantly over the course of these 40 weeks. At week 17, for instance, the skeleton of a fetus begins changing from soft...

Perimenopause can last as long as 8 years

Perimenopause typically lasts about four years, beginning at around age 45; however, some women experience it as early as their 30s. Smoking and thyroid disease are factors that can trigger early perimenopause. Early menopause, which can increase health risks, occurs in about 5% of women. Researchers are still investigating why it occurs.

Early menopause, occurring before age 45, can be triggered by certain risk factors

Some potential causes of early menopause include autoimmune disorders, chemotherapy, smoking, and certain surgeries that cause the body to produce lower levels of estrogen and progesterone.

Explore how the placenta acts as lungs, kidneys, and more in the womb.

Explore this week-by-week visualization of pregnancy

This graphic illustrates how development proceeds during each week of pregnancy, tracking what shifts and milestones typically occur during each stage of the process. It also includes typical weights of the fetus throughout.

Menopause is a hormonal transition point, like puberty

Yet menopause isn't talked about as much. In this podcast episode by Houston Methodist, a Texas-based hospital, the host speaks with a gynecologist with a specialization in menopausal medicine about what menopause really is, and how women and the people in their lives can navigate this next life stage.