Pregnancy is a life-transforming journey and while there is so much changes that happens during this time, you cannot always be prepared for everything. Here are 10 surprising facts that you did not know were true during pregnancy.

The Nesting Instinct

If you have seen animals look for paper scraps, or take fur out of their own body or collect small twigs and stem to build a nest for their upcoming babies, even if the animals are domesticated, humans do the name. Humans do not take fur or hair out of their body, but we too experience a powerful urge to prepare our home for the baby. We clean it, decorate it and thanks to modern homes, we can now baby proof it do!

Mommy Brain

This happens in the first trimester, when tiredness, morning sickness and other symptoms can make the mother feel worn out and mentally fuzzy, often called the mommy brain. The National Institutes of Health also notes that cognitive function decline in the third trimester of pregnancy, leading to memory problems.

Mood Swings

Premenstrual syndrome (PMS) and pregnancy share several symptoms, such as breast swelling and tenderness, hormonal fluctuations, and mood swings. If you’ve experienced severe mood swings due to PMS, you may notice an intensification of these emotions during pregnancy. It's common to feel joyful one moment and tearful the next as your body adjusts to hormonal changes.

Breast Growth

An increase in breast size is one of the earliest signs of pregnancy apart from your missed period. It happens in the first trimester due to the higher levels of hormones like estrogen and progesterone. The growth continues throughout pregnancy.

Skin Changes

Have you heard about pregnancy glow? This happens because pregnancy women have an increased blood volume, this happens to provide extra blood flow to the uterus and other organs, especially the kidneys. This greater volume brings more blood to the vessels and increases oil gland secretion.

Hair and Nails

During pregnancy, many women notice changes in their hair texture and growth. Hormonal shifts can make hair grow faster and reduce hair loss. However, these changes are typically temporary, and many women experience some hair loss during the postpartum period or after they stop breastfeeding. In some cases, hair growth may also occur in unexpected areas like the face, belly, or around the nipples. Additionally, hair texture can shift, becoming drier or oilier, and some women even notice a change in hair color.

Nails can also undergo changes during pregnancy. Increased hormone levels may cause nails to grow faster and become stronger, but for some women, nails may become more brittle, splitting and breaking more easily. Like hair changes, these nail changes are usually temporary. If your nails are more prone to splitting or tearing, it’s helpful to keep them trimmed and avoid exposure to chemicals in nail polish and nail polish remover.

Your Feet Grow

If you have heard about it, then you already know that it is not just the clothes that do not fit you, it is your shoes too. Extra fluid in the pregnant body also leads to swollen feet. The joints also tend to be looser during pregnancy.

Joint Mobility

Your body also releases hormones like relaxin that prepares your body, especially the cervix for the birth. This loosens the ligament in your body, which may make you less stable .

Varicose veins, constipation, and hemorrhoids

Varicose veins, common in the legs and genital area during pregnancy, result from blood pooling in veins enlarged by pregnancy hormones. They often disappear after delivery. To prevent them, avoid prolonged sitting or standing, wear loose clothing and support hose, and elevate your feet when seated.

Hemorrhoids, which are varicose veins in the rectum, may develop due to increased blood volume and uterine pressure. They can cause pain, itching, bleeding, or stinging, especially during bowel movements. Constipation, caused by hormonal changes and uterine pressure on the large intestine, can worsen hemorrhoids by straining during bowel movements.

Prevent constipation and hemorrhoids by eating a fiber-rich diet, staying hydrated, and exercising regularly. If needed, consult your doctor about stool softeners, laxatives, or creams for relief.

Labor and what goes out of your body

When you are in labor, your amniotic sac, that has fluid that surrounds the baby, breaks or ruptures, which is what is also known as water breaking. For most women contractions start before their water breaks, if not, then the doctor may have to rupture the amniotic sac, in case the cervix is already dilated. Some women may feel the urge to pee, while for some it may feel a trickling their leg.

Globally, one in six people of reproductive age experiences infertility at some point in their lifetime. Smoking is one of the key reasons for infertility among men and women worldwide, according to a new World Health Organization (WHO) knowledge summary.

The report, the 12th in a series of Tobacco Knowledge Summaries, highlights evidence linking tobacco use to infertility in women, harmful effects on sperm and sexual function in men, and potentially lower chances of success with some fertility treatments. It also warns that second-hand smoke may affect reproductive health.

Infertility is defined as the failure to achieve pregnancy after 12 months or more of regular unprotected sex.

What Does the WHO Report Say?

Infertility can have multiple causes. However, cigarette smoking and exposure to second-hand tobacco smoke are associated with infertility in women.

The harmful effects of cigarette smoking on women’s reproductive health are well documented, while evidence on other tobacco products, including waterpipe and smokeless tobacco, as well as nicotine products such as e-cigarettes, is still emerging.

Current data suggest potential risks to fertility, but further research is needed to fully understand these effects. Among

men, cigarette smoking is associated with harmful effects on semen and sperm, as well as sexual function, which can contribute to infertility.

On the other hand, women who quit smoking may have a lower risk of infertility compared with women who continue to smoke.

WHO recommends that healthcare providers inform individuals and couples planning pregnancy about the reproductive risks of tobacco use and offer evidence-based support to help them quit.

How Smoking Affects Fertility?

“Smoking is an important fertility consideration for both men and women. It can affect the quality of both eggs and sperm, and the concern is not limited to people who smoke themselves,” Dr Neelam Suri, Senior Consultant, Obstetrics & Gynecology, Indraprastha Apollo Hospital, Delhi, told HealthandMe.

Smoking also accelerates follicular depletion, which may contribute to an earlier onset of menopause compared with women who do not smoke.

Second-hand smoke can expose individuals to harmful substances that may affect reproductive health. Eggs and sperm are rapidly developing cells, and exposure to tobacco smoke can increase the risk of DNA damage and other cellular changes that may affect fertility and reproductive outcomes.

Dr Shalu , Senior Clinical Director, Cloudnine Group of Hospitals, Gurugram, told HealthandMe that while passive smoking may not directly cause infertility in every individual, regular exposure to tobacco smoke can affect reproductive health and have significant implications during pregnancy.

These include ectopic pregnancy, miscarriage, preterm birth, pre-eclampsia, fetal growth restriction, low birth weight, stillbirth, placental complications and neonatal complications.

Regular exposure to second-hand smoke may also potentially influence the chances of success with fertility treatments such as IVF.

“This is particularly relevant for couples undergoing IVF, where egg and sperm quality can influence the chances of successful treatment,” Dr Suri said.

What Should Couples Planning Pregnancy Do?

For couples planning a pregnancy or undergoing fertility treatment, avoiding tobacco smoke is an important step towards protecting reproductive health.

This means quitting smoking and maintaining a smoke-free environment at home to reduce regular exposure to cigarette smoke.

At the same time, fertility depends on multiple factors. Exposure to second-hand smoke does not necessarily mean a couple will experience infertility or IVF failure. However, reducing preventable risk factors can be beneficial when trying to conceive.

Ideally, couples should create a smoke-free environment before conception rather than waiting until fertility difficulties emerge.

Tylenol is one of the most commonly used pain killers. That’s why a study on the drug’s long-term effect on reproductive health of unborn girl children is concerning.

Researchers in Denmark found that girls exposed to paracetamol, also known as acetaminophen or Tylenol in the US, during fetal development had smaller ovaries, fewer ovarian follicles and smaller uteruses in infancy compared to girls who were not exposed to the component.

It’s essential to understand that study does not show that girls exposed to the drug will certainly have fertility problems later in life.

The researchers say it is still too early to know whether the changes observed during infancy and adolescence will translate into reduced fertility or earlier menopause.

What Did The Study Find?

Published in Human Reproduction Open, the study involved 302 girls from the Copenhagen Analgesic Study, or COPANA.

The researchers tracked mothers' paracetamol use during pregnancy through repeated questionnaires and also measured the drug in urine samples.

The girls were examined at around three months of age, during a period known as minipuberty, when the reproductive hormone system becomes temporarily active.

Of the 302 girls, 92 had first been exposed to paracetamol before 17 weeks of pregnancy; 67 were first exposed from 17 weeks onward and 143 had no reported prenatal exposure.

The researchers found that girls exposed during early fetal development had an approximately 40% smaller ovarian volume and a 13% smaller uterine volume compared to girls who were not exposed.

Girls exposed during mid-to-late fetal development stage had about 23% fewer ovarian follicles. These follicles contain immature eggs that can potentially develop and mature over a woman's reproductive life.

Additionally, girls exposed exclusively during early pregnancy also had lower levels of anti-Müllerian hormone (AMH), a hormone produced by ovarian follicles that is commonly used as a marker of ovarian reserve.

Also read: Tylenol, Other Medications Linked To 400% Rise In Liver Injuries In US

Changes From Infancy To Adolescence

Researchers also examined an independent group of 1,210 girls who had been followed from infancy through adolescence.

In this group, prenatal paracetamol exposure was associated with a smaller uterus at puberty and smaller ovaries during adolescence.

Study leader Margit Bistrup Fischer of Rigshospitalet in Copenhagen stressed that the long-term implications remain unknown. Whether these early reproductive differences affect fertility or the timing of menopause will require long-term follow-up.

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Tylenol And Infertility

This was an observational study, which means that researchers looked at an association between prenatal exposure to paracetamol and changes in future reproductive health.

They did not randomly assign pregnant women to take paracetamol, so the study cannot establish that the drug itself caused the changes.

The authors also say that external factors cannot be completely excluded. Women who took paracetamol because they must have been pain and discomfort due to headaches, fever or other illnesses. These underlying conditions could also influence fetal development.

Also, the women used relatively low to moderate amounts of paracetamol. According to COPANA cohort, the most common reasons were headaches or migraines, musculoskeletal pain, illness or cold and fever.

The study also found that increased reported paracetamol exposure, meaning high dose, was too associated with lower ovarian and uterine volumes.

Also read: Paracetamol Is Not Safe For Older People, Finds Study

Earlier Studies That Raised Similar Concerns About Tylenol

It's not the first time that Tylenol has sparked safety concerns. In 2025, new studies by Mount Sinai and Harvard T.H. Chan School of Public Health raised an concerning question: is prenatal exposure to acetaminophen associated with neurodevelopmental disorders including autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) in children?

A study led by Andrea Baccarelli, dean of Harvard T.H. Chan School of Public Health’s faculty of environmental health in BMC Environmental Health, systematically reviewed 46 previous studies encompassing data from more than 100,000 participants.

The aim was to investigate whether acetaminophen use during pregnancy correlates with neurodevelopmental disorders in children.

Applying the Navigation Guide Systematic Review method—a strict, gold-standard approach to assessing environmental health evidence—the study team evaluated the quality, risk of bias, and strength of evidence of all included research.

By doing so, it was possible to conduct a solid synthesis of available scientific literature, and what emerged was a pattern: better-quality studies showed a more pronounced association between prenatal acetaminophen exposure and offspring increased risk of ADHD and autism.

Another recent study observed that liver injuries reported to US poison centres increased by nearly 400% between 2000 and 2024, due to acetaminophen, sold under brand names like Tylenol.

The study also found that exposures involving acetaminophen-containing combination drugs decreased by 60%-85% after the US Food and Drug Administration capped the amount of acetaminophen allowed in combination prescription products.

However, harmful exposures to acetaminophen alone increased steadily over the 24 years. The findings suggest that regulatory action reduced liver injuries linked to combination products, while acetaminophen alone remained a leading contributor to poison-centre-reported liver injuries.

Are your kids completely safe inside the classroom? A new study has raised concerns about the air quality in classrooms, particularly the bacteria that could result in reduced lung function in children.

Recent research presented at the European Respiratory Society (ERS) Congress in Barcelona, Spain intended to ensure that schools have completely healthy environments for children, particularly their developing lungs.

Classrooms Have High Levels Of Two Harmful Bacteria Groups

The study was presented by Dr. Soutrik Banerjee from the Department of Environmental and Prevention Sciences, University of Ferrara, Italy, and French technology company, Alten S.A.

Researchers from the University of Ferrara in Italy and French technology company Alten analysed data from the SINPHONIE project, which examined indoor environmental conditions in multiple schools across Europe.

The analysis is based on nearly 300 classrooms across 22 European countries. Researchers measured the levels of Streptomyces and Mycobacterium in classroom dust and compared this with lung function in children using spirometry, a standard test to measure breathing and respiration health.

The researchers adjusted their analysis for several factors that could affect lung function, including children's age, sex, body mass index, exposure to second-hand smoke, pet allergens, socioeconomic factors, age of the school building, region and local outdoor air pollution.

They found that children in classrooms with higher levels of Streptomyces had a 0.08-litre lower forced vital capacity (FVC).

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What Is Forced Vital Capacity?

Meanwhile, higher levels of Mycobacterium were associated with a 0.06-litre lower FEV₁ and a 0.13-litre-per-second lower peak expiratory flow (PEF). FEV₁ measures how much air can be exhaled in the first second of a forceful breath, while PEF measures the fastest rate at which air can be expelled.

Dr Banerjee told the Congress, “We know that indoor air quality in schools can be affected by pollutants, humidity, ventilation, temperature, dampness and biological agents like fungi and bacteria. However, much less is known about whether the types of bacteria growing in classroom dust are linked to children’s lung function.”

“We were particularly interested in two bacterial groups, Streptomyces and Mycobacterium spp., which are found in soil, dust and water systems. We wanted to see whether higher exposure to these bacteria in the classroom is associated with children’s lung health across Europe.”

Also read: US Newborns Are Missing A Crucial Vitamin K Shot Which Can Lead To Brain Bleeding

How Dangerous Are These Bacteria?

Both Streptomyces and Mycobacterium are present widespread in the environment. They are found in soil, dust and water systems. The study did not show that children developed a bacterial disease because of classroom exposure.

Instead, researchers are investigating whether exposure to the bacteria could influence the airways and thereby their lung function.

One possibility is that they could irritate the respiratory tract or activate immune and inflammatory pathways. Another is that the bacteria may simply be markers of other problems inside a classroom, like excess moisture, poor ventilation, inadequate cleaning or outdoor dust entering the building.

Dr Soutrik Banerjee, from the University of Ferrara, said: “The bacteria may either have a direct biological effect, or they may be indicators of other indoor environmental factors that influence lung function.”

A small reduction in a lung function measurement does not automatically mean that a child has lung disease. Lung function naturally varies between children according to age, height, sex and other factors. The differences reported in this study were modest for individual children, according to the researchers.

However, Banerjee said the findings could still matter at a population level because children are repeatedly exposed to school environments. “Children are exposed to school indoor environments every weekday, and a mild to moderate reduction in lung function today may be a precursor to preventable lung disease in later life,” he said.

How Can This Be Prevented?

The European Respiratory Society specifically cautioned against taking extreme measures like sterilising classrooms.

Professor Alexander Möller, Head of the ERS Paediatric Assembly and Professor of Paediatric Pulmonology at the University Children's Hospital Zurich, who was not involved in the study, said: “The practical message is not that schools should become sterile environments.”

But he pointed that adequate ventilation, control of dampness and mould, regular cleaning and proper building maintenance could help.