Imagine this. A young teenager, 17, years old, who is fully developed. Now imagine this, the same teenager has a fully developed extra set of limbs and a pelvis. That extra set of pair is attached with chest artery. But, how can this happen?

While it is extremely rare, and has a chance of less than one case occurring per 100,000 births. Such things do happen. This is called parasitic twin.

What Is A Parasitic Twin?

It is an extremely rare type of cojoined twin where a baby is born with an underdeveloped twin attached to its body. This condition is also known as vestigial twins. The condition is very closely related to conjoined twins, where babies are connected at birth and share organs. However, the main difference is that in conjoined twins, there are two developed babies, whereas in parasitic twins, only one is fully developed, other one is underdeveloped and non functional.

In such a case, the twin who is developed is medically known as the autositic or the dominant twin. The dominant twin is healthy in most aspect but may have extra tissue, organs, or limbs from the parasitic twin.

The parasitic twin may be attached with the dominant twin through several places. The common joints are at the head, torso, chest, pelvis, buttocks, or back. In these cases, the parasitic twin is not alive and they die either in the womb or during the childbirth.

Doctors Remove Parasitic Twin

Now, let's go back to the case we referred to, where a young teenager had an extra pair of limbs attached to chest. The teenager who has not been named is from Uttar Pradesh's Unnao neighbourhood, and was treated in AIIMS, Delhi. The team of doctors successfully removed the extra set of limbs from his body.

Dr Asuri Krishna, who led the team of specialist who surgically removed the extra limbs told the BBC that only 40 to 50 cases of parasitic twins have been documented in world medical literature, and in those cases, the surgery had been attempted on children. The doctor said that without much medical literature to guide them, the team of doctors depended on "intuition, skill and knowledge".

The doctor shared that the child had two fully formed legs, buttocks and external genitalia, which weighed around 15kg "protruding from his abdomen".

How Was The Surgery Performed?

The doctor shared that first they identified how interconnected the parasitic and host twins were. The doctors took scans and found that parasitic twin was attached to the teen's breastbone. The blood was being supplied from a vessel in his chest. However, "there wasn't much connection with other main organs like the liver or kidneys," said Dr Krishna. The team also found a large cyst in the teen's abdomen.

Then the surgery was performed in two stages. In the first stage, the parasitic twin was removed. Then the cystic mass was extracted from the surrounded area. The entire surgery was completed in two and a half hours and the team of doctors included radiologists, anaesthetists, and plastic surgeons.

The biggest challenge was when the teen's blood pressure dropped as 30 to 40% of his blood flowed to the parasitic twin, however, the doctors were prepared for it and they stabilized him.

Delhi's air quality deteriorated sharply after Diwali celebrations, with several monitoring stations recording 'Severe' pollution levels on Monday, November 9. As firecracker emissions added to the city's existing pollution burden, concerns are mounting over the impact of toxic air on children's respiratory health.

For children, prolonged exposure to polluted air can be particularly concerning. What may initially appear to be a seasonal cough or minor throat irritation could become more serious if coughing persists or is accompanied by wheezing and breathlessness. Children with asthma or other respiratory conditions may be especially vulnerable, as poor air quality can aggravate their existing symptoms.

But how can parents distinguish a routine cough from a warning sign of respiratory distress? When should they seek medical attention, and what precautions can help protect children? HealthandMe spoke to pulmonologists to understand the symptoms parents should watch for and when to worry.

How Should Parents Respond If A Child Develops Coughing Or Wheezing?

Also read: Delhi AQI Crosses 2,000 Mark After Diwali: What Happens To Your Body Within Hours Of Exposure?

If a child develops a cough or wheezing, the first step is to minimise further exposure to polluted air.

Dr Nikhil Rajvanshi, Consultant – Pediatric Pulmonologist, Allergy and Sleep Specialist at Rainbow Children's Hospital, Delhi, advises parents to avoid outdoor play, running and strenuous physical activity when AQI levels are high.

Parents should also keep windows closed during peak pollution periods, use a HEPA air purifier if available, and ensure children wear a well-fitted N95 mask if they are old enough to tolerate it safely.

For children with diagnosed respiratory conditions such as asthma, following their prescribed treatment plan is important.

"If the child has a diagnosed respiratory condition such as asthma, parents should follow the prescribed action plan and administer inhalers or nebulisation only as advised by their doctor. Inhaled medication should never be started or discontinued without medical guidance," Dr Rajvanshi told HealthandMe.

He also cautioned against routinely giving children antibiotics or over-the-counter cough and cold medicines without consulting a paediatrician.

Warning Signs Of Breathing Trouble Parents Should Not Ignore

A cough does not always indicate a serious respiratory problem, but certain symptoms need prompt medical assessment.

Dr Rajvanshi said parents should watch for:

• Rapid or laboured breathing.
• Visible pulling in of the chest or ribs while breathing.
• Flaring of the nostrils.
• Persistent wheezing.
• Difficulty speaking or feeding because of breathlessness.
• Unusual drowsiness.
• Bluish or grey discolouration of the lips or tongue.

A child who is struggling to breathe, has pauses in breathing or develops bluish lips needs emergency medical care. Infants below three months with a temperature of 38°C or higher also require prompt medical assessment.

Read More: Delhi Becomes World's Most Polluted City Ahead Of Diwali, Says Swiss Agency: Experts Recommend Precautions

Coughing Or Wheezing: How Can Parents Tell The Difference?

One important distinction parents should understand is that wheezing is not simply another form of coughing.

Dr Rajvanshi explained that wheezing is a whistling sound, usually heard while breathing out, and may indicate narrowing of the airways.

Recurrent wheezing, night-time coughing or coughing that worsens during physical activity should be evaluated by a paediatrician rather than dismissed as a seasonal cough.

He also emphasised that good nutrition can support a child's general immunity but cannot replace appropriate respiratory treatment. Reducing pollution exposure, recognising symptoms early and seeking timely medical attention remain important.

How Can Families Protect Themselves From Poor Air Quality?

Dr Kuldeep Kumar Grover, Associate Director – Pulmonology and Critical Care at CK Birla Hospital, Gurgaon, said an appropriately fitted N95 or FFP2 respirator offers better protection against fine particulate matter than a cloth or surgical mask.

However, the mask must fit snugly around the nose and mouth, without gaps.

He advised people to avoid outdoor running, brisk walking, cycling and strenuous exercise during periods of high pollution, as increased breathing rates can lead to greater inhalation of pollutants.

Children, older adults, pregnant women and people with asthma, COPD or heart disease should be particularly cautious and minimise prolonged outdoor exposure.

At home, families should keep windows and doors closed when outdoor pollution is high, use a HEPA air purifier where possible, and maintain good indoor ventilation when outdoor air quality improves.

People with asthma or other chronic respiratory conditions should continue their prescribed medication and keep their rescue inhalers accessible.

"Anyone experiencing severe breathing difficulty or chest pain should seek immediate medical attention," Dr Grover told HealthandMe.

He added that air pollution can affect even healthy individuals, so precautions should not be limited to those with pre-existing respiratory conditions.

"The objective is not to stop stepping outdoors altogether, but to make informed decisions about when, where and how long we expose ourselves to polluted air," he said.

Delhi's air quality took a nosedive after Diwali celebrations on Sunday. Smoke from firecrackers contributed to the already soaring pollution across the national capital.

Some real-time air-quality platforms reported readings above 1,000, while some claims of levels crossing 2,000 also surfaced . Meanwhile, the city's official Central Pollution Control Board (CPCB) AQI reached the 'severe' category at several monitoring stations.

India's official AQI scale runs from 0 to 500. Anything above 400 is classified as severe. A reading above 2,000 was reported by independent real-time air quality platforms.

The staggering AQI has sparked numerous health concerns among those who are continuously exposed to the toxic air. Exposure to high concentrations of fine particulate matter like PM2.5 can trigger a number of health issues including respiratory and cardiovascular effects within a matter of hours. The effects may linger even after a person returns indoors.

What Happens Within The First Few Hours Of Exposure?

Also read: Delhi Becomes World's Most Polluted City Ahead Of Diwali, Says Swiss Agency: Experts Recommend Precautions

PM2.5 refers to particles measuring 2.5 micrometres or smaller. Because of their miniscule size, they can traverse deep into the lungs. Some particles can even enter the bloodstream.

According to the World Health Organization (WHO), these particles can affect multiple organs and increase the risk of respiratory and cardiovascular diseases. Within hours of exposure, people may experience:

• Irritation of the eyes, nose and throat
• Coughing, wheezing and shortness of breath
• Chest tightness or discomfort
• Worsening of asthma and other existing respiratory conditions

The UK's Department of Health and Social Care notes that symptoms of short-term air pollution exposure can start within hours or several days. People with asthma, chronic obstructive pulmonary disease (COPD) and heart conditions are vulnerable to such high concentrations of particulate matter.

The effects of polluted air are not restricted to the lungs. Fine particles can trigger oxidative stress and inflammation, potentially affecting blood vessel function and the cardiovascular system.

Experts say that that exposure to PM2.5 can affect heart rate regulation and blood vessel function within six hours.

Dr Viny Kantroo, Senior Consultant, Respiratory Medicine, Critical Care & Sleep Medicine Indraprastha Apollo Hospital, New Delhi, told HealthandMe, "Short-term exposure to high levels of particulate pollution can increase the risk of heart attacks and strokes. Fine particles can enter the bloodstream and contribute to inflammation, affect blood vessel function and increase the tendency for blood clots to form. The risk is higher in people with hypertension, diabetes or existing heart disease."

Effects Continue After You Return Home

Also read: Pregnant During Peak Pollution? A Trimester-Wise Guide to Safer Festive Celebrations

Inflammatory responses may continue even after exposure stops. It also depends on the pollution concentration, duration of exposure and an individual's underlying health.

Moving indoors reduces further exposure, but it does not instantly reverse the damages triggered by pollutants that you have already inhaled.

Airway inflammation and increased sensitivity can last for days, depending on the intensity and duration of exposure. People may continue to experience coughing, wheezing or breathing issues after leaving a polluted environment.

The US Environmental Protection Agency also notes that short-term particle pollution exposure can aggravate asthma and bronchitis and is also linked with cardiovascular events, including heart attacks and strokes, especially among people with existing heart disease.

How To Reduce Exposure After Diwali?

During severe pollution days, avoid outdoor exercise and avoid stepping out. If going outdoors is unavoidable, use a well-fitting N95 or N99 respirator rather than a cloth or surgical mask.

Dr Kantroo advised, "During severe pollution, they should avoid strenuous outdoor activity and continue their prescribed medicines."

At home, keep windows closed when outdoor pollution is high and use a properly sized HEPA air purifier, if available. Avoid adding to indoor pollution through incense, candles, mosquito coils or smoking.

People with asthma or other chronic conditions should follow their prescribed treatment plans. Seek medical attention for breathing difficulty, chest pain or worsening symptoms. Severe breathlessness or chest pain need urgent medical care.

Diwali is traditionally associated with celebrations, family gatherings, illuminated homes and the sound of festivities. However, for women who are pregnant, the festive season can bring an additional health concern that often goes unnoticed: deteriorating air quality. The combination of firecracker emissions, vehicular pollution, construction dust and seasonal changes can significantly increase the concentration of pollutants in the air, making it particularly important for expectant mothers to be mindful of their surroundings.

Pregnancy is a period of considerable physiological and developmental change. A woman's respiratory and cardiovascular systems undergo adaptations to support the growing baby, and exposure to pollutants such as fine particulate matter (PM2.5) can add to the body's environmental burden. These particles are small enough to penetrate deep into the lungs and trigger inflammatory responses. Research has associated maternal exposure to air pollution with adverse pregnancy outcomes, including preterm birth, low birth weight and babies being small for their gestational age.

However, this does not mean pregnant women need to withdraw completely from festive celebrations. The objective should be to make informed choices, reduce unnecessary exposure and understand how precautions can be adapted at different stages of pregnancy.

First Trimester: Prioritising Early Development and Reducing Exposure

The first trimester, particularly the initial 12 weeks, is a critical period of embryonic development, when major organs and body systems begin forming. During this stage, expectant mothers may also experience nausea, fatigue, dizziness and increased sensitivity to certain environmental triggers.

Exposure to firecracker smoke and heavily polluted environments should be minimised. Although an isolated exposure does not automatically indicate harm to the pregnancy, repeated or prolonged exposure to poor air quality is best avoided.

Women in their first trimester should consider the following precautions:

- Avoid standing near areas where firecrackers are being burst or smoke is accumulating. Even brief festive activities can result in unnecessary exposure when pollution levels are high.

- Check the local Air Quality Index (AQI) before stepping outdoors. Reschedule non-essential outdoor activities when air quality deteriorates.

- Avoid participating in activities involving firecracker lighting, including sparklers and other fireworks.

- Keep indoor environments as clean as possible by avoiding excessive incense, dhoop and other smoke-producing substances.

- Maintain adequate hydration, eat balanced meals and prioritise rest, particularly if experiencing pregnancy-related fatigue or nausea.

The first trimester is also when women should be particularly mindful of their overall health rather than attempting to maintain their usual festive routines at the cost of adequate rest.

Also read: Delhi Becomes World's Most Polluted City Ahead Of Diwali, Says Swiss Agency: Experts Recommend Precautions

Second Trimester: Balancing Mobility, Physical Activity and Environmental Safety

The second trimester is often considered a relatively comfortable phase of pregnancy. Many women experience a reduction in early pregnancy symptoms and may feel more energetic, making social gatherings and festive activities easier to manage.

However, feeling physically better should not translate into overlooking environmental risks. Continued exposure to fine particulate matter and other pollutants can affect maternal respiratory health and has been associated with adverse fetal growth outcomes.

A few practical adjustments can help women enjoy the festivities without unnecessary exposure.

- Choose indoor celebrations or smaller family gatherings instead of crowded outdoor events, especially in areas with visible smoke.

- Avoid evening walks or outdoor exercise when AQI levels are poor. Physical exertion can increase the volume of air inhaled, potentially increasing pollutant exposure.

- If outdoor movement is unavoidable, a properly fitted N95 mask may help reduce exposure to particulate matter. However, it does not eliminate all pollutants or replace the need to avoid heavily polluted environments.

- Keep windows closed during periods when outdoor pollution is particularly high. Ventilate the house when outdoor air quality improves.

- Continue pregnancy-appropriate physical activity as advised by the treating obstetrician, adapting the routine according to local air quality conditions.

Women should also avoid prolonged standing, excessive physical exertion and crowded spaces where access to clean air may be limited.

Also read: Can Prolonged Exposure To PM2.5 Increase The Risk Of Blood Clots And Stroke?

Third Trimester: Protecting Maternal Respiratory Health and Avoiding Physical Strain

During the third trimester, the growing uterus places additional pressure on the diaphragm, and many women experience breathlessness, fatigue, disturbed sleep and reduced physical mobility.

When these changes coincide with poor air quality, the importance of limiting exposure becomes even more relevant. Maternal exposure to air pollution has been associated with an increased likelihood of preterm birth and low birth weight, although these outcomes are influenced by several factors and cannot be attributed to a single exposure.

At this stage, the focus should be on maintaining comfort, avoiding unnecessary physical strain and ensuring timely medical attention when required.

Expectant mothers in their third trimester should:

- Avoid crowded firecracker celebrations, open-air events and prolonged exposure to smoke.

- Prefer celebrations at home or in well-ventilated indoor environments with cleaner air.

- Avoid lifting heavy decorations, climbing ladders or undertaking physically demanding festive preparations.

- Keep antenatal appointments on schedule and discuss any respiratory discomfort or concerns about pollution exposure with their obstetrician.

- Avoid unnecessary late-night outings, particularly when pollution levels tend to remain elevated.

Women experiencing persistent breathlessness, chest discomfort, wheezing or unusual fatigue should not dismiss these symptoms as routine pregnancy-related discomfort.

Beyond the Trimester: Five Air-Safety Habits Every Expectant Mother Should Follow

While pregnancy progresses through different developmental stages, the need to minimise pollution exposure remains consistent throughout all three trimesters. A few simple measures can make festive celebrations safer.

1. Make AQI checks part of your daily routine

Do not rely solely on visible smoke or haze to judge air quality. Check the local AQI through official monitoring platforms such as the Central Pollution Control Board before planning outdoor activities. Pollution levels can vary considerably between neighbourhoods and throughout the day.

2. Keep indoor air cleaner

Indoor spaces are not automatically pollution-free. Smoke from incense sticks, camphor, candles and firecrackers entering through open windows can affect indoor air quality. Avoid unnecessary smoke-producing activities and consider using a properly sized HEPA air purifier, if available.

3. Choose celebrations that do not involve firecrackers

Lighting diyas, decorating the home, preparing festive meals and spending time with family are meaningful ways to celebrate without adding to firecracker-related pollution. Staying away from areas where fireworks are being burst is particularly important.

4. Do not compromise on hydration and nutrition

A balanced diet containing seasonal fruits, vegetables and adequate protein supports maternal health. Drinking sufficient water helps maintain hydration, although neither hydration nor antioxidant-rich foods can neutralise the effects of inhaled pollutants.

5. Know when to seek medical attention

Persistent coughing, wheezing, chest pain, significant breathlessness, dizziness or other unusual symptoms warrant medical evaluation. Pregnant women with asthma or existing respiratory or cardiovascular conditions should discuss an individualised pollution-safety plan with their healthcare provider.

A Healthier Diwali Begins With Informed Choices

One of the biggest misconceptions surrounding pregnancy and pollution is that precautions are necessary only when air quality becomes visibly poor. In reality, exposure to particulate matter can occur even when the air appears relatively clear. This makes awareness and preventive action important throughout the festive period.

It is equally important to remember that pregnancy does not mean putting life on hold. Women can continue to participate in meaningful traditions, enjoy family gatherings and celebrate festivals by making sensible adjustments to their environment and activities.

There is no single trimester in which exposure to air pollution can be considered completely safe, and no precaution can eliminate exposure entirely. The emphasis should be on reducing avoidable exposure, following local air-quality advisories and seeking individualised medical guidance.

Diwali should be a celebration of light, happiness and togetherness. For expectant mothers, a little extra planning can help ensure that the festivities remain centred on what matters most: their health, comfort and the well-being of their growing baby.

By Dr Sudeshna Ray, Associate Director Obstetrician, Gynaecologist, Jaslok Hospital and Research Centre, Sr Consultant in Breach Candy & HN Reliance