Every year, Delhi and northern states battle hazardous air during the winter months of October to January due to plummeting temperatures, smoke, dust, low wind speed, vehicular emissions and crop stubble burning. This time, experts say that the condition is likely to get worse in the coming days.

Pregnant women who live in polluted environments are more likely to experience preterm labor, which raises the risk of low birth weight, undeveloped lungs, and infant mortality during or after birth.

Delhi recorded the worst air quality in India on Wednesday with a severe AQI of 418 while Noida and Gurugram also faced very poor levels.

Air pollution in India's national capital increased to 'severe' on an official index on Wednesday for the first time this season as temperatures and wind speeds dropped, reducing visibility and affecting some flights.

The air quality index (AQI) had surged to 366 according to real-time data from the Central Pollution Control Board (CPCB) at 9 am.

The toxic smog that has enveloped India's capital worsened on Wednesday morning as temperatures dropped and the seasonal winter haze set in, reducing visibility in some areas and possibly affecting flights.