Page 3 â Measuring time in different cultures. Measuring time. Scientifically, the year is a complete cycle of seasons. A year is when the earth completes one full orbit of the sun. Its length is measured from one spring equinox to the next spring equinox. Measuring the time of year was important to most people. Knowing the season was vital when deciding to plant and harvest crops as well as managing livestock in colder climates.
Experts have believed for a long time that pregnancy weakens a womanâs immune system, making her more susceptible to illnesses like the flu. However, research released just before the start of this flu season indicates that, in the case of the flu, the opposite may be true during pregnancy.
When a woman is pregnant, hormones suppress her immune system, making it harder to overcome infections such as that caused by salmonella. This can also have adverse effects on the fetus. Salmonella is a bacteria that infects humans after coming into contact with animal waste, usually via raw or unpasteurized foods.