Climate change and the environment

There has been an unprecedented surge in awareness of and engagement with the climate emergency and its impact on the environment and humans, especially on human health. (Consider that Time magazine selected 16-year-old Swedish climate crisis activist, Greta Thunberg as Person of the Year.) Climate change and its effect on the environment is not just reflected in increased temperatures and change in extreme climates, but it also includes other ways in which it can influence human health such as exposure to unsafe elements, lack of food and safe drinking water, poor sanitation, population migration, changing disease patterns and morbidity, more frequent extreme weather events, and lack of shelter. Pregnant women, before, during, and after pregnancy, and the developing fetus are considered the most vulnerable members of our species and may have increased sensitivity to the effects of climate change.

Environmental risk factors impact fertility and pregnancy problems

Over the last years, information about environmental risk factors impacting fertility and pregnancy problems has increased.  The negative impact of the environment on issues such as infertility, low birth weight, prematurity, and fetal and infant death has become more clear. 

In June of 2020, JAMA published a systematic review of 57 of 68 studies including a total of 32 798 152 births, which reported that there was a statistically significant association between heat, ozone, or fine particulate matter and adverse pregnancy outcomes.  The findings suggest that exacerbation of air pollution and heat exposure related to climate change may be significantly associated with a risk to pregnancy outcomes in the U.S.

Read more on air pollution and pregnancy outcomes here.

Certain health conditions, social and economic factors, and certain behaviors or exposures can increase the risk of adverse fertility, reproductive and pregnancy, and birth outcomes. 

This effect on the health of mothers, fathers, and babies in utero, for example, has prompted the American Congress of Obstetricians and Gynecologists (ACOG) to call for stricter policies concerning environmental chemicals.

Impact of climate change, global warming, and temperatures on fertility and pregnancy

Climate change has many different impacts on the environment. When trying to conceive and during pregnancy, increasing temperatures can decrease your fertility, lower sperm counts.

Studies have shown that elevated temperatures can lead to decreased fertility and births, and an increased risk of preterm births. 

Scientists have also reported that climate changes and an increase in global temperatures that are a symptom of climate change could lead to lower sperm counts.

Stress and fertility

Stress both in men and women can affect fertility. Stress can interfere with your hormones and affects normal ovulation. And if you don't ovulate then you won't get a regular menstrual period. So if you don't ovulate regularly, one of the causes could be stress. In men, stress can have a negative effect on fertility too. 

Chemicals and metals

Because the development of the fetus is a critical window of human development, any toxic exposure during pregnancy, and even before pregnancy can have effects.

We are all exposed to chemicals and metals in the environment including:

• Air
• Water
• Soil
• Food
• Consumer products

An analysis of the National Health and Nutrition Examination Survey data from 2003–2004 found that virtually every pregnant woman in the United States is exposed to at least 43 different chemicals. Chemicals in pregnant women can cross the placenta, and in some cases, such as with methyl mercury, can accumulate in the fetus, resulting in higher fetal exposure than maternal exposure.

There’s no avoiding the chemical stew in the environment today and some of these chemicals can affect reproductive health in women and men. This effect on the health of mothers, fathers, and babies in utero has prompted the American Congress of Obstetricians and Gynecologists (ACOG) to call for stricter policies concerning environmental chemicals, identification of the riskiest chemicals and the levels at which they become dangerous, and ways to reduce exposure to them.

In response, the American Chemistry Council (ACC) says enough is being done. That the fine line between awareness and alarmist might cause undue distress and distraction from traditional means of working toward optimum health during pregnancy.

The ACOG, as well as the American Society for Reproductive Medicine, say there isn’t enough concrete evidence that the exposure to the chemicals in everyday living is safe and there are few if any, studies that establish safe levels of exposure. They’re calling for the discussion of routine exposure to environmental chemicals to be a standard part of every prenatal visit. They’d also like to see a further scientific study that identifies risks and establishes safe levels of exposure.

Almost every American of every age has traces of BPA in his or her urine.

Socioeconomic differences mean some mothers are exposed to more dangerous chemicals than others and at levels more dangerous than in the general population. The workplace is often the source of exposure to some of the most dangerous chemicals an expectant mother faces and the AOCG suggests a discussion of these on-the-job risks might prevent a significant amount of birth defects, miscarriage, and other problems associated with infertility.

Hair coloring and women

A recent 2019 study showed that chemicals in hair products could increase the risk of breast cancer. Chances are that it's safe to color your hair in pregnancy. But there is no simple answer to this question, and the truth is we can't be 100% sure it's safe.

Air pollution and fertility

Research suggests that air pollution is particularly detrimental to the developing baby during pregnancy. In fact, researchers have detected negative effects in both mother and fetus from air pollution levels below the current U.S. Environmental Protection Agency (EPA) standards. A large-scale study revealed that, in a single year, air pollution was the cause of 16,000 premature births in the U.S. alone. 

Endocrine-disrupting chemicals (EDC)

Endocrine-disrupting chemicals (EDC) are synthetic chemicals that when absorbed into the body either mimics or blocks hormones and disrupt the body's normal functions.

This disruption can happen through altering normal hormone levels, halting or stimulating the production of hormones, or changing the way hormones travel through the body, thus affecting the functions that these hormones control.

Cadmium and pregnancy

Few people have heard about a chemical called Cadmium which is a metal present in the air, soil, water, and food. According to the CDC, "..when released into the atmosphere by smelting or mining or some other processes, cadmium compounds can be associated with respirable-sized airborne particles and can be carried long distances. It is deposited onto the earth below by rain or falling out of the air. Once on the ground, cadmium moves easily through soil layers and is taken up into the food chain by uptake by plants such as leafy vegetables, root crops, cereals, and grains." Increased cadmium levels in pregnant women can lead to many adverse pregnancy outcomes such as low birthweights, preterm births, small for gestational age babies. Reducing cadmium levels can lead to improved pregnancy outcomes.

Plastic food and beverage packaging

Almost all packaged foods and beverages contain BPA in the package materials, be it a can, box, bag, or plastic container of any kind. BPA can lead to significant negative effects on fertility and pregnancy. Bisphenol-A (BPA) is still being used in the canned food industry even after the chemical has been banned in the production of baby bottles and sippy cups. Many nations have banned the use of BPA for all reasons in all products but the U.S. still allows it in plastics intended for use by adults and older children and to line canned foods. Almost every American of every age has traces of BPA in his or her urine.

Common household chemicals: The dirty dozen

Some chemicals commonly used in the home, workplace, and just about everywhere else are known as endocrine disrupters because once ingested, they mimic the activity of the body’s natural hormones. In your home, there are known chemicals that can affect your fertility and pregnancy. Pesticides are found in many foods, and there is a so-called "dirty dozen" of produce that should be observed for increased pesticides.

Air pollution and pregnancy 

There are several studies showing that polluted air can lead to adverse pregnancy outcomes including congenital malformations of the fetus, higher risk for preterm birth, and decreased weight gain during pregnancy.

Water pollution and pregnancy

Outside the workplace, every woman is exposed to chemicals in the food supply that can affect the health of a fetus. Mercury in the food supply, for example, might be minimized when a woman knows which fish are more likely to be polluted by this heavy metal which can impair brain development in the child she carries.

Since exposure to these common environmental chemicals can hardly be avoided, the AOCG advocates awareness and education that should begin at the earliest stage of pregnancy if not before.