A recent paper in the January issue of Fertility and Sterility continues to point to the negative effects of smoking, weight extremes, alcohol use, and stress on pregnancy rates in women who are attempting to conceive.
Smoking, both in increased frequency and duration can lead to a delay in conception of more than one year and is also known to decrease ovarian reserve in women.
Men who smoke have a 20% decrease in sperm count and motility. Stopping smoking for three months will allow a threefold increase in sperm count as well as motility.
Women under undergoing IVF have a greater than 40% reduction in success with IVF with moderate cigarette consumption.
Although not as well studies as cigarette smoking consuming cannabis several times a week also causes a reduction in volume and number of sperm
In women there is an increase of umenstrual cycle irregularity as well as a decrease number of eggs retrieved during in vitro fertilization.
In women, a small consumption of wine does not appear to decrease fertility. However, moderate-consumption of wine appears to reduce the time taken to conceive. Consumption of less than two glasses per day has not been found to have a negative effect on conception.
In men decreased fertility is generally only seen in men who consume three glasses of wine daily or it’s equivalent.
Less than 1.5 cups of coffee per day does not seem to have a major effect on fertility and either men or women. More on the effects of caffeine and pregnancy.
Weight extremes being overweight or underweight will decrease the chance of fertility. A BMI less than 20 (underweight)or BMI greater than 30 (overweight)have been shown to decrease fertility both naturally as well as with IVF.
Effects of stress are controversial and not clear at this time if menstruation is not affected.
Your lifestyle affects your fertility. All of these factors can accumulate to significantly decrease the pregnancy.
Fertility and Sterility, January 2015 (pages 22 to 26)