Thanks to the worldwide campaign, providing the informative, sociological, and psychological pressure on the smokers, the health risks of tobacco smoking are well known even to the involved population with regard to diseases of the heart, lungs, and blood vessels. Substantial harmful effects of cigarette smoke on fertility have been in a focus of multiple studies, and they are overwhelmingly confirmed by independent statistical and medical results. However, not all the smokers, especially from the younger generations, accept this medical conclusion. Unfortunately, the fact that cigarette smoking has a negative impact on the ability to become pregnant and carry a pregnancy to term for woman has been established, and if you decide to keep smoking while you plan to have a child in the nearest future, be aware on the possible negative consequences.
Note that Infertility statistics in society have established that about among women between the ages of fifteen and forty four, close to 12 percent suffer from some form of infertility. This percentage roughly measures up to about seven and a half million. Essentially, there are two things that are taken into consideration here – problems with getting pregnant and problems during pregnancy.
Impact of cigarette smoking on reproduction in women
Virtually all scientific studies support the conclusion that cigarette smoking has an adverse impact on fertility. The prevalence of infertility is higher, and the time it takes to conceive is longer for smokers, compared to nonsmokers. Active smoking by either partner has adverse effects, and the impact of passive cigarette smoke exposure may also be noticeable while reviewing the whole picture.
Research indicates that cigarette smoking is harmful to a woman’s ovaries, and the degree of harm is dependent upon the amount and the period of time a woman smokes. Smoking appears to accelerate the loss of eggs and reproductive function and may advance the time of menopause by several years. Components in cigarette smoke have been shown to interfere with the ability of cells in the ovary to make estrogen and to cause a woman’s eggs (oocytes) to be more prone to genetic abnormalities.
For example, one of the studies done in mice showed that nicotine had disruptive effects on egg maturation, ovulation rates, and fertilization rates. The study also showed more chromosomal abnormalities in the eggs exposed to nicotine.
Another study offered the following statistical data: 38% of female non-smokers conceived in their 1st cycle of attempting pregnancy compared to 28% of smokers. Smokers were also 3-4 times more likely than non-smokers to have taken greater than a year to conceive.
As was already mentioned before, more cigarettes a woman smokes a day, the longer she may take to get pregnant. According to one study, which looked at just over 4,000 women, after three and a half months of trying to get pregnant, almost 60% of non-smokers had achieved pregnancy. For women who smoked one to ten cigarettes a day, around 50% had achieved pregnancy. And for women who smoked over ten cigarettes per day, only 45% had achieved pregnancy after three and a half months. If quitting completely does not seem to be in the cards for you, cutting back is still worth trying for.
Smoking is also strongly associated with an increased risk of spontaneous miscarriage and possibly ectopic pregnancy. Pregnant smokers are more likely to have low birth weight babies and premature birth. The incidence of sudden infant death syndrome (SIDS) also slightly increases in households where someone smokes.
Impact of cigarette smoking on assisted reproductive therapy outcomes
Nearly twice as many in vitro fertilization (IVF) attempts are required to conceive in smokers than in nonsmokers. Studies of IVF have reported that female smokers require higher doses of gonadotropins to stimulate their ovaries, have lower peak estradiol levels, fewer oocytes obtained, more canceled cycles, lower implantation rates, and undergo more cycles with failed fertilization than nonsmokers.
One study showed that the chance for an IVF pregnancy was 2.7 times higher for women who have never smoked as compared to women that do (or have previously). The same study showed that if the woman smoked for over 5 years, the risk was increased to 4.8.
Miscarriage rates are also increased. The adverse effect of cigarette smoking is more noticeable in older women. Overall, the reduction in natural fertility associated with smoking may not be overcome by assisted reproductive technologies.
Impact of cigarette smoking on reproduction in men
Men who smoke cigarettes have a lower sperm count and motility and increased abnormalities in sperm shape and function. The reason for the sperm count and quality decrease is based on a fact that tobacco smoking may affect the testosterone levels.
Another risk factor for fertility in men is related to the fact that smoking can gradually and permanently damage all blood vessels, including those that carry blood to the penis. This can make it difficult to get or maintain an erection.
The effect of smoking on male fertility in general, however, is more difficult to discern because it is difficult to create studies to address that question. Although the effects of cigarette smoking on male fertility remain inconclusive, the harmful effect of passive smoke on the fertility of female partners and the evidence that smoking adversely affects sperm quality suggest that smoking in men should be regarded as an infertility risk factor.
In the recent study, performed by Dr. Lani Burkman, a fertility expert at the University of Buffalo School of Medicine, it has been compared sperm samples from 18 smokers to a similar group of men who never smoked. As part of the test, researchers divided the protective layer that covers female eggs in half and placed them in a separate lab dish. The smoker's sperm samples were tested against one half of the egg covering, while the non-smokers were tested against the other half. Success was judged by the ability of the sperm to stick to this outer coating. Result showed that the men who smoked 18 or more cigarettes a day for at least two years had about one quarter of the fertilization power as non-smokers. Those who smoked less had better functioning sperm, suggesting that guys may not have to go cold turkey to improve their chances. "If we can get men to cut down to five or six cigarettes a day, they can increase their fertility," suggested Dr. Burkman.
Smoking cessation as a treatment issue in couples undergoing fertility therapy
One important investigation showed that cessation of smoking for at least two months before attempting IVF signiﬁcantly improved chances for conception. Although long-term cigarette smoking can have an irreversible effect on ovarian function, the harmful effect on treatment outcome may, in part, be reversed if smoking is discontinued prior to entering into fertility therapy.
The best available scientiﬁc data indicate that cigarette smoking strongly contributes to infertility. So if you have been planning a child, then it is about time to give up on smoking. This is a very important stage in your lives, and you should show the best love and support to yourself and your partner. Quitting smoking, at least temporary, will definitely help to prevent very unpleasant possible consequences.
Smoking should be especially discouraged for both male and female partners in couples with a history of infertility or recurrent miscarriage. Smoking cessation may improve natural fertility and success rates with infertility treatment.
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