**2. Effect of tobacco on female infertility and reproductive health**

### **2.1 Smoking and conception delay**

Smoking women experience almost 50% conception delay for over 1 year than nonsmokers women. Besides, active and/or passive tobacco smoking by either partner had adverse effects on conception [97].

Smoking couples, with a conception of over 15 cigarettes daily, demonstrated low fecundity and an increased time to achieve pregnancy [98].

The majority of studies support the negative effects of smoking on fecundity, regardless of other factors [98, 99].

Several reviews have accumulated data on female fecundity and cigarette smoking. All of them concluded that smoking adversely affects female fertility [100].

### **2.2 Smoking and ovarian function**

Compounds of tobacco smoke seem to accelerate the loss of reproductive function and follicular depletion [101].

Women who were exposed to tobacco during the fetal period showed an increase in ovarian dysgenesis [102]. A relation was found between smoking and short menstrual cycle length, that could lead to low fecundity [103]. Moreover, smoking women have their menopause 1–4 years in comparison to nonsmokers women [104].

Women consuming tobacco have high levels of nicotine, which can induce ovarian dysgenesis, resulting in increased infertility [102, 105]. On the other hand, other chemicals in cigarettes can affect the anatomy and function of the uterine tubes [106]. Another study reported that tobacco exposure during pregnancy can cause longlasting effects in the reproductive system [52].

### **2.3 Smoking and early pregnancy loss**

Tobacco smoke showed an association with bacterial vaginosis, which in turn is associated with second-trimester miscarriage and with preterm labor [107].

A case–control study demonstrated that smoking women (>20 cigarettes/day) had an increased risk of ectopic pregnancy in comparison to nonsmokers women [108]. An increase in spontaneous miscarriage is associated with tobacco smoke in both natural and ART cycles [109].

Moreover, 24% of women with experience of abortion and 19% of women without experience of abortion were passives smokers [110]. Passive smoker women *Smoking and Its Consequences on Male and Female Reproductive Health DOI: http://dx.doi.org/10.5772/intechopen.104941*

had low fertility rate and a risk of abortion four times higher in comparison to nonsmokers [111].

A dose–response relationship has been found between miscarriage and smoking. One percent increase in relative risk of miscarriage per cigarette smoked daily. Besides, the risk of miscarriage increased by 11% among pregnant women exposed to secondhand smoke [112].

Pineles et al. demonstrated also that the amount of cigarette smoked by the pregnant woman increases the risks of stillbirth, neonatal death, and perinatal death [112].

In a large cohort study, parental smoking during pregnancy was found to increase the risk of stillbirth, and paternal smoking was an independent risk factor for stillbirth despite maternal passive smoking status [113].

#### **2.4 Female smoking and assisted reproductive treatment (ART)**

A smoking woman seems to have reduced fertility and difficulty in conceiving. Different studies showed that tobacco may affect hormone production, which makes it difficult for a woman to become pregnant [114].

Studies have also reported that smoking woman, during fertility treatment, had higher numbers of canceled cycles, lower peak estradiol levels, an elevated gonadotropin injection for ovarian stimulation, increased testosterone, fewer oocytes retrieved, thicker zona pellucida, and more cycles with failed fertilization and implantation compared with nonsmokers [92, 115, 116]. Besides, the success rates of IVF were lower in smoking woman compared with nonsmokers one [117].

Some have also shown that female smoking is associated with reduced numbers of oocytes [118], lower fertilization [115, 119] and pregnancy [119], and higher miscarriages rate [120]. In contrast, other studies have reported that smoking has no adverse effects on fertilization [3] and pregnancy outcomes [121].

Freour demonstrated that active smoking women presented poor ovarian response and lower clinical pregnancy rate [122]. Moreover, an association has been described between current smoking woman, undergoing IVF, and lower concentrations of anti-mullerian hormone (AMH) [122, 123]. In addition, AMH levels were 44% higher in nonsmokers compared with current smokers [124] and declined 21% faster yearly in smokers compared with nonsmokers [125].

Ozbakir and Tulay investigated the association between cigarette smoking and oocyte quality. They concluded that cigarette smoking did not affect the follicles count and the number of oocytes retrieved. However, a significant difference was detected in the morphological assessment of oocyte including cytoplasmic anomalies [126].
