Background  The current research on microwave radiation and its reproductive damage is mainly focused on male, however, few studies have been done on women. The damage of microwave radiation to the female reproductive system is an important issue that needs to be solved urgently.

  Objective  To explore the short-term effects of microwave radiation exposure on the ovaries and functions of female mice.

  Methods  Totally 64 sexually mature female ICR mice were randomly divided into 4 groups according to the radiation intensity. The control group did not receive radiation (0 w/m²), while the frequency of the radiation group was 2 GHz, and three radiation gradients were set as 0.5 w/m² (low dose group), 1.5 w/m² (medium dose group), 2.5 w/m² (high dose group). After 14 days of continuous irradiation, 6 female mice in each group were randomly selected to collect blood from the eyeballs, and the serum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH) and estradiol (E₂) were measured by enzyme-linked immunosorbent assay (ELISA). The ovarian tissues were separated and weighted, and the ovarian index was calculated. One ovary was stained with hematoxylin-eosin (HE) to observe the morphological structure of the ovarian tissue, and the other ovary was subjected to chemical colorimetry to detect the oxidative stress level of the ovarian tissue. Another 10 mice in each group were caged with normal male mice. The pregnant mice were sacrificed after 18.5 days of pregnancy. The fetuses and placenta were weighed, and the pregnancy rate, litter size and sex of offspring were counted.

  Results  Compared with the control group, the levels of LH and FSH in the other three groups showed increasing trend without significant difference (P＞0.05), while the level of E₂ and ovarian index decreased significantly (P＜0.05, respectively). The ovarian structure of the exposed group showed varying degrees of damage, HE staining showed that the number of corpus luteum reduced, the granular cell layer became thin and disordered, and the number of granular cells and mature follicles reduced significantly, while the number of atretic follicles increased significantly. Compared with the control group, the contents of superoxide dismutase and catalase in ovarian tissue of female mice in the exposed group decreased significantly, while the level of malondialdehyde increased significantly in a dose-dependent manner (all P＜0.05). The uterine index and the expression levels of VEGF and VEGFR2 in uterine tissues were significantly lower in the mid- and high-dose exposed group than those in the control group (all P＜0.05). The pregnancy rate of high-dose group decreased significantly when compared with the control group (P＜0.05), and the litter size in the three exposed groups also decreased significantly, with the lowest showing in the high-dose group (P＜0.05). The proportion of male mice decreased significantly in the exposed groups (P＜0.05). Conclusion 2 GHz microwave radiation can cause a certain degree of damage to female mice's reproductive function, which is mainly reflected in the decrease of serum E₂ level, ovarian structure disorder, and reduction of uterine index and suppression of angiogenesis. The conception rate of female mice tends to decrease and the litter size of the offspring decreases significantly.