Maternal age and reproductive function in female Sprague-Dawley rats

Abstract

-We investigated the age-related changes in reproductive function in female rats of the Crl:CD(SD) strain. The estrous cycles were monitored from 6 to 42 weeks of age. Other females were mated with males at 6, 8, 10, 15, 19, 23, 27, 31, 35 and 40 weeks of age and caesarean section was performed on day 20 of gestation to examine their fetuses, and then reproductive parameters were calculated and fetal growth was observed. The percentage of rats exhibiting irregular estrous cycles increased from 23 weeks of age. The copulatory and fertility indices decreased from 35 and 27 weeks of age, respectively. Dams at 6 weeks of age showed low numbers of corpora lutea and implantation sites. Although the number of corpora lutea was not affected by advanced maternal age, number of implantation sites decreased from 27 weeks of age. The pre-and post-implantation loss rates increased from 23 and 31 weeks of age, respectively, and the number of live fetuses decreased from 27 weeks of age. Fetal growth retardation was observed in maternal rats older than 31 weeks of age. The external observations on the fetuses revealed umbilical hernia at 35 to 40 weeks of age. These data indicated that maternal aging affected reproductive function and fetal development from 23 and 31 weeks of age, respectively. It was considered that the appropriate age of Crl:CD(SD) female rats for the assessment of reproductive toxicity were 8 to 22 weeks.

Magzati és anyai betegségek kockázata 40 évesnél idősebb édesanyák esetén

“…Ma már számos közlemény [8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50] : 1,32). A császármetszés gyakorisága először szülőknél és többedszer szülőknél egyaránt lényegesen magasabb a 30 éves korosztályhoz képest.…”

Association between Female Reproductive Health and Mancozeb: Systematic Review of Experimental Models

“…To this aim, Cuomo et al suggested that ethylene thiourea exposure in mouse models leads to a remarkable dysregulation of ovarian aging biomarkers, affecting ovarian health [46]. Environmental exposure to ETU, in fact, induces alterations in the estrous cycle, considered the beginning of an early reproductive senescence [37,39,40,46,50]. In addition, Atmaca et al found that mancozeb induces a progressive decline in steroid synthesis in bovine luteal cells [35].…”

Human umbilical cord mesenchymal stem cells improve the reserve function of perimenopausal ovary via a paracrine mechanism

“…Vaginal smears of rats were taken to determine estrous cycle at 11:00 am daily. Only aging rats with disorganized estrous cycles and young rats with normal estrous cycles were chosen [27, 28]. Before the experiment, 1 ml of blood was gathered from each rat’s orbital during dioestrus.…”