Prevalence of rear seat belt use among pregnant women in a suburban area of Japan.

AIM: The aim of this study was to clarify the prevalence and influencing factors of rear seat belt use among pregnant women. METHODS: Questionnaires were given to 1546 pregnant women who visited obstetrics clinics and hospitals for prenatal checkups from October to December 2013. A total of 1494 pregnant women (96.6%) agreed to participate in this study and completed the questionnaire. RESULTS: Fewer than 20% of the rear-seat passengers 'always' used seat belts before and during pregnancy, whereas a third 'never' used a seat belt before or during pregnancy. There was no significant decrease in seat belt use by rear-seat passengers during compared to before pregnancy. Multivariate analysis revealed that age, knowledge of how to use a seat belt during pregnancy, belief in the compulsory use of a rear seat belt and driver behavioral characteristics before pregnancy were associated with rear seat belt use during pregnancy. CONCLUSIONS: The prevalence of fastening seat belts was substantially low. The provision of information regarding proper seat belt use and its role in protecting the fetus may increase use.

In vitro fertilization embryo development from caffeine-treated murine sperm.

Purpose: To evaluate the effect of long-term caffeine administration on murine sperm and subsequent in vitro fertilization (IVF). Methods: Male mice were injected with various doses (0, 0.2 and 1.0 mg/mouse/day) of caffeine for 1 month. After sperm collection, the IVF rate and embryo development to the blastocyst stage were evaluated. Results: The mean body weight significantly decreased in the 1.0 mg/day treatment group compared to the control group (P < 0.01). Testicular weight and histological features did not differ, and total blood testosterone was no different in spite of the difference between 0.2 and 1.0 mg/day of caffeine. The IVF rate differed significantly between the control group [100/105 (95.2 %)] and 0.2 mg/day group [106/121 (87.6 %)] (P < 0.05). Furthermore, blastocyst formation was significantly and dose-dependently lower with higher caffeine levels: control group: 85/100 (85.0 %); 0.2 mg/day group: 84/106 (79.2 %) (P < 0.05); 1.0 mg/day group: 64/102 (62.7 %) (P < 0.001). Conclusions: Caffeine treatment affected body weight of male mice. However, testicular weight, histological features and total blood testosterone concentration were not statistically different. In addition, following IVF using sperm from these mice, blastocyst formation decreased in a dose-dependent manner. These findings suggest that embryo development from oocytes fertilized with sperm from caffeine-administered male mice is negatively affected.

Effect of long-term caffeine administration to mice on in vitro fertilization and embryo development using oocytes.

PURPOSE: To evaluate the effect of long-term caffeine administration to mice on in vitro fertilization (IVF) of oocytes. METHODS: Mice were injected with different dosages (0, 0.1, and 1.0 mg/mouse/converted day) of caffeine for one month. Subsequently, the fertilization rate and embryo development to blastocyst stage were evaluated in IVF using oocytes from the mice. RESULTS: The retrieved average oocyte rate was significantly lower (27.4) in mice injected with 1.0 mg caffeine than in the control group (36.5; P < 0.05); the fertilization rate was significantly different between the 0 mg (317/401; 79.1 %) and 1.0 mg group (199/301; 66.1 %) (P < 0.05). At 96 h after insemination, the blastocyst formation rate was significantly decreased in the 1.0 mg group (94/199; 47.2 %) compared with the control (0 mg) group (237/317; 74.8 %) and 0.1 mg group (226/323; 70 %) (P < 0.05). When 1.0 mg caffeine was administered for two weeks, embryo development was significantly impacted. CONCLUSIONS: Our findings suggest that caffeine administration negatively impacts oocytogenesis and embryonic development after IVF.

Ovarian follicular differentiation with prepubertal gonadotropin surges and gonadotropin priming in mice.

Preantral follicles were mechanically isolated from the ovaries of 1.5 to 8 week old mice and cultured in vitro for 4 days in the presence or absence of either activin A or FSH. Plasma gonadotropin, estradiol and immunoreactive (IR) inhibin levels were measured. Cultured follicles showed stepwise changes in response to recombinant human (rh) FSH, with no response until 11 days, a gradual increase from 2 weeks, culminating in a strong response to rhFSH at 8 weeks. The response to activin A was vice versa. It enhanced the effect of rhFSH on preantral follicular growth of up to 4-week-old mice, but inhibited the effect of rhFSH in 8-week-old mice. The peak of the prepubertal gonadotropin surge was observed on day 11. Seven-day-old mice were treated with either luteinizing hormone releasing hormone (LHRH) or rhFSH or human chorionic gonadotropin (hCG) for 3 consecutive days from day 7, and follicles were collected on day 11. Those follicles showed enhanced response to rhFSH, no response to activin A, and an enhanced response to the combination of rhFSH and activin A, suggesting that the chronological changes in follicular response are a result of the prepubertal gonadotropin surge.

Enhancing the fertility of poor responders by treatment with estrogen rebound combined with a short protocol.

Aim: To assess the efficacy of estrogen rebound (ER) plus flare-up by gonadotropin releasing hormone agonist (GnRH-a) in poor responders who failed to become pregnant prior to a long protocol treatment. Methods: The patients comprised of thirty-one infertile patients with oocyte retrieval levels of less than five, who had undergone several long protocol treatment cycles. The efficacy of treatment with the ER plus flare-up from GnRH-a was compared with the prior long protocol treatment. The main outcome measures are: confirmation of ER, maximal serum E2 levels prior to human chorionic gonadotropin (hCG) administration, follicular development, dose, and duration of gonadotrophins in a clinical setting. Results: The ER was confirmed by estrogen levels; FSH increased with ER plus flare-up from GnRH-a. Although the 31 patients included in the study had undergone frequent prior treatment cycles, including the long protocol, the pregnancy rate per embryo transfer following ER plus flare-up by GnRH-a was 37.5% (nine of 24). The number of follicles, number of oocytes retrieved, and the E2 level was higher than those found in prior treatment cycles. Conclusion: Exogenous estrogen administration with PremarinR plus flare-up by GnRH-a may represent an alternative and effective protocol for poor responder patients who had previously undergone several prior long protocol treatments. (Reprod Med Biol 2003; 2: 127-131).

Relationship between follicular fluid hormone levels, embryo quality, and maternal age during in vitro fertilization after the short or long protocol with a gonadotropin releasing hormone agonist.

Purpose: To examine the relationship between embryo quality and follicular fluid hormonal level in short and long protocol gonadotrophin releasing hormone agonist treatment cycles. Methods: A total of 90 patients had non-polycystic ovary syndrome (non-PCOS) and 10 had PCOS. A total of 100 subjects underwent in vitro fertilization (IVF). Thirty-six subjects underwent conventional IVF and 64 subjects underwent intracytoplasmic sperm injection (ICSI). The dominant follicles were initially retrieved and a hormonal assay was done. A total of 32 patients underwent a short protocol and 66 patients were treated with the long protocol. Estradiol (E2), progesterone (P4), total testosterone (TTE) and androstenedione (ASG) levels in follicular fluid (FF) were compared in the two treatment groups (short and long protocol), in regard to maternal age and oocyte/embryo quality. Results: The retrieval FF volume was not significantly different between the PCOS and non-PCOS patients; however, P4 was significantly lower with PCOS (P < 0.01). Analysis of four different hormone levels was not significantly different between the short and long protocol groups. No significant relationship was found between four hormone levels in regard to oocyte morphology and embryo quality. The levels of P4 of younger women was significantly lower than that of older women; furthermore, a significantly higher TTE and ASG were found in the younger women. Progesterone was found to statistically significantly increase with FF volume. Conclusion: Follicular fluid P4 from the younger group was significantly lower, and TTE and ASG was significantly higher when compared to the older group. Analysis of four different hormone levels revealed no significant difference between the short and long protocol groups. No significant relationship was found between four hormone levels, oocyte morphology, and embryo quality. (Reprod Med Biol 2003; 2: 165-169).