ABSTRACT
ObjectiveTo investigate the risk factors of fertility behaviors with preterm birth and low birth weight， and to develop a nomogram model to predict the occurrence of low birth weight. MethodsBirth registration information in Shanghai from 2010 to 2020 was collected， and ANOVA and Chi-square tests were used to compare the differences in reproductive behavior factors and newborn health status across time. The odds ratio （OR） value and 95%CI were calculated by a multi-classification logistic regression model to determine the association between reproductive behavior factors and preterm birth or low birth weight infants. A nomogram model was established based on logistic model and the area under the ROC curve was used to assess the effect of the model. ResultsThis analysis included 2 089 384 live newborns. The incidence of full-term low birth weight， preterm normal weight and preterm low birth weight in Shanghai was 0.94%， 2.48% and 2.01%， respectively. From 2010 to 2020， 40.00% women had a history of abortion， the proportion of women who gave birth at age ≥40 years old increased from 1.05% to 2.24%， the proportion of fathers aged ≥40 years increased from 4.79% to 7.48%， and the proportion of women with postgraduate or above increased from 4.81% to 11.74%. The incidence of preterm low birth weight in Shanghai showed an increasing trend over time. Logistic regression analysis showed that the risk of preterm low birth weight was lower in female than in male infants （OR=0.97， 95%CI： 0.95‒0.98）， and the risk of full-term low birth weight was higher than in male infants （OR=1.85， 95%CI： 1.80‒1.90）. The risk of preterm birth and low birth weight was lower for couples of childbearing age with higher education. The risk of preterm low birth weight in newborns tended to increase with maternal age at childbirth >30 years， paternal age ≥40 years， and the number of abortions >2 times. Mother <25 or >35 years， father aged 30‒34 years， and the number of abortions >3 times were the risk factors of full-term low birth weight infants. ConclusionCouples of childbearing age who choose to have children at too high or too low age may increase the risk of preterm birth or low birth weight， so it is necessary to strengthen population awareness and promote age-appropriate childbirth. Multiple abortions are also associated with preterm birth and low birth weight， and it is advisable to popularize the scientific knowledge of contraception and birth control to reduce unnecessary abortions. The nomogram in the study can visualize the risk of full-term and low birth weight infant at different levels of factors， which can assist couples preparing for pregnancy in making decisions about the timing of childbirth and understanding the level of risk.
ABSTRACT
This study was conducted to investigate the effect of diets containing raw or fermented cottonseed cake on reproductive characteristics of rabbit bucks. Eighteen (18) weaned crossbred (New Zealand White X Chinchilla) rabbit bucks, 6-7 weeks old, were randomly allotted to three treatments with six animals per treatment in a Completely Randomized Designed experiment. The treatment diets were T1, (Control) containing soyabean meal (SBM) as the main protein source; T2, Raw Cottonseed Cake (RCSC) - based diet and T3, Fermented Cottonseed Cake (FCSC) - based diet. The fermentation was done by inoculation with Aspergillus niger. Animals were acclimatized for one week. The feeding trial lasted for 9 weeks. At the end of this trial, 3 bucks per treatment were slaughtered and the reproductive organs dissected out for testicular and epididymal morphometrics as well as gonadal sperm assessment. Testicular morphometrics were not significantly (P>0.05) affected by the treatment. Treatment had significant (P<0.05) effect on the epididymal weight and length of rabbit buck. Testicular sperm count for the RCSC group (124.67x106) was significantly (P<0.05) lower than that of the control (182.22x106). Bucks on FCSC diet had comparable sperm count (181.50x106) with the control group. The proportion of motile sperm was significantly (P<0.05) increased from 48% in the control to 66.33% in the FCSC group. It was concluded that raw CSC had adverse effect on the sperm characteristics of rabbit bucks. However fermentation, using Aspergillus niger mitigated the adverse effect of CSC on the sperm characteristics. It is recommended that CSC to be included in diet of rabbit bucks meant for breeding purpose should be fermented by Aspergillus niger.