Assessment of Prior Infection With Hepatitis B Virus and Fecundability in Couples Planning Pregnancy.

IMPORTANCE: The association of hepatitis B virus (HBV) infection with reduced fecundability among reproductive-aged couples lacks large-population, in-depth study evidence. OBJECTIVE: To investigate the association of HBV infection with time to pregnancy in couples planning pregnancy, and to explore whether this association varied by gravidity, health statuses, or lifestyles. DESIGN, SETTING, AND PARTICIPANTS: This is a population-based cohort study of Chinese couples participating in the National Free Preconception Check-up Projects during 2015 to 2017. They were planning pregnancy and were followed-up every 3 months until getting pregnant, as confirmed by gynecologic ultrasonography, or were followed-up for 1 year. Data were analyzed between March 1, 2022, and September 30, 2022. MAIN OUTCOMES AND MEASURES: The main outcome was time to pregnancy, assessed using fecundability hazard ratios (HRs). The Cox proportional hazards regression models were used to estimate the association of HBV infection with fecundability. RESULTS: Among 2 419 848 couples (mean [SD] age, 27.87 [5.20] years for women and 29.58 [5.50] years for men), 126 728 women (5.24%) and 156 572 men (6.47%) were infected with HBV. Compared with the HBV-negative group, the fecundability of both women and men in the HBV-positive group decreased by 5% (HR, 0.95; 95% CI, 0.94-0.95). Compared with couples in which both partners were HBV negative, the fecundability of those in which both partners were HBV positive declined by 6% (HR, 0.94; 95% CI, 0.93-0.96) among all couples, by 3% (HR, 0.97; 95% CI, 0.95-0.99) among nulligravidas couples, and by 7% (HR, 0.93; 95% CI, 0.91-0.95) among multigravidas couples. Both the female-male and couple models suggested that the association of HBV infection with decreased fecundability was more pronounced in couples with multigravidas. The negative association was greater in people with overweight and obesity and was inconsistent in certain subgroups; in particular, it was more pronounced in women with reproductive tract infections, normal fasting plasma glucose, and no alcohol intake and in men with normal blood pressure. CONCLUSIONS AND RELEVANCE: In this population-based cohort study, HBV infection was associated with decreased fecundability in a general reproductive-aged population, especially in couples with multigravidas. For women and men with certain health statuses and lifestyles, a comprehensive consideration of this association is recommended to provide personalized fertility guidance.

Reference Range and Sociodemographic Characteristics of TSH among Reproductive Age Women in Rural China.

Appropriate reference range of thyroid-stimulating hormone (TSH) is important to interpreting the results of thyroid functional tests. However, the reference range and sociodemographic characteristics of TSH based on large-scale studies are yet to be declared in rural China. To clarify reference range and sociodemographic characteristics of TSH in reproductive age of women from rural China. A nationwide population-based study was conducted as The National Free Preconception Health Examination Project (NFPHEP). Nearly 400,000 (n = 392,659) of Chinese rural women aged 15-55 years were randomly recruited. Predetermined strict exclusion criteria made a number of 359,895 as the reference population. Serum TSH was evaluated with enzyme-linked immunosorbent assay (ELISA). The reference range of TSH on overall and reference population was 0.39-5.20 and 0.39-5.13 uIU/ml (2.5th-97.5th percentiles), respectively. In the reference population, the range (2.5th to 97.5th percentile) of serum TSH in different age groups was 0.40-5.03 uIU/ml, 0.39-5.15 uIU/ml, 0.37-6.10 uIU/ml, and 0.44-7.03 uIU/ml, respectively. The mean TSH value in women aged 26-35 years was 2.26 uIU/ml, significantly lower than those aged 36-45 (p < 0.001). The mean TSH values for eastern, central, and western regions were 2.28 uIU/ml, 2.29 uIU/ml, and 2.24 uIU/ml respectively. The mean of serum TSH concentration was significantly higher in central region than that in western region (p ≤ 0.001). The TSH value 0.39-5.13 uIU/ml (2.5th-97.5th percentiles) was derived as a reference range of reproductive age women from rural China. We use the TSH ranges from reference population to diagnose hyperthyrotropinemia or hypothyroidism in different areas in China. The reference ranges for eastern, central, and western regions were 0.33-5.61 uIU/ml, 0.40-5.04 uIU/ml, and 0.40-4.98 uIU/ml (2.5th-97.5th percentiles) respectively. The value of serum TSH was associated with age, living region, smoking, drinking, educational level, and interpersonal tension, as well as life and economic pressure, but irrelevant to ethnicity or occupation.

Socioeconomic inequality in periconceptional folic acid supplementation in China: a census of 0.9 million women in their first trimester of pregnancy.

BACKGROUND: To assess socioeconomic inequality in periconceptional folic acid supplementation in China. METHODS: We used data of periconceptional folic acid (FA) supplementation of rural Chinese women from the National Free Preconception Health Examination Project from 2010 to 2012 and socioeconomic level data from the National Bureau of Statistics. We used logistic models to assess the associations between the prevalence of taking FA and the sociodemographic characteristics of the participants, the couples, and the socioeconomic levels of their region of residence. RESULTS: Of the 907,720 included women, 682,315 (75.62%) of the women reported taking FA. The prevalence of FA supplementation was significantly higher in participants aged 21-29 (75.87%) than in those women aged 40-49 (68.44%, p < 0.01). The prevalence of FA supplementation was significantly higher in the region with the highest Per Capita Gross Regional Product than in the regions with lower Per Capita Gross Regional Product (aOR = 12.20 [95% CI:9.54-15.61]). The higher the per capita net income of farmer households in the region, the higher the prevalence of FA supplementation (aOR = 1.95 [95% CI:1.74-2.18]). CONCLUSIONS: The rate of periconceptional FA supplementation among rural Chinese women has increased with the support of China's Health System Reform policy. However, socioeconomic disparities in periconceptional folic acid supplementation remain.

Sociodemographic and economic characteristics of susceptibility to rubella among women preparing for pregnancy in rural China.

OBJECTIVES: Infection with rubella virus during pregnancy can result in congenital defects and adverse pregnancy outcomes. The risk of rubella infection is greatly determined by the level of rubella antibodies in the serum. A survey of rubella antibody seronegativity rates was conducted in 780 000 women in rural China who were planning a pregnancy, in order to evaluate the herd susceptibility in different age groups and by high, middle, and low GDP per capita regions. METHODS: In order to evaluate the herd susceptibility to rubella, a nationwide population-based study of rural Chinese women who were planning to have a baby and who were aged 21-49 years was instigated. As a part of the National Free Pre-conception Health Examination Project covering 29 provinces in 2012, a physical check-up program was provided to women who planned to become pregnant within the next 6 months. All medical data were from serological samples tested by ELISA, and the participants' immunity status was categorized based on levels of rubella antibodies. Economic data were also collected to explore the association between herd susceptibility and socioeconomic characteristics in the women of childbearing age. RESULTS: A total 264 306 of 782 293 recruited women preparing for pregnancy tested susceptible to rubella (33.79%). The seronegativity rate in women with a history of vaccination was significantly lower than that in women who had not received the vaccination or did not know their vaccination history (23.76%, 33.70%, and 35.68%, respectively). The seronegativity rates were 26.89%, 37.86%, and 32.61% in high, middle, and low GDP per capita areas, respectively. After stratified analysis and adjusting for other factors by multiple logistic regression, the lower seronegativity rates in women in high GDP per capita regions compared to women in middle and low GDP per capita regions remained in the different age groups and subgroups of immunization history. CONCLUSIONS: There is a clear difference in rubella-specific susceptibility among rural women preparing for pregnancy of different sociodemographic and economic backgrounds. The number of rubella-susceptible rural women preparing for pregnancy, especially in relatively low GDP per capita regions in China, was high. Offering rubella vaccination to women who are rubella-susceptible and who plan to become pregnant should become one of the priorities in the field of public health work in China.

China's community-based strategy of universal preconception care in rural areas at a population level using a novel risk classification system for stratifying couples´ preconception health status.

BACKGROUND: Preconception care (PCC) is recommended for optimizing a woman's health prior to pregnancy to minimize the risk of adverse pregnancy and birth outcomes. We aimed to evaluate the impact of strategy and a novel risk classification model of China´s "National Preconception Health Care Project" (NPHCP) in identifying risk factors and stratifying couples' preconception health status. METHODS: We performed a secondary analysis of data collected by NPHCP during April 2010 to December 2012 in 220 selected counties in China. All couples enrolled in the project accepted free preconception health examination, risk evaluation, health education and medical advice. Risk factors were categorized into five preconception risk classes based on their amenability to prevention and treatment: A-avoidable risk factors, B- benefiting from targeted medical intervention, C-controllable but requiring close monitoring and treatment during pregnancy, D-diagnosable prenatally but not modifiable preconceptionally, X-pregnancy not advisable. Information on each couple´s socio-demographic and health status was recorded and further analyzed. RESULTS: Among the 2,142,849 couples who were enrolled to this study, the majority (92.36%) were from rural areas with low education levels (89.2% women and 88.3% men had education below university level). A total of 1463266 (68.29%) couples had one or more preconception risk factors mainly of category A, B and C, among which 46.25% were women and 51.92% were men. Category A risk factors were more common among men compared with women (38.13% versus 11.24%; P = 0.000). CONCLUSIONS: This project provided new insights into preconception health of Chinese couples of reproductive age. More than half of the male partners planning to father a child, were exposed to risk factors during the preconception period, suggesting that an integrated approach to PCC including both women and men is justified. Stratification based on the new risk classification model demonstrated that a majority of the risk factors are avoidable, or preventable by medical intervention. Therefore, universal free PCC can be expected to improve pregnancy outcomes in rural China.

A new perspective on universal preconception care in China.

Many risk factors associated with adverse pregnancy outcomes can be identified and modified preconceptionally. Despite a broad consensus that preconception care should be provided to all couples of reproductive age, it has not been integrated in routine healthcare. There are several barriers to its implementation, and even in the most resourceful countries, it is only provided to some select high-risk groups, rather than being an organized healthcare service provision to all. Recently, China seems to be leading the way by implementing preconception care nationwide in all rural areas. Its National Free Preconception Health Examination Project is a unique model of comprehensive preconception care. Advantages of this ambitious project are now becoming evident and benefiting the most vulnerable sections of Chinese society. This commentary provides an overview of National Free Preconception Health Examination Project and highlights the concepts that could be further developed and adapted into a model of preconception care.

[Status assessment of preconception health risk exposure in Chinese reproductive women during 2010-2012].

OBJECTIVE: To assess the exposure status of preconception health risk of Chinese reproductive women and analyze the changes of their exposure status during 2010-2012. METHODS: The "Core Indicators of Preconception Health Risk Exposure Status in Chinese reproductive couples" were used to evaluate the preconception health risk of women during reproductive period (aged 21-49 years) who participated in National Free Preconception Health Examination Project. From January 1, 2010 to December 31 2012 a total of 2 120 131 women were recruited from 220 pilot counties of 31 provinces. The risks involved the following eight aspects: genetic risk, reproductive risk, chronic disease risk, infectious risk, nutritive risk, behavioral risk, environmental risk and psychosocial risk. RESULTS: The overall rate of preconception health risk in Chinese reproductive women (aged 21-49 years) was 54.63% (1 124 552/2 058 648). Among all age groups, the lowest rate was 53.05% (262 646/495 092) in 21-24 age group while the highest rate 66.94% (7616/11379) in 45-49 age group. The top three risks were nutritive risk [35.74% (726 826/2 033 730)], infectious risk [10.16% (206 983/2 037 022)] and chronic disease risk [6.96% (142 130/2 042 110)]. From 2010 to 2012, the rate of preconception health risk in Chinese reproductive women (aged 21-49) were 55.35% (182 087/328 991) (2010), 56.03% (502 888/897 511) (2011) and 52.82% (439 577/832 146) (2012) respectively. In different years, the rates of nutritive, infectious, behavioral and genetic risks were all highest in 2011. And the rates of eight types of risks were all lowest in 2012. In different age groups, all eight risks were lowest in 21-24 age group and highest in 45-49 age group. And the preconception health risk increased with age. CONCLUSION: The general status of preconception health of reproductive women is fair. However, there are still some risks. The preconception health risk in Chinese reproductive women showed a declining trend during 2010-2012.

[Status assessment of preconception health risk exposure among 2 030 083 males in 31 provinces during 2010-2012].

OBJECTIVE: To assess the exposure status of preconception health risk of Chinese males aged 21-49 years in 31 provinces and analyze the changes of their exposure status during 2010-2012. METHODS: The "Core Indicators of Preconception Health Risk Exposure Status in Chinese reproductive couples" were used to evaluate the preconception health risk of males aged 21-49 years who participated in National Free Preconception Health Examination Project. From January 1, 2010 to December 31, 2012, a total of 2 030 083 males were recruited from 220 pilot counties of 31 provinces. The risks involved three aspects closely correlated with offspring health: behavioral risk, infectious risk and genetic risk. RESULTS: The overall smoking rate of Chinese rural males aged 21-49 years was 31.19% (622 837/1 997 051). They smoked a daily average of 10 cigarettes. The median number of cigarettes smoked was 10 per day and it increased with age. The overall drinking rate was 31.81% (634 556/1 994 925). Meanwhile, median alcohol consumption increased with age. The rate of males with a history of birth defect, family inbreeding and familial genetic disease accounted for 0.12% (2 344/1 994 324), 0.20% (4 043/1 997 707) and 0.94% (18 736/2 000 005) respectively. The rates of males with a history of hepatitis B and sexually transmitted diseases were 0.67% (13 317/1 988 904) and 0.05% (912/1 988 904) respectively. HBsAg positive rate was 6.32% (124 274/1 965 821). And the positive screening rate of Treponema pallidum was 0.37% (7 169/1 947 021). Among three types of risks, the highest risk was behavioral risk while the lowest risk genetic risk. Behavioral risk, genetic risk and sexually transmitted diseases in infectious risk were all lowest in 2012 while HBV infection in infectious risk was lowest in 2010. CONCLUSION: The general status of preconception health is fair for rural males aged 21-49 years in 31 provinces. However, there are still some behavior, genetic and infectious risks. The preconception health risk of rural males showed an overall declining trend during 2010-2012.