With the rapid changes in lifestyle, natural and social environment, the reproductive health status of couples in childbearing age continues to decline, and long-term outcomes of the rapidly increasing offspring conceived by assisted reproductive technology (ART) needs to be evaluated urgently. Therefore, the focus of research now needs to be extended from death and severe diseases to full life cycle and full disease spectrum.
In order to meet the demand for such research, we launched the Jiangsu Birth Cohort (JBC) study in April 2014, in three cities in Jiangsu (Nanjing, Suzhou, and Changzhou). It was a family-based prospective study consisting of both ART-conceived couples and natural-conceived couples. Long-term follow-up programs will be conducted for both spouses and their offspring. Data of couples and their offspring, such as environmental exposure, reproductive history, psychological and behavioral status, will be collected during follow-up. Peripheral blood, urine, umbilical blood, follicular fluid, semen were also collected at different follow-up nodes.
The overarching goals of the JBC were to systematically assess the health and wellbeing among children conceived using ART as compared to those who were conceived spontaneously, and to clarify whether the elevated risks are attributable to parental characteristics related to infertility or ART procedures taking into consideration of ART-related parental characteristics.Based on high-quality data and biological samples, JBC will play an extremely important supporting role and have a far-reaching impact on maternal and children's health care and reproductive health in China.
Object Recruitment
1. ART-conceived couples：
The JBC identified potential study participants among those who consulted ART treatment at ART clinics. Eligible participants were Chinese residents of the pre-specified cities and were going to receive in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) treatment. Those who planned to conceive by sperm donation, oocyte donation, or intrauterine insemination were excluded from recruitment. Upon identification, the couples were invited to participate in the JBC before their first egg retrieval cycle.
2. Natural-conceived couples：
The spontaneously conceived couples were invited and recruited from obstetrics departments when they established health record profiles during early pregnancy (8-14 weeks of gestation). Eligible couples were Chinese residents who planned to have routine antenatal clinical examinations in the same hospital.
Obstetricians or professional health workers explained the objectives, procedures, potential benefits and confidentialities of the study to all eligible families. Informed written consent was obtained from those who agreed to participate. The JBC provided each family a membership card and a unique family ID for further follow-up. The participants could withdraw from the cohort at any time. The study was approved by the ethics committees of Nanjing Medical University and the participating hospitals.
Research center
1. Nanjing Maternal and Child Health Care Hospital：
In July,2014, we launched the Birth Cohort Research Base in Nanjing Maternal and Child Health Hospitaly, a prospective and longitudinal study of a birth cohort consisting of both ART pregnancies and spontaneous pregnancies. This Research Base is the first pilot cohort of the study. 8 full-time staff were employed, responsible for research object recruitment, follow-up, information and sample collection, etc. Up to now, 3,300 ART families and 7,500 spontaneous conception families have been recruited.
2. Suzhou Municipal Hospital :
Jiangsu Birth Cohort Suzhou Municipal Hospital Research Base was officially launched in July, 2014.ART families andspontaneous conception families were recruited simultaneously. The research base is recruiting 9 full-time staff, responsible for research object recruitment, follow-up, information and sample collection, etc. Up to now, 3,900 ART families and 5,600 spontaneous conception families have been recruited.
3. Changzhou Maternal and Child Health Care Hospital：
Jiangsu Birth Cohort Changzhou Maternal and Child Health Care Hospital Research Base was officially launched in March, 2015.ART families and spontaneous conception families were recruited simultaneously.The research base is recruiting 5 full-time staff, responsible for research object recruitment, follow-up, information and sample collection, etc. Up to now, 1,500 ART families and 3,800 spontaneous conception families have been recruited.
