Background
Methods
Data source and study design
Preconception risk evaluation and classification model
Category | Definition | Risk factors |
---|---|---|
A | Avoidable risks, i.e. they could be avoided though health education and eliminating work place hazards etc. | Maternal: smoking, alcohol consumption, exposure to toxins, radiation, noise, pesticide, organic solvent, heavy metal, inadequate nutrition (no intake of meat and egg, no intake of fresh vegetables, raw meat eating habit) Paternal: smoking, alcohol, consumption, exposure to toxins, radiation exposure, noise, pesticide, organic solvent, high temperature, preputial ring, inadequate nutrition (no intake of meat and egg, no intake of fresh vegetables, raw meat eating habit) |
B | Benefiting from targeted medical intervention, | Maternal: anemiaa, bacterial vaginitis, candida infection, gonorrhoea, trichomoniasis, Toxoplasma gondii infection (IgM positive), gingival hemorrhage, history of psychological disorder; Paternal: abnormal liver function, abnormal renal function, spermatic cord varicocele, hypertension, congenital heart disease, history of chronic renal disease history, cancer, epilepsy, or psychological disorder |
C | Controllable risk factors, i.e. diseases and conditions that can’t be cured but risk can be modified and ameliorated. Close monitoring and medical supervision is required during the pregnancy | Maternal: Thrombocytopeniab, abnormal liver function, abnormal renal function, abnormal TSH, HBs-Ag positive, HBe-Ag positive, cytomegalovirus IgM positive, chlamydia positive, syphilis screening positive, Rh negative, history of gynecological diseases, preterm birth, diabetes, congenital heart disease, hypertension, malignancy, chronic renal disease, reported epilepsy, tuberculosis, use of narcotics; Paternal: HBs antigen positive, HBe antigen positive, syphilis screening positive, use of narcotics, thyroid disease |
D | Diagnosable prenatally but risk factor is not modifiable preconceptionally i.e. women with these risk factors may benefit from preconception risk evaluation, counseling and prenatal diagnosis. | Maternal: Maternal birth defect, history of previous child with birth defects, mental retardation, history of recurrent abortion, stillbirth, or neonatal death, family history of Mediterranean anemia, G6PD deficiency, Albinism, Down’s syndrome, visual impairment; hearing impairment; Paternal: Paternal birth defect, mental retardation, family history of neonatal death, Mediterranean anemia, G6PD deficiency, Albinism, Down’s syndrome, hemophilia, family history of visual impairment or hearing impairment |
X | Women with these risk factors are advised against pregnancy. Pregnancy should be evaluated under specialist after treatment. | Maternal: severe heart failure, severe thrombocytopeniac, severe anemiad |
Statistical analysis
Results
General characteristics of the study population
No risk factors | A | B | C | D | X | ||
---|---|---|---|---|---|---|---|
Age | ≤25 | 24.7% | 21.6% | 26.3% | 22.4% | 14.7% | 21.3% |
25–30 | 46.3% | 47.4% | 46.7% | 44.1% | 38.5% | 46.0% | |
30–35 | 19.5% | 21.2% | 18.2% | 20.9% | 27.1%* | 20.1% | |
≥35 | 9.6% | 9.8% | 8.7% | 12.6% | 19.8%* | 12.6%* | |
Area | Rural area | 93.9% | 89.6% | 94.0% | 94.0% | 94.3% | 92.2% |
Race | Han | 92.7% | 91.6% | 92.5% | 88.7% | 84.0%* | 84.2%* |
Education | Secondary school or lower | 71.5% | 64.8%* | 69.4% | 71.8% | 77.4% | 75.5% |
High school | 18.7% | 19.7% | 18.7% | 17.1% | 13.8%* | 16.6% | |
College or higher | 9.8% | 15.5%* | 11.8% | 11.1% | 8.8% | 8.0% |
No risk factors | A | B | C | D | X | ||
---|---|---|---|---|---|---|---|
Age | ≤25 | 9.2% | 10.2% | 10.3% | 9.1% | 4.5%* | - |
25–30 | 43.1% | 44.5% | 44.9% | 45.5% | 38.6%* | - | |
30–35 | 28.8% | 27.6% | 28.0% | 28.1% | 33.0%* | - | |
≥35 | 18.9% | 17.6% | 16.8% | 17.3% | 23.9%* | - | |
Area | Rural area | 92.6% | 92.1% | 90.1% | 92.2% | 85.7% | - |
Race | Han | 92.7% | 91.3% | 88.4% | 92.3% | 91.1% | - |
Education | Secondary school or lower | 69.3% | 69.0% | 63.1% | 66.4% | 61.9% | - |
High school | 20.0% | 19.2% | 20.1% | 20.2% | 16.9% | - | |
College or higher | 10.6% | 11.8% | 16.8%* | 13.4% | 21.3%* | - |
Preconception risk factor classification
Distribution preconception risk factors
Risk factors | Total number (%) | Risk factors | Total number (%) |
---|---|---|---|
Maternal | Paternal | ||
A | |||
Alcohol consumption | 72,808(3.40%) | Alcohol consumption | 634,547(29.61%) |
No intake meat and egg | 29,126(1.36%) | Smoking | 622,834(29.07%) |
Noise exposure | 25,267(1.18%) | Preputial ring | 84,659(3.95%) |
Othersa | 82,739(3.86%) | Noise exposure | 48,399(2.26%) |
Pesticide exposure | 26,753(1.25%) | ||
No intake meat and egg | 25,857(1.21%) | ||
Organic solvent exposure | 24,211(1.13%) | ||
High temperature exposure | 23,388(1.09%) | ||
Othersi | 41,492(1.94%) | ||
B | |||
Anemiab | 179,941(8.40%) | Abnormal liver function | 152,862(7.13%) |
Gingival hemorrhage | 76,595(3.57%) | Abnormal renal function | 26,107(1.22%) |
Vaginitisc | 49,162(2.29%) | Othersj | 9,973(0.47%) |
Othersd | 12,257(0.57%) | ||
C | |||
Abnormal TSH | 135,958(6.34%) | HBs antigen positive | 135,958(5.87%) |
HBs-Ag positive | 101,970(4.76%) | HBe antigen positive | 101,970(1.68%) |
Gynecological diseases history | 73,107(3.41%) | Othersk | 10,111(0.47%) |
Abnormal renal function | 57,680(2.69%) | ||
Abnormal liver function | 54,192(2.53%) | ||
Thrombocytopeniab | 31,522(1.47%) | ||
HBe-Ag positive | 31,459(1.47%) | ||
Otherse | 132,582(6.19%) | ||
D | |||
Spontaneous abortion history | 57,060(2.66%) | Othersl | 4,305(0.20%) |
Adverse pregnancy historyf | 23,878(1.12%) | ||
Othersg | 8,873(0.41%) | ||
X | |||
Othersh | 5,259(0.25%) |