[An epidemiological investigation of perinatal teratomas in China].

Objective: To investigate the prevalence rate and epidemiological features of teratomas in China.

Methods: From 1987 through 1992, hospital-based cluster sampling method was adopted for collecting data. During that period all live or still births with 28 weeks of gestation or more were assessed within 7 days after delivery.

Results: 238 teratoma cases were identified in 4,489,692 births, including 198 isolated and 40 associated forms of teratomas. The prevalence rates of total teratomas, isolated and associated forms of teratomas were 0. 53/10000, 0.44/10000, 0.09/10000 respectively. The prevalence rates in urban areas and rural areas were 0.46/10000 and 0.66/10000, respectively. The prevalence rates of teratomas in male and female births were 0.80/10000 and 0.27/10000 correspondingly. The ratio of male to female teratomas was 1:2.76. The perinatal fatality rate of teratomas was 55.0%.

Conclusion: The most frequent teratomas were isolated forms. Time trends have not been found in the occurrence of teratomas. High prevalence in urban areas has been observed, compared to that in rural areas. The prevalence of teratomas in female births is three times as high as that in male births. In view of the high fatality rate, prenatal diagnosis and perinatal management of teratomas should be strengthened.