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Risk scores for predicting small for gestational age infants in Japan: The TMM birthree cohort study
Noriyuki Iwama1,2, Taku Obara3,4,5, Mami Ishikuro3,4
1Department of Obstetrics and Gynecology, Tohoku University Hospital, 1-1, Seiryomachi, Sendai, Miyagi, 980-8574, Japan. noriyuki.iwama@med.tohoku.ac.jp.
Insights
This study developed a pregnancy risk score to predict small-for-gestational-age (SGA) infants in Japan. Mid-gestation risk scores showed acceptable predictive ability for SGA, outperforming early-gestation scores.
Area of Science:
- Obstetrics and Gynecology
- Perinatal Medicine
- Public Health
Background:
- Small-for-gestational-age (SGA) infants face increased risks.
- Accurate prediction models are crucial for timely interventions.
- Existing prediction tools may lack precision in specific populations.
Purpose of the Study:
- To develop and validate a risk score for predicting SGA infants in Japan.
- To compare the predictive performance of early versus mid-gestation risk scores.
- To identify key predictive factors for SGA during pregnancy.
Main Methods:
- A prospective cohort study of 17,073 subjects (Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study).
- Multiple logistic regression was used to construct risk scores at early (11-17 weeks) and mid-gestation (18-21 weeks).
- Risk scores included maternal demographics, lifestyle factors, medical history, and fetal measurements.
Main Results:
- The mid-gestation risk score achieved a C-statistic of 0.725 (95% CI: 0.710-0.740).
- The early-gestation risk score achieved a C-statistic of 0.658 (95% CI: 0.642-0.675).
- Mid-gestation scores demonstrated superior predictive ability for SGA compared to early-gestation scores.
Conclusions:
- Risk scores developed during mid-gestation provide acceptable prediction for SGA infants.
- Predictive performance is significantly better in mid-gestation than in early gestation.
- These findings can aid in early identification and management of SGA pregnancies.
Abstract:
This study aimed to construct a prediction model for small-for-gestational-age (SGA) infants in Japan by creating a risk score during pregnancy. A total of 17,073 subjects were included in the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study, a prospective cohort study. A multiple logistic regression model was used to construct risk scores during early and mid-gestational periods (11-17 and 18-21 weeks of gestation, respectively). The risk score during early gestation comprised the maternal age, height, body mass index (BMI) during early gestation, parity, assisted reproductive technology (ART) with frozen-thawed embryo transfer (FET), smoking status, blood pressure (BP) during early gestation, and maternal birth weight. The risk score during mid-gestation also consisted of the maternal age, height, BMI during mid-gestation, weight gain, parity, ART with FET, smoking status, BP level during mid-gestation, maternal birth weight, and estimated fetal weight during mid-gestation. The C-statistics of the risk scores during early- and mid-gestation were 0.658 (95% confidence interval [CI]: 0.642-0.675) and 0.725 (95% CI: 0.710-0.740), respectively. In conclusion, the predictive ability of the risk scores during mid-gestation for SGA infants was acceptable and better than that of the risk score during early gestation.
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