Objective

To investigate whether the reduced reproductive rate among men born small for gestational age (SGA) or with low birth weight (LBW) is present after up to 44 years of follow-up.

Design

Population-based register study.

Setting

National registers in Sweden.

Patient(s)

All men born in Sweden between 1973 and 1993 (n = 1,045,167) followed up to 2018.

Intervention(s)

None.

Main Outcome Measure(s)

Registered fatherhood, infertility diagnoses, and fertility treatments obtained from registers up to 2018

Result(s)

Men born SGA or with LBW have a lower chance of becoming fathers than men born with normal birth characteristics: hazard ratio (95% confidence interval) 0.91 (0.90–0.92) and 0.88 (0.86–0.90), respectively. The reduction in reproductive rate is more evident after a longer follow-up time. Men born SGA were more likely to receive a diagnosis of infertility. Sperm donation and intracytoplasmic sperm injection were more often used in men born SGA, further strengthening the hypothesis of an association between birth characteristics and male infertility.

Conclusion(s)

Men born SGA or with LBW have a lower chance of becoming fathers, but the reduction in fertility is smaller for the younger cohort. Further studies are needed to determine if this difference is maintained.

中文翻译：

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出生时小于胎龄或出生体重低的男性不会随着时间的推移而提高其生育率：一项基于瑞典人群的研究

客观的

调查在长达 44 年的随访后，出生时小于胎龄 (SGA) 或低出生体重 (LBW) 的男性的生育率是否降低。

设计

基于人口的登记研究。

环境

瑞典的国家登记册。

耐心）

1973 年至 1993 年间在瑞典出生的所有男性 (n = 1,045,167) 随访至 2018 年。

干预措施

没有任何。

主要观察指标）

截至 2018 年从登记处获得的注册父亲身份、不孕症诊断和生育治疗

结果）

SGA 或 LBW 出生的男性成为父亲的机会低于出生特征正常的男性：风险比（95% 置信区间）分别为 0.91（0.90-0.92）和 0.88（0.86-0.90）。在较长的随访时间后，生殖率的降低更为明显。出生 SGA 的男性更有可能被诊断为不孕症。精子捐赠和胞浆内精子注射更常用于出生 SGA 的男性，进一步加强了出生特征与男性不育之间关联的假设。

结论

出生 SGA 或 LBW 的男性成为父亲的机会较低，但年轻一代的生育率下降幅度较小。需要进一步的研究来确定是否保持这种差异。