Morikawa Mamoru, Yamada Takashi, Yamada Takahiro, Cho Kazutoshi, Sato Shoji, Minakami Hisanori
Department of Obstetrics, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan.
J Obstet Gynaecol Res. 2014 Apr;40(4):926-31. doi: 10.1111/jog.12304. Epub 2014 Feb 26.
Whether prevalence rate of pregnancy-induced hypertension (PIH), including gestational hypertension and pre-eclampsia, is lower for summer delivery than for winter delivery remains to be studied in Japanese women.
The prevalence rate of PIH was retrospectively determined according to month of year at delivery and at conception in 301510 Japanese women who gave birth to singleton infants on or after gestational week 22 between 2005 and 2009.
The overall prevalence of PIH was 4.6% (13848/301510). The prevalence rate of PIH, ranging 3.6-4.6% for women with deliveries in July-August was consistently lowest during the 5-year study period. The mean ± standard deviation prevalence rate of 4.2 ± 0.3% for delivery in July-August was significantly lower than those for any other month (January-February, 4.7 ± 0.4%; March-April, 4.9 ± 0.4%; May-June, 4.6 ± 0.2%; September-October, 4.6 ± 0.1%; and November-December, 4.6 ± 0.2%). The prevalence rate of PIH was highest (4.9%) for women with conception in March and April and lowest (2.9%) for those with conception in November and December.
The prevalence rate of PIH was higher for delivery in winter and early spring and lowest for summer delivery among Japanese women.
在日本女性中，妊娠高血压（PIH，包括妊娠期高血压和子痫前期）的夏季分娩患病率是否低于冬季分娩患病率仍有待研究。
回顾性确定2005年至2009年期间在孕22周及以后分娩单胎婴儿的301510名日本女性的PIH患病率，根据分娩月份和受孕月份进行统计。
PIH的总体患病率为4.6%（13848/301510）。在为期5年的研究期间，7月至8月分娩的女性PIH患病率始终最低，为3.6%-4.6%。7月至8月分娩的平均±标准差患病率为4.2±0.3%，显著低于其他任何月份（1月至2月，4.7±0.4%；3月至4月，4.9±0.4%；5月至6月，4.6±0.2%；9月至10月，4.6±0.1%；11月至12月，4.6±0.2%）。3月和4月受孕的女性PIH患病率最高（4.9%），11月和12月受孕的女性患病率最低（2.9%）。
在日本女性中，PIH的患病率在冬季和早春分娩时较高，夏季分娩时最低。
