Warp Mari Landås, Grindstad Thea, Skåra Karoline H, Magnus Maria C, Håberg Siri E, Morken Nils-Halvdan, Romundstad Liv Bente, Ramlau-Hansen Cecilia H, Hanevik Hans Ivar
Telemark Hospital Trust, Fertilitetsavdelingen Sør, Porsgrunn, Norway.
Centre for Fertility and Health, Norwegian Institute of Public Health, Oslo, Norway.
Acta Obstet Gynecol Scand. 2025 Jun;104(6):1101-1111. doi: 10.1111/aogs.15088. Epub 2025 Apr 8.
Women's reproductive lifespan has increased over the past two decades. Simultaneously, female reproductive behavior has changed, with increasing age at first birth. Early menarche has been associated with adverse health outcomes, but research investigating the association between maternal age at childbirth and daughter's age at menarche is, so far, inconclusive. Whether the interval between menarche and childbirth or between childbirth and menopause among mothers is associated with age at menarche in daughters is not known.
We conducted a cohort study with retrospectively collected data including mothers and daughters participating in the Norwegian Mother, Father and Child Cohort Study. Within this cohort, we identified two study populations. First, we included 14 576 mother-daughter pairs with complete information on maternal age at menarche and childbirth and the daughter's age at menarche. Second, we included 1350 mother-daughter pairs with complete information on maternal age at childbirth and natural menopause, and daughter's age at menarche. We calculated odds ratios (OR) with 95% confidence intervals (CIs) in a discrete survival analysis for daughters' age at menarche by time intervals from menarche to childbirth or from childbirth to menopause in mothers. We adjusted for relevant covariates.
We found 5% lower yearly odds (partially adjusted OR 0.95 (CI 0.90-0.99)) of reaching menarche among daughters born by mothers <16 years after menarche compared to the reference category born 16-20 years following menarche. After additionally adjusting for maternal birth year, the effect estimate was further reduced (fully adjusted OR 0.79 (CI 0.74-0.84)). Among daughters born by mothers >20 years after menarche, the likelihood of early menarche was higher (fully adjusted OR 1.19 (CI 1.13-1.27)) compared to the reference category. Regarding the childbirth-menopause interval, our findings did not reach statistical significance in either of our models.
Daughters born to mothers with a shorter time interval (<16 years) between menarche and childbirth have a lower likelihood of experiencing early menarche compared to the reference category (16-20 years), and daughters born to mothers with a longer time interval from menarche to childbirth (>20 years) have a higher likelihood of reaching early menarche.
在过去二十年中，女性的生殖寿命有所延长。与此同时，女性的生殖行为发生了变化，初育年龄增加。月经初潮过早与不良健康结果相关，但迄今为止，关于分娩时母亲年龄与女儿月经初潮年龄之间关联的研究尚无定论。母亲月经初潮至分娩之间或分娩至绝经之间的间隔是否与女儿的月经初潮年龄相关尚不清楚。
我们进行了一项队列研究，回顾性收集了参与挪威母亲、父亲和儿童队列研究的母亲和女儿的数据。在这个队列中，我们确定了两个研究人群。首先，我们纳入了14576对母女，她们拥有关于母亲月经初潮和分娩时的年龄以及女儿月经初潮年龄的完整信息。其次，我们纳入了1350对母女，她们拥有关于母亲分娩时和自然绝经时的年龄以及女儿月经初潮年龄的完整信息。我们在离散生存分析中计算了母亲月经初潮至分娩或分娩至绝经的时间间隔与女儿月经初潮年龄的比值比（OR）及其95%置信区间（CI）。我们对相关协变量进行了调整。
我们发现，与月经初潮后16至20年出生的参考类别相比，月经初潮后<16年分娩的母亲所生女儿月经初潮的年几率降低了5%（部分调整后的OR为0.95（CI 0.90 - 0.99））。在进一步调整母亲出生年份后，效应估计值进一步降低（完全调整后的OR为0.79（CI 0.74 - 0.84））。与参考类别相比，月经初潮后>20年分娩的母亲所生女儿月经初潮过早的可能性更高（完全调整后的OR为1.19（CI 1.13 - 1.27））。关于分娩至绝经的间隔，我们的研究结果在任何一个模型中均未达到统计学显著性。
与参考类别（16至20年）相比，月经初潮至分娩间隔较短（<16年）的母亲所生女儿月经初潮过早的可能性较低，而月经初潮至分娩间隔较长（>20年）的母亲所生女儿月经初潮过早的可能性较高。
