maternal age effect

The adverse impact that increased age in the mother has on obstetric events: increased complication rate; increased foetal defects, due to various effects of ageing on the uterus and eggs); and increased frequency of non-disjunctional chromosomal events in Down syndrome and other aneuploidies, as well as Prader-Willi syndrome, in which there is uniparental disomy of chromosome 15.

Maternal age and chromosome defects
[Age—Frequency of trisomy 21 (Down syndrom)—Frequency of other defects]
▪ <20—1/1900—1/526
▪ 25—1/1200—1/476
▪ 30—1/885—1/384
▪ 35—1/365—1/178
▪ 40—1/109—1/63
▪ 45—1/32—1/18
▪ 49—1/12—1/7

maternal age effect

The adverse impact that ↑ age has on obstetric events: ↑ complication rate, ↑ fetal defects–possibly due to an unknown effect of aging on the uterus and eggs; ↑ frequency of non-disjunctional events in Down syndrome and other aneuploidies, as well as Prader-Willi syndrome, in which there is uniparental disomy of chromosome 15. See Elderly primigravida. Cf Paternal age.

Maternal age & chromosome defects

Age Trisomy 21 Others

<20 1/1900 1/526

25 1/1200 1/476

30 1/885 1/384

35 1/365 1/178

40 1/109 1/63

45 1/32 1/18

49 1/12 1/7

Mentioned in

References in periodicals archive

For older mothers, the maternal age effect may be due to differential selection and accumulation of trisomy 21 oocytes in the ovarian reserve of older women.[sup][53]

Cytogenetic study of down syndrome in Algeria: Report and review

The study revealed absence of the maternal age effect on thalassemia diagnosis.

Older paternal age and positive consanguinity increase the burden of [beta] thalassemia disease

A search for evidence for a paternal age effect independent of a maternal age effect in birth certificate reports of Down's syndrome in New York State.

Incidence of down's syndrome with demographic and chromosomal pattern in Odisha

Maternal age effect had significant influences on LMR and RMR not on SMR.

Effects of age and stand density of mother trees on early pinus thunbergii seedling establishment in the coastal zone, China

"The data suggests that what at first looks seems like a negative advanced maternal age effect is an illusion driven by the mother's education and the age at which the child loses the mother," Myrskyla said.

Mum's advanced age 'doesn't harm kids' health later in life'

However, results of maternal age effects on larval energy stores and growth in the laboratory may not be an accurate predictor of success in the natural environment (Marshall et al., 2010).

Effects of maternal age and size on embryonic energy reserves, developmental timing, and fecundity in quillback rockfish (Sebastes Maliger)

Only eggs laid during this 48-h period were used in this experiment to control for maternal age effects on larval survivorship and development, in which later-laid offspring develop from smaller eggs, have lower survivorship, and take longer to develop (e.g., Wasserman and Asami 1985; Fox 1993; Fox and Dingle 1994).

Inheritance of environmental variation in body size: superparasitism of seeds affects progeny and grandprogeny body size via a nongenetic maternal effect

Unfortunately, these maternal age effects are not easily interpreted.

Are there increasing returns to the intergenerational production of human capital? Maternal schooling and child intellectual achievement