Health implications of aging motherhood

Background. In developed countries, postponing of childbearing has become common. We studied the health and health service impacts of delayed motherhood. Methods. All first births in Finland in 2008 (n= 23 511) and 1991 (n=26 373) from medical birth register were included. Mothers 35+ years were compared to mothers 20-34 years; for perinatal health socioeconomic position, urbanity, marital status, smoking and previous pregnancies were adjusted. Births in years 2005-2009 were pooled to study the threshold age for increased problems. Results. The proportion of births to women 35+ years increased from 1991 (5.8%) to 2008 (10.4%). In 2008 older mothers had used more antenatal care, had more chronic and pregnancy related diseases, more interventions, and poorer perinatal health than younger mothers; short gestation length was not more common. Results in 1991 were similar, but short gestation was more common among older women. The preliminary age-specific results did not suggest any clear one threshold. Some problems increased steadily since 20 years (cesarean section), slightly since 30 years (induction of labor), slightly since 31-34 years (many antenatal visits, inpatient stay before birth, long postpartum hospital stay, gestation length <37weeks, birth weight < 2500g, newborn care in special unit), or rapidly since 31-34 years (gestational diabetes and hypertension). Conclusions. The results suggest that the extra problems among older first-time mothers are not strongly dependent on how common older motherhood was or on increasing medical knowledge and technology. Most problems increased since early 30s. More detailed analysis of threshold age for problems will be made.