Labour outcome of low-risk multiparas of 40 years and older. A case-control study

Advanced maternal age and the risk of cesarean birth: a systematic review

BACKGROUND

The increasing pregnancy rate at advanced maternal age is contemporaneous with the increasing rate of cesarean birth. Several studies have found that advanced maternal age is a risk factor for cesarean birth. The objective of this systematic review was to assess the relationship between advanced maternal age and cesarean birth among nulliparous and multiparous women.

METHODS

To identify relevant studies, we searched the literature for articles published from January 1, 1995 to March 1, 2008, using Medline, EMBASE, PsychINFO, and CINAHL. We also hand-searched the bibliographies of retrieved articles to identify additional related studies. We included all cohort studies and all case-control studies that examined this association in developed countries. The Cochrane Collaboration's Review Manager software (5.0) was used to summarize the data.

RESULTS

Twenty-one studies met the inclusion criteria and were included in the review. All studies demonstrated an increased risk of cesarean birth among women at advanced maternal age compared with younger women, for both nulliparas and multiparas (relative risk varied from 1.39 to 2.76). Because we found extreme heterogeneity (both statistical and clinical) among the included studies, we did not provide a pooled estimate of the risk of cesarean birth.

CONCLUSIONS

All included studies illustrated an increased risk of cesarean birth among older women. Fifteen studies adjusted this association for potential confounders, which suggests that a valid and independent association is likely to exist between advanced maternal age and cesarean birth. However, the associated factors for this increased risk are not totally understood in the literature.

Long-term health consequences of delayed childbirth: NHANES III

Medicine has pointed to short-term, immediate health risks to child and mother of delaying childbearing past the age of 35 years. The long-term health consequences of delayed childbearing have not been the subject of research. Are women who delay having children to pursue education and career goals placing their later health status at risk? To address this question, the study utilizes data from the National Health and Nutrition Examination Survey III 1988-1994. The analyses used odds ratios obtained from stepwise logistic regression analysis to assess women's health risks. The results are suggestive of selective risk enhancement from delayed childbirth with regard to cardiovascular disease and risk factors, especially diabetes and hypertension, and congestive heart failure. Risks were further enhanced in terms of dental health, blood abnormalities, physical mobility, and vision difficulties. Whereas delaying childbearing may indicate a readiness on the part of women and men to delay becoming parents, the present study suggests that not all is currently known about the long-term health consequences of such decisions to delay childbearing.

Manual removal of the placenta--a case control study

The aim of this study was to determine the incidence and complications related to manual removal of the placenta in a regional hospital in Australia. The study was carried out at the Goulburn Valley Base Hospital in Shepparton. The hospital medical records were reviewed from 1992 to 1999. A total of 3734 singleton live vaginal deliveries took place during the 7-year study period. The placenta was removed manually in 114 women (3%). For a control group, a series of 113 women who had singleton live vaginal deliveries from the same period were chosen at random. The case and control groups were similar in age, parity, and gravidity. A previous history of retained placenta and a history of preterm delivery in the current pregnancy were significantly related to retained placenta (OR 9.8 [95% CI 1.1-85.5] and OR 5.6 [95% CI 1.1-26.8], respectively). The cases received significantly more blood transfusions than the control group (13% versus 0%). Decreased maternal age was also significantly related to retained placenta. There were also more post-delivery dilatation and curettage (D&C) operations and diagnosis of endomyometritis in the case group. However, these differences were not statistically significant. One woman, in the case group, had to have a hysterectomy due to placenta accreta.