New research highlights the risks associated with being pregnant over age 35. Women age 35 and up are much more likely to have major pregnancy and birth complications, including stillbirth and other adverse outcomes, according to a study published May 30th in PLoS Medicine.
Previous research has linked advanced maternal age to complications such as gestational diabetes and preeclampsia, but this new study further elucidates some of the health issues older mothers may face, according to lead study author. Dr. Sarka Lisonkova. According to Lisonkova, “While a delay of childbirth by a few years does not make a large difference in the early thirties, a few years delay in the late forties increases the risks significantly.”
The study examined data on 828,269 women with singleton pregnancies between 2003-2013. The researchers adjusted for certain factors that can influence pregnancy (such as first-time pregnancy, obesity, and IVF use) and then compared age-specific rates of maternal death and severe complications (such as obstetric shock or amniotic fluid embolism, a condition where amniotic fluid enters the mother’s bloodstream, causing major respiratory issues).
The study found that:
- Women ages 35-39 were 20% more likely to have severe complications than mothers age 25-29.
- Mothers age 50+ have a 5x higher risk of severe complications
- Women ages 35+ were 8x likelier to have amniotic fluid embolism.
- Mother 40+ were almost 16x more likely to have kidney failure and 3x more likely to have obstetric shock
- Mothers age 40+ are 5x more likely to have complications stemming from interventions or to be admitted to an ICU
These findings link advanced maternal age to a higher risk of health complications for both the mother and baby, which may mean that mothers older than 35 may benefit from counseling to explain the relative risks of pregnancy at older ages.
This work is especially important in the United States, as the US birth rate for women ages 30-35 is higher than that of women ages 25-29. As this trend continues, older women should be aware that they may have a high-risk pregnancy and should be monitored closely by their medical care provider for complications.
- Lisonkova S et al. Maternal age and severe maternal morbidity: A population-based retrospective cohort study. PLoS Medicine. Online May 30, 2017. bit.ly/2rBYV7I