As Scotland, the risk of intrapartum stillbirth

As with other reported studies, we did not find the
association between AMA and preterm births or other adverse fetal outcomes. Primiparity
was related with reduced neonatal NICU admission rate in AMA2 group. Higher BMI
elevated the risk of preterm birth and low birth weight in women aged 35-39
years, but had no effect in women aged ? 40 years. The
variables influencing prematurity and neonatal outcomes are complex and
multifactorial. Studies from European and American countries
found neonatal adverse outcomes were not higher in older mothers, some even
found an inverse relationship of preterm births and maternal age14,53. Possibilities
for better fetal outcome are that the prenatal care for advanced aged women may
be better because of higher socioeconomic status and more disciplined maternal behaviour
during pregnancy. The favourable birth outcomes in AMA mothers may also reflect
survivorship of healthier embryos or fetus. AMA women suffered from
infertility, miscarriage and very preterm birth12,19.
Therefore, being the survivors of more healthy groups after natural selection,
the newborns of older women may be at a lower risk of adverse pregnancy
outcomes. However, all of the
4 stillbirths in our study were happened in mothers aged 40 and above. 3 cases
were in mothers with severe pregnancy complications and one happened during labour.
The stillbirth rate in women aged 40 and above ranged from 0.5% to 5.5% in
different studies12,16,54,55. The total stillbirth rate in China in the year 2015 was
5.4‰, in urban population the rate was 3.3‰9.In
Scotland, the risk of intrapartum stillbirth and neonatal death with cephalic
presentation at term between 1985 and 2004 was 7.7‰. More than 60% of these
cases happened because of intrapartum anoxia56.
They also found women aged 40 and above had greater than a 2 fold increased
risk of delivery related perinatal death. This evidence verified the
risk-averse choice of CS instead of vaginal delivery in doctors on the other
hand. To reduce the risk of stillbirth, comprehensive prenatal care should be implemented
in AMA mothers. Intensive monitoring and adequate preparation are needed during
labor, especially in patients aged ? 40 years.