Women who suffered a stillbirth during their first pregnancy are more likely than other women to lose their second pregnancy as well, a new study suggests.
The study, which examined births among all Scottish women who had their first and second pregnancies between 1981 and 2005, found that those who had a stillbirth with their first were twice as likely to suffer a stillbirth with the second.
The absolute risk, however, was still "very small," stressed lead researcher Dr Sohinee Bhattacharya, of Aberdeen Maternity Hospital in Scotland.
Among women with a previous stillbirth, 2% had another with the second pregnancy, the study found. That compared with 0.4% among women who had a previous live birth with their first pregnancy.
Stillbirths rare in developed world
"Thankfully, stillbirth is a rare occurrence in the developed world," Bhattacharya told Reuters Health in an email.
Stillbirth refers to foetal deaths that occur after the 20th week of pregnancy. Among the most common causes are birth defects, poor foetal growth and problems with the placenta - such as placental abruption, where the placenta peels away from the wall of the uterus, leading to heavy bleeding.
Certain health conditions in the mother, like diabetes and pregnancy-related high blood pressure (what doctors call pre-eclampsia) may also raise the risk of stillbirth.
Some of those causes, including placental abruption and pre-eclampsia, tend to recur - that is, women who've had the complications in their first pregnancy have a higher-than-average risk of developing them in subsequent pregnancies.
That recurrence helps explain why women with a history of stillbirth have a heightened risk of a second one, Bhattacharya said.
The findings, published in the obstetrics journal BJOG, are based on data from more than 309,000 women who had their first and second pregnancies between 1981 and 2005. Of those women, 2,677 had a stillbirth during their first pregnancy.
A history of stillbirth was related to a near-doubling in the risk of a second, taking into account factors such as the women's age, socioeconomic status and smoking.
As far as what women can do to lower the risk of stillbirth, Bhattacharya noted that certain causes of such pregnancy losses, like pre-eclampsia, are difficult to predict or prevent. But regular prenatal-care visits to monitor the pregnancy increase the likelihood that pre-eclampsia or other pregnancy complications will be detected and managed early on.
In addition, Bhattacharya said, women who smoke should quit; smoking is linked to increased risks of certain causes of stillbirth, including placental abruption and poor foetal growth.
Obese women have also been shown to have a heightened risk of stillbirth, so losing excess pounds before a second pregnancy may help lower that risk, Bhattacharya noted. - (Amy Norton/Reuters Health, July 2010)
SOURCE: http://link.reuters.com/byw96m BJOG, online June 24, 2010.