Abortions May Increase Risk for Subsequent Birth Problems

August 30, 2012 — Women who have had 3 or more abortions have a higher risk for some adverse birth outcomes, such as delivering a baby prematurely or with a low birth weight, according to results from a new study conducted in Finland.

Reija Klemetti, PhD, from the National Institute for Health and Welfare in Helsinki, Finland, and colleagues report their findings in an article published online August 29 in Human Reproduction.

"Our results suggest that induced abortions [IAs] before the first birth, particularly three or more abortions, are associated with a marginally increased risk during the first birth," Dr. Klemetti noted in a news release. "However, the increased risk is very small, particularly after only one or even two abortions, and women should not be alarmed by our findings."

The effects of IAs on subsequent births have been studied, but problems with the design and variability among previous studies indicate a "clear need for further studies, particularly from countries with high-quality IA services and reliable information on IAs," Dr. Klemetti and colleagues write.

The current study sought to examine birth outcomes of firstborn children as they relate to the mothers' history of abortion. "Our hypothesis was that having one IA does not affect birth outcomes, but having several may result in poorer birth outcomes," the authors note.

The investigators analyzed birth outcomes for 300,858 first-time mothers with singleton births from 1996 to 2008. Of the mothers, 10.3% had had a single IA, 1.5% had 2, and 0.3% had 3 or more IAs before the first birth. An additional 0.08% had an unknown history of IA.

Of the IAs, 88% were surgical, 91% took place before 12 weeks of gestation, and 97% were for social reasons.

"Compared with mothers with no previous IAs, mothers with previous IAs were more often smokers, single, from urban areas and from a lower socioeconomic position, and had had miscarriages and ectopic pregnancies before their first birth," the authors write.

After adjustment for social background, women who had had 3 or more IAs had a 35% increased risk for a baby being born preterm (before 37 weeks) compared with women with no IAs. Women with 3 or more IAs also had a 125% increased risk for very low birth weight and a 43% increased risk for low birth weight compared with the no IA women.

"The study also showed a small increased risk for a baby's death around the time of birth. However, the numbers for this finding were very low (1498 births or 5/1000 babies) and so should be treated with caution," the authors say in the press release. In addition, the authors caution that they might not have been able to fully adjust for all the factors that could affect this result, and perinatal deaths are sensitive to social factors such as poverty.

"With the exception of low Apgar scores, the studied adverse birth outcomes were more common among mothers having had three or more IAs," Dr. Klemetti and colleagues conclude. "Taking into account previous miscarriages and ectopic pregnancies did not notably change the results," they add.

"Owing to the large number of IAs carried out every year, even a very small increase in risk of poor birth outcomes could have significant public health implications," the authors write. "[S]exuality education should contain information of the potential health hazards of IAs, including for subsequent pregnancies. Health care professionals should be informed about the potential risks of repeat IAs on birth outcomes in subsequent pregnancy," they add.

The authors have disclosed no relevant financial relationships.

Hum Reprod. Published online August 30, 2012.

Fonte: https://www.medscape.com