Just ONE abortion or miscarriage 'increases the risk of complications with future pregnancies'

12/08/15 Daily Mail

Just ONE abortion or miscarriage 'increases the risk of complications with future pregnancies'

  • One first-trimester loss increases the risk of future complications
  • Women in this group face higher rates of induced labour, C-sections and retained placenta - where the placenta fails to deliver after birth
  • Ending pregnancy intentionally or spontaneously made little difference
  • Experts say though effects are relatively mild, doctors should be aware

Women who go through just one abortion or miscarriage are more likely to face complications during future pregnancies, scientists have warned.

It has long been established that undergoing several abortions or enduring more than one miscarriage increase's the risk of problematic subsequent pregnancies.

Among the recognised complications, these women face higher chances of vaginal bleeding, pre-term birth, low birth weight and placenta complications.

But, a new study has now revealed those women who experience a single interruption in pregnancy during the first trimester, are 30 per cent more likely to face complications in future, than women who have not experienced a pregnancy loss.

They include higher rates of induced labour, caesarean sections and retained placenta after delivery.  

But whether the first pregnancy was ended intentionally or spontaneously made little difference. 

Researchers at Tel Aviv University, led by Dr Liran Hiersch, analysed 15,000 deliveries at Rabin Medical Center in Israel over the last five years. 

They compared the pregnancy outcomes of nulliparous women - those who experienced a single previous first-trimester interruption - with those of primigravidas women - those in their first pregnancy with no past history of abortion or miscarriage. 

They focused on women who had either a naturally occurring miscarriage, known as a spontaneous abortion, or who had what’s known as an inducted, or induced, abortion using medication or surgery.

Women were excluded if they had a history of multiple abortions or miscarriages, lacked prenatal care, were pregnant with multiples or had pregnancies complicated by stillbirth or major fetal abnormalities.

Overall, the researchers found that women with a previous pregnancy terminated by miscarriage or abortion were older.

In addition they had a higher rate of fertility treatments and were more likely to have diabetes during pregnancy than the control group of women who didn’t have a prior terminated pregnancy.

Among the women with a past terminated pregnancy, 53 per cent had miscarriages, 33 per cent had abortions and another 14 per cent didn’t have the type of termination specified in their records.

About seven per cent of women with a prior abortion or miscarriage had labour induction, compared with about five per cent of women pregnant for the first time.

 In addition, although we found that a single early pregnancy loss was associated with an increased risk for subsequent adverse pregnancy outcome, the effect was mild
Dr Liran Hiersch, Tel Aviv University 

Caesarean deliveries were performed for 25 per cent of women with a prior terminated pregnancy, compared with 18 per cent of the other women.

Retained placenta after birth - where the placenta fails to deliver - occurred with about seven per cent of women who had a history of miscarriage or abortion, compared with roughly five per cent of the other women.

But extensive bleeding, a serious side effect of the placenta failing to emerge after the baby, was rare and happened in roughly three per cent of the deliveries regardless of the women’s prior pregnancy history.

The researchers note that previous studies exploring the effect of a single pregnancy loss on future outcomes were based on incorrect assumptions. 

Past research compared outcomes between women who never gave birth before with those whose first pregnancy ended in a normal delivery, the researchers at Tel Aviv said. 

Dr Liran Hiersch, who assessed only those women who delivered their first infants and compared them with those who had only one or no pregnancy loss in their past, said: 'A history of normal pregnancy is considered protective from adverse outcomes, so this group already had an advantage over those who had pregnancy loss in their past.

'This, I believe, was the main advantage of the methodology of our study in comparison to previous reports.'

Dr Hiersch said it is important to emphasise that a single pregnancy loss is a 'very common event' during a woman's reproductive years. 

'In most cases it has no effect on future fertility or pregnancy outcome,' Dr Hiersch added. 

'In addition, although we found that a single early pregnancy loss was associated with an increased risk for subsequent adverse pregnancy outcome, the effect was mild. 

'Our findings should be taken into account together with other parameters when assessing the risk for adverse outcome.

'We hope this study will be incorporated in the usual risk assessments. 

'Doctors should know there is another element to factor in when assisting a woman before labour.' 

The researchers are currently planning to conduct a major prospective study on the subject.

The study was published in the Journal of Maternal Fetal and Neonatal Medicine.






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