Overweight and obese women at higher risk of adverse neonatal and maternal outcomes

March 26, 2013

Overweight and obese women are more likely to require specialist medical care during their pregnancy due to the increased risk of adverse neonatal and maternal outcomes, finds a new study published today (27 March) in BJOG: An International Journal of Obstetrics and Gynaecology.

The study, carried out by a team from Queen's University Belfast and Belfast Health and Social Care Trust, found that maternal obesity has significant contributing to increased morbidity and mortality for both mother and baby. With worldwide having doubled over the past 30 years, the rate of obese pregnant women is also increasing.

This study categorised women according to the (WHO) (BMI) classifications. The categories included women who were underweight (BMI <18.5), (BMI 18.5-24.9), overweight (BMI 25-39), and three obese sub-categories including obese class I (BMI 30-34.9), obese class II (BMI 35-39.9) and obese class III (BMI >40).

It looked at the impact of BMI on maternal and neonatal outcomes in 30,298 singleton pregnancies, from a referral unit in Northern Ireland, in the UK over an 8 year period (2004-2011). Within this cohort, 2.8% of women were categorised as underweight, 52.5% normal weight, 27.8% overweight, 11% obese class I, 3.9% obese class II and 1.9% obese class III.

Results showed that, when compared to normal weight women, women in the overweight and obese class I category had an increased risk of hypertensive disorders, , induction of labour, , post-partum haemorrhage and macrosomia (large birthweight baby), with all risks significantly increasing for obese class II and III women. For example, women in obese class III were four times more likely to develop gestational diabetes compared to normal weight women.

Furthermore, women in obese class III were identified to be at the most risk of additional adverse outcomes including having a , a newborn requiring neonatal admission, and stillbirth, which was three times more likely among these women.

In overweight and there was also an increased likelihood of postnatal problems, such as unsuccessful breastfeeding, which has also shown to increase the risk for long-term health implications for both mother and baby in relation to obesity.

Conversely, underweight women were at an increased risk of anaemia and were more likely to have a low birthweight baby, when compared to normal weight women.

Dr Valerie Holmes, Centre for Public Health, Queen's University Belfast and co-author of the study, said:

"This large-scale study clearly demonstrates that being overweight or obese during pregnancy increases the risk of adverse maternal and neonatal outcomes.

"By having obesity in sub-classifications, we were able to highlight the relationship between increasing BMI and the increasing risk of adverse outcomes, with women most at risk in obese class III requiring specialist medical care during pregnancy."

Dale Spence, School of Nursing and Midwifery, Queen's University Belfast and co-author of the study, added:

"We found that the majority of overweight women fall into the overweight or obese class I categories and while they are still at an increased risk of gestational diabetes and hypertensive disorders in pregnancy, they may not be offered the same level of specialist care under current guidelines."

Mike March, BJOG Deputy-Editor-in-Chief, said:

"We know that maternal obesity has significant health implications including an increased risk of developing pregnancy-related disorders, poorer labour outcomes and adverse neonatal health.

"This study further shows the relationship between obesity and these adverse outcomes by linking rising BMI with the likelihood of adverse maternal and associated with pregnancy.

"Further research is needed to optimise management for overweight and obese during pregnancy."

Explore further: Overweight moms with moderately high blood sugar raise health risk

More information: Scott-Pillai R, Spence D, Cardwell CR, Hunter A, Holmes VA. The impact of body mass index on maternal and neonatal outcomes: A retrospective study in UK Obstetric population. BJOG 2013 dx.doi.org/10.1111/1471-0528.12193

Related Stories

Overweight moms with moderately high blood sugar raise health risk

April 11, 2012
Pregnant women who are overweight with moderately elevated blood sugar never set off any alarms for their physicians. The big concern was for women who were obese or who had gestational diabetes because those conditions are ...

Obesity and extreme slimness cause risks in pregnancy

April 19, 2012
Obese women run the risk of problems during pregnancy, labour and complications for the baby's health. A new study of more than 3000 expectant mothers confirms this, and also reveals that being underweight also has specific ...

Maternal obesity increases risk of newborn death in sub-Saharan Africa where obesity is rising at alarming rate

August 8, 2012
"Sub-Saharan Africa already has the highest rates of neonatal death in the world. Whilst overall levels of obesity are currently fairly low by global standards, obesity is actually a rapidly emerging problem, with 5% of women ...

Gestational diabetes, obesity impact pregnancy outcomes

March 2, 2012
(HealthDay) -- Women with gestational diabetes mellitus (GDM) who are obese have significantly higher odds of adverse pregnancy outcomes, according to findings from the multinational Hyperglycemia and Adverse Pregnancy Outcome ...

Recommended for you

Negative birth outcomes linked to air pollution exposure early in pregnancy, study finds

July 27, 2017
Exposure to air pollution early in a pregnancy could increase risk for preterm birth and low birth weight, according to a study led by researchers at NYU School of Medicine, and published on July 27 in Environmental Health ...

Study shows a significant ongoing decline in sperm counts of Western men

July 25, 2017
In the first systematic review and meta-analysis of trends in sperm count, researchers from the Hebrew University-Hadassah Braun School of Public Health and Community Medicine and the Icahn School of Medicine at Mount Sinai ...

Women exposed to smoke while in womb more likely to miscarry

July 13, 2017
Women exposed to cigarette smoke while in their mothers' wombs are more likely to experience miscarriage as adults, according to new research from the University of Aberdeen.

Lack of a hormone in pregnant mice linked to preeclampsia

June 30, 2017
(Medical Xpress)—A team of researchers from Singapore, the Netherlands and Turkey has isolated a hormone in pregnant mice that appears to be associated with preeclampsia—a pregnancy-related condition characterized by ...

Aspirin reduces risk of pre-eclampsia in pregnant women

June 28, 2017
Taking a low-dose aspirin before bed can reduce the risk of pre-eclampsia, which can cause premature birth and, in extreme cases, maternal and foetal death.

The biology of uterine fluid: How it informs the fetus of mom's world

June 22, 2017
A developing fetus bathes in a mixture of cellular secretions and proteins unique to its mother's uterus. Before fertilization, the pH of uterine fluid helps create a conducive environment for sperm migration, and afterward, ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.