Overweight, obesity and excessive weight gain in pregnancy as risk factors for adverse pregnancy outcomes: A narrative review

Abstract

The global prevalence of overweight and obesity in pregnancy is rising and this represents a significant challenge for the management of pregnancy and delivery. Women who have a pre-pregnancy body mass index greater than 25 kg m^-2 are more likely than those with a body mass index in the ideal range (20-24.99 kg m^-2 ) to have problems conceiving a child and are at greater risk of miscarriage and stillbirth. All pregnancy complications are more likely with overweight, obesity and excessive gestational weight gain, including those that pose a significant threat to the lives of mothers and babies. Labour complications arise more often when pregnancies are complicated by overweight and obesity. Pregnancy is a stage of life when women have greater openness to messages about their lifestyle and health. It is also a time when they come into greater contact with health professionals. Currently management of pregnancy weight gain and the impact of overweight tends to be poor, although a number of research studies have demonstrated that appropriate interventions based around dietary change can be effective in controlling weight gain and reducing the risk of pregnancy complications. The development of individualised and flexible plans for avoiding adverse outcomes of obesity in pregnancy will require investment in training of health professionals and better integration into normal antenatal care.

Keywords: gestational diabetes; obesity; pre-eclampsia; pregnancy; stillbirth.

Figure 1

Obesity in pregnancy is a risk factor for adverse outcomes. BMI, body mass index. Adapted from Langley‐Evans

Figure 2

Early pregnancy body mass index (BMI) and gestational weight gain in relation to pregnancy complications (a) Distribution of BMI among severely obese pregnant women. (b) Distribution of gestational weight gain among severely obese pregnant women. All women were of BMI ≥ 35 kg m^–2 at antenatal booking (n = 387). Gestational weight gain (GWG) was determined as weight gain between booking and 36 weeks of gestation. Data are shown as median and interquartile ranges. No complications n = 291 (75% of cohort); gestational diabetes (GDM), n = 45 (11.5%); gestational hypertension (GHT), n = 37 (9.5%); pre‐eclampsia (PE), n = 16 (4%)

Figure 3

Factors that contribute to risk of pre‐eclampsia (PE) and disease progression

Figure 4

Weight gain profile for overweight women in pregnancy. The window of opportunity between antenatal booking and the rapid phase of weight gain is relatively short