Interpregnancy weight change and risk of preterm delivery

Interpregnancy weight change and neonatal and infant outcomes: A systematic review and meta-analysis

PURPOSE

To synthesize evidence regarding the association between interpregnancy weight change (IPWC) in consecutive pregnancies and neonatal or infant outcomes in the subsequent pregnancy.

METHODS

Search strategy was implemented in MEDLINE, EMBASE, Web of Science, Scopus and Cochrane Library from their inception to 13 November 2023. The most adjusted odds ratio (OR) or risk ratio estimates provided by original studies were used to calculate pooled risk ratios and their corresponding 95 % confidence intervals (CI) with the DerSimonian and Laird random effects method. Publication bias was assessed by funnel plots and Egger's method, and risk of bias was assessed with The NewcastleOttawa Quality Assessment Scale.

RESULTS

Thirty-seven observational studies were included. Interpregnancy weight loss or gain were associated with large for gestational age (OR: 0.89; 95 % CI: 0.84-0.94; I2 = 83.6 % and OR: 1.33; 95 % CI:1.26-1.40; I2 = 98.9 %), and stillbirth risk (OR: 1.10; 95 % CI: 1.01-1.18; I2 = 0.0 % and OR: 1.21; 95 % CI: 1.09-1.33; I2 = 60.2 %,).

CONCLUSIONS

Findings highlight the importance of managing weight between interpregnancy periods, although these findings should be interpreted cautiously because of the possible influence of social determinants of health and other factors.

Optimal annual body mass index change for preventing spontaneous preterm birth in a subsequent pregnancy

Preterm birth (PTB) is a leading cause of neonatal morbidity and mortality. Although PTB is known to recur, interpregnancy preventive strategies for PTB have not been established to date. Annual BMI change can serve as a specific target value for preventing obstetric complications during interpregnancy care/counseling. This value can also account for age-related weight gain (0.2 kg/m²/year). In a multicenter retrospective study, we investigated the optimal annual BMI change for preventing PTB recurrence using the data of individuals who had two singleton births from 2009 to 2019. The association between annual BMI change and spontaneous PTB (sPTB) was analyzed by separating cases of medically indicated PTB (mPTB) from those of sPTB. Previous history of sPTB was strongly associated with sPTB in the subsequent pregnancy (adjusted odds ratio [aOR], 12.7; 95% confidence interval [CI], 6.5-24.8). Increase in annual BMI was negatively associated with sPTB (aOR, 0.6; 95% CI 0.5-0.9). The sPTB recurrence rate was significantly lower in patients with an annual BMI change of ≥ 0.25 kg/m²/year than in those with an annual BMI change of < 0.25 kg/m²/year (7.7% vs. 35.0%, p = 0.011). Our findings suggest that age-related annual BMI gain between pregnancies may help prevent sPTB recurrence.

Does prepregnancy weight change have an effect on subsequent pregnancy health outcomes? A systematic review and meta-analysis

International guidelines recommend women with an overweight or obese body mass index (BMI) aim to reduce their body weight prior to conception to minimize the risk of adverse perinatal outcomes. Recent systematic reviews have demonstrated that interpregnancy weight gain increases women's risk of developing adverse pregnancy outcomes in their subsequent pregnancy. Interpregnancy weight change studies exclude nulliparous women. This systematic review and meta-analysis was conducted following MOOSE guidelines and summarizes the evidence of the impact of preconception and interpregnancy weight change on perinatal outcomes for women regardless of parity. Sixty one studies met the inclusion criteria for this review and reported 34 different outcomes. We identified a significantly increased risk of gestational diabetes (OR 1.88, 95% CI 1.66, 2.14, I²  = 87.8%), hypertensive disorders (OR 1.46 95% CI 1.12, 1.91, I²  = 94.9%), preeclampsia (OR 1.92 95% CI 1.55, 2.37, I²  = 93.6%), and large-for-gestational-age (OR 1.36, 95% CI 1.25, 1.49, I²  = 92.2%) with preconception and interpregnancy weight gain. Interpregnancy weight loss only was significantly associated with increased risk for small-for-gestational-age (OR 1.29 95% CI 1.11, 1.50, I²  = 89.9%) and preterm birth (OR 1.06 95% CI 1.00, 1.13, I²  = 22.4%). Our findings illustrate the need for effective preconception and interpregnancy weight management support to improve pregnancy outcomes in subsequent pregnancies.

Pregnancy Outcomes after Preeclampsia: The Effects of Interpregnancy Weight Change

OBJECTIVE

This study aimed to examine the effects of interpregnancy weight change on pregnancy outcomes, including recurrent preeclampsia, preterm birth, small-for-gestational age (SGA), large-for-gestational age (LGA), and cesarean delivery, among women with a history of preeclampsia. We also evaluated whether these associations were modified by prepregnancy body mass index (BMI) category in the first pregnancy (BMI < 25 vs. ≥25 kg/m²) and if associations were present among women who maintained a healthy BMI category in both pregnancies.

STUDY DESIGN

We conducted a population-based retrospective cohort study including 15,108 women who delivered their first two nonanomalous singleton live births in Missouri (1989-2005) and experienced preeclampsia in the first pregnancy. We performed Poisson regression with robust error variance to estimate relative risks and 95% confidence intervals for outcomes of interest after controlling for potential confounders.

RESULTS

Interpregnancy weight gain was associated with increased risk of recurrent preeclampsia, LGA, and cesarean delivery. These risks increased in a "dose-response" manner with increasing magnitude of interpregnancy weight gain and were generally more pronounced among women who were underweight or normal weight in the first pregnancy. Interpregnancy weight loss exceeding 1 BMI unit was associated with increased risk of SGA among underweight and normal weight women, while interpregnancy weight loss exceeding 2 BMI units was associated with reduced risk of recurrent preeclampsia among overweight and obese women.

CONCLUSION

Even small changes in interpregnancy weight may significantly affect pregnancy outcomes among formerly preeclamptic women. Appropriate weight management between pregnancies has the potential to attenuate such risks.

KEY POINTS

· Interpregnancy weight change among formerly preeclamptic women significantly affects pregnancy outcomes.. · Interpregnancy weight gain is associated with increased risk of recurrent preeclampsia, large-for-gestational-age and cesarean delivery.. · Interpregnancy weight loss is associated with increased risk of small-for-gestational age and recurrent preeclampsia..

The Impact of Gestational Weight Gain on the Risks of Adverse Maternal and Infant Outcomes among Normal BMI Women with High Triglyceride Levels during Early Pregnancy

A high maternal triglyceride (mTG) level during early pregnancy is linked to adverse pregnancy outcomes, but the use of specific interventions has been met with limited success. A retrospective cohort study was designed to investigate the impact of gestational weight gain (GWG) on the relationship between high levels of mTG and adverse pregnancy outcomes in normal early pregnancy body mass index (BMI) women. The patients included 39,665 women with normal BMI who had a singleton pregnancy and underwent serum lipids screening during early pregnancy. The main outcomes were adverse pregnancy outcomes, including gestational hypertension, preeclampsia, gestational diabetes, cesarean delivery, preterm birth, and large or small size for gestational age (LGA or SGA) at birth. As a result, the high mTG (≥2.05mM) group had increased risks for gestational hypertension ((Adjusted odds ratio (AOR), 1.80; 95% CI, 1.46 to 2.24)), preeclampsia (1.70; 1.38 to 2.11), gestational diabetes (2.50; 2.26 to 2.76), cesarean delivery (1.22; 1.13 to 1.32), preterm birth (1.42, 1.21 to 1.66), and LGA (1.49, 1.33 to 1.68) compared to the low mTG group, after adjustment for potential confounding factors. Additionally, the risks of any adverse outcome were higher in each GWG subgroup among women with high mTG than those in the low mTG group. High mTG augmented risks of gestational hypertension, preeclampsia, preterm birth, and LGA among women with 50th or greater percentile of GWG. Interestingly, among women who gained less than the 50th percentile of GWG subgroups, there was no relationship between high mTG level and risks for those pregnancy outcomes when compared to low mTG women. Therefore, weight control and staying below 50th centile of the suggested GWG according to gestational age can diminish the increased risks of adverse pregnancy outcomes caused by high mTG during early pregnancy.

Maternal weight change between successive pregnancies: an opportunity for lifecourse obesity prevention

Maternal obesity is a major risk factor for adverse health outcomes for both the mother and the child, including the serious public health problem of childhood obesity which is globally on the rise. Given the relatively intensive contact with health/care professionals following birth, the interpregnancy period provides a golden opportunity to focus on preconception and family health, and to introduce interventions that support mothers to achieve or maintain a healthy weight in preparation for their next pregnancy. In this review, we summarise the evidence on the association between interpregnancy weight gain with birth and obesity outcomes in the offspring. Gaining weight between pregnancies is associated with an increased risk of large-for-gestational age (LGA) birth, a predictor of childhood obesity, and weight loss between pregnancies in women with overweight or obesity seems protective against recurrent LGA. Interpregnancy weight loss seems to be negatively associated with birthweight. There is some suggestion that interpregnancy weight change may be associated with preterm birth, but the mechanisms are unclear and the direction depends if it is spontaneous or indicated. There is limited evidence on the direct positive link between maternal interpregnancy weight gain with gestational diabetes, pre-eclampsia, gestational hypertension and obesity or overweight in childhood, with no studies using adult offspring adiposity outcomes. Improving preconception health and optimising weight before pregnancy could contribute to tackling the rise in childhood obesity. Research testing the feasibility, acceptability and effectiveness of interventions to optimise maternal weight and health during this period is needed, particularly in high-risk and disadvantaged groups.

The impact of interpregnancy weight change on perinatal outcomes in women and their children: A systematic review and meta-analysis

Prepregnancy overweight and obesity are associated with higher risk of perinatal complications. However, the effect of weight change prior to pregnancy on perinatal outcome is largely unknown. Therefore, it is aimed to examine the impact on perinatal outcomes of interpregnancy BMI change in women of different BMI categories. The MEDLINE, EMBASE, LILACS, and CINAHL databases were searched (1990-August 2019). Observational studies on interpregnancy BMI change were selected. Outcomes evaluated were gestational diabetes mellitus (GDM), preeclampsia, gestational hypertension (GH), cesarean section, preterm birth, and newborns being large (LGA) or small (SGA) for gestational age. Meta-analyses and meta-regression analyses were executed. Thirty studies were included (n > 1 million). Interpregnancy BMI gain was associated with a higher risk of GDM (for BMI gain ≥3 kg/m² : OR 2.21; [95%CI 1.53-3.19]), preeclampsia (1.77 [1.53-2.04]), GH (1.78 [1.61-1.97]), cesarean section (1.32 [1.24-1.39]), and LGA (1.54 [1.28-1.86]). The effects of BMI gain were most pronounced in women with BMI <25 kg/m² before the first pregnancy regarding GDM, GH, and cesarean section. Except for LGA, interpregnancy BMI loss did not result in a decreased risk of perinatal complications. In this study, women of normal weight who gain weight before pregnancy were identified as a high-risk population for perinatal complications. This emphasizes that weight management is important for women of all BMI categories and a pregnancy wish.

Maternal interpregnancy weight change and premature birth: Findings from an English population-based cohort study

Background

The relationship between maternal weight change between pregnancies and premature birth is unclear. This study aimed to investigate whether interpregnancy weight change between first and second, or second and third pregnancy is associated with premature birth.

Methods

Routinely collected data from 2003 to 2018 from one English maternity centre was used to produce two cohorts. The primary cohort (n = 14,961 women) consisted of first and second live-birth pregnancies. The secondary cohort (n = 5,108 women) consisted of second and third live-birth pregnancies. Logistic regression models were used to examine associations between interpregnancy BMI change and premature births adjusted for confounders. Subgroup analyses were carried out, stratifying by initial pregnancy BMI groups and analysing spontaneous and indicated premature births separately.

Results

In the primary cohort, 3.4% (n = 514) of births were premature compared to 4.2% (n = 212) in the secondary cohort, with fewer indicated than spontaneous premature births in both cohorts.

Primary cohort

Weight loss (>3kg/m²) was associated with increased odds of premature birth (adjusted odds ratio (aOR):3.50, 95% CI: 1.78–6.88), and spontaneous premature birth (aOR: 3.34, 95%CI: 1.60–6.98), in women who were normal weight (BMI 18.5-25kg/m²) at first pregnancy. Weight gain >1kg/m² was not associated with premature birth regardless of starting BMI.

Secondary cohort

Losing >3kg/m² was associated with increased odds of premature birth (aOR: 2.01, 95%CI: 1.05–3.87), when analysing the whole sample, but not when restricting the analysis to women who were overweight or obese at second pregnancy.

Conclusions

Normal-weight women who lose significant weight (>3kg/m²) between their first and second live pregnancies have greater odds of premature birth compared to normal-weight women who remain weight stable in the interpregnancy period. There was no evidence of association between weight change in women who were overweight or obese at the start of their first pregnancy and premature birth.

The Risks Associated With Obesity in Pregnancy

BACKGROUND

Approximately one-third of all women of childbearing age are overweight or obese. For these women, pregnancy is associated with increased risks for both mother and child.

METHODS

This review is based on pertinent publications retrieved by a selective search of PubMed, with special attention to current population-based cohort studies, systematic reviews, meta-analyses, and controlled trials.

RESULTS

Obesity in pregnancy is associated with unfavorable clinical outcomes for both mother and child. Many of the risks have been found to depend linearly on the body-mass index (BMI). The probability of conception declines linearly, starting from a BMI of 29 kg/m2, by 4% for each additional 1 kg/m2 of BMI (hazard ratio 0.96, 95% confidence interval: [0.91; 0.99]). A 10% increase of pregravid BMI increases the relative risk of gestational diabetes and that of preeclampsia by approximately 10% each. A 5 kg/m2 increase of BMI elevates the relative risk of intrauterine death to 1.24 [1.18; 1.30]. An estimated 11% of all neonatal deaths can be attributed to the consequences of maternal overweight and obesity. Nonetheless, in most randomized controlled trials, nutritional and lifestyle interventions did not bring about any clinically relevant reduction in the incidence of gestational diabetes and fetal macrosomia.

CONCLUSION

The risks associated with obesity in pregnancy cannot necessarily be influenced by intervention. Preventive measures aimed at normalizing body weight before a woman becomes pregnant are, therefore, all the more important.

Interpregnancy change in body mass index and infant outcomes in Texas: a population-based study

Background

Maternal prepregnancy body mass index (BMI) is associated with several infant outcomes, but it is unclear whether these associations reflect causal relationships. We conducted a study of interpregnancy change in BMI (IPC-BMI) to improve understanding of the associations between BMI and large for gestational age (LGA), small for gestational age (SGA), and preterm birth (PTB).

Methods

Birth certificate data from 2481 linked sibling pairs (Texas, 2005–2012) were used to estimate IPC-BMI and evaluate its association with LGA, SGA, and PTB in the younger sibling of the pair. Multivariable logistic regression was used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) using data from the full sample and within strata defined by prepregnancy BMI for the older sibling.

Results

On average, women gained 1.1 BMI units between pregnancies. In the full sample, interpregnancy BMI decreases were associated with reduced odds of LGA and increased odds of SGA and PTB (IPC-BMI < -1 versus 0 to < 1: LGA aOR 0.7, 95% CI 0.4, 1.1; SGA aOR 1.6, 95% CI 1.0, 2.7; PTB aOR 1.9, 95% CI 1.3, 2.8). In stratified analyses, similar associations were observed in some, but not all, strata. Findings for interpregnancy BMI increases were less consistent, with little evidence for associations between these outcomes and the most extreme IPC-BMI increases.

Conclusions

There is growing evidence that interpregnancy BMI decreases are associated with LGA, SGA, and PTB. However, taken as a whole, the literature provides insufficient evidence to establish causal links between maternal BMI and these outcomes.

Exploring Healthy Eating and Exercise Behaviors Among Low-Income Breastfeeding Mothers

BACKGROUND:

Postpartum weight retention is often a significant contributor to overweight and obesity. Lactation is typically not sufficient for mothers to return to pre-pregnancy weight. Modifiable health behaviors (e.g., healthy eating and exercise) are important for postpartum weight loss; however, engagement among mothers, especially those who are resource-limited, is low. A deeper understanding of low-income breastfeeding mothers' healthy-eating and exercise experience, a population that may have unique motivators for health-behavior change, may facilitate creation of effective intervention strategies for these women.

RESEARCH AIM:

To describe the healthy-eating and exercise experiences of low-income postpartum women who choose to breastfeed.

METHODS:

Focus group discussions were conducted with low-income mothers ( N = 21) who breastfed and had a child who was 3 years old or younger. Transcript analysis employed integrated grounded analysis using both a priori codes informed by the theory of planned behavior and grounded codes.

RESULTS:

Three major themes were identified from five focus groups: (a) Mothers were unable to focus on their own diet and exercise due to preoccupation with infant needs and more perceived barriers than facilitators; (b) mothers became motivated to eat healthfully if it benefited the infant; and (c) mothers did not seek out information on maternal nutrition or exercise but used the Internet for infant-health information and health professionals for breastfeeding information.

CONCLUSION:

Low-income breastfeeding mothers may be more receptive to nutrition education or interventions that focus on the mother-infant dyad rather than solely on maternal health.

Association between maternal body mass index in early pregnancy and anorexia nervosa in daughters

BACKGROUND

The etiology of anorexia nervosa is poorly understood. Although genetic factors play a major role, maternal factors, and obstetric complications are possible environmental causes. We investigated the association between maternal overweight and obesity in early pregnancy and risk of anorexia nervosa in daughters.

METHODS

A retrospective cohort study including all live singleton females born in Sweden from 1992 through 2002. Anorexia nervosa diagnosis was identified by using the nation-wide Swedish Patient and Cause of Death Registers. Multivariable Cox hazards regression was used to estimate adjusted hazard ratios (aHRs) and 95% CIs, adjusting for confounders. Stratified Cox regressions were applied to data on siblings to adjust for unmeasured familial confounding.

RESULTS

Among 486,688 live singleton females, 2,414 (0.50%) were diagnosed with anorexia nervosa through 2012. The aHR of anorexia nervosa decreased linearly by maternal BMI (p-value for trend < .001). When compared with daughters of normal weight mothers (body mass index [BMI] 18.5-24.9), aHRs (95%CI) of anorexia nervosa were 0.74 (0.65-0.84) in daughters of overweight mothers (BMI 25-29.9) and 0.61 (0.47-0.78) in daughters of mothers with obesity Grade I (BMI 30-34.9). In sibling control analysis, no associations were observed between maternal BMI and aHRs of anorexia nervosa in offspring.

CONCLUSIONS

The rate of anorexia nervosa decreased with maternal overweight and obesity in a dose-response manner. However, the sibling control analysis suggests that these findings are not consistent with causals effects of maternal BMI on anorexia nervosa in offspring.

e-Health and new moms: Contextual factors associated with sources of health information

OBJECTIVE

Guided by the Uses and Gratifications approach, to examine mothers' use and preference of e-Health media, and associated contextual factors.

DESIGN AND SAMPLE

Cross-sectional survey of 165 mothers (White, African-American, and Hispanic) from a stratified random sample.

MEASURES

Use of online media about mother-baby care; favorite websites about motherhood and best-liked features of Web sites; channel preferences (Web site, postal mail, text) for receiving three types of health information; and contextual factors, e.g., education.

RESULTS

Media use ranged from 96% for health information searches about babies to 46% for YouTube viewing about mother-baby topics. Contextual factors, such as education, were associated with media use. Babycenter was the most frequently reported favorite Web site and rich, relevant information was the best-liked feature. Across three health topics (weight, stress/depression, parenting) mothers preferred receiving information by Web site, followed by postal mail and least by text messaging (χ² statistics, p < .001). Stress and race/ethnicity were among factors associated with preferences.

CONCLUSIONS

Mothers widely used e-Health related media, but use was associated with contextual factors. In public health efforts to reach new mothers, partnering with mother-favored Web sites, focusing on audience-relevant media, and adopting attributes of successful sites are recommended strategies.

Weight change across the start of three consecutive pregnancies and the risk of maternal morbidity and SGA birth at the second and third pregnancy

BACKGROUND

Weight-change across parities and/or current BMI may influence maternal and fetal morbidity and requires to be differentiated to better inform weight-management guidance.

METHODS

Direction, pattern and magnitude of weight-change across three consecutive parities and thereby two inter-pregnancy periods was described in 5079 women. The association between inter-pregnancy weight-change versus current BMI and adverse maternal events, SGA-birth and preterm delivery at second and third pregnancy were investigated by logistic regression.

RESULTS

More women gained weight across the defined childbearing period than lost it, with ~35% of normal and overweight women gaining sufficient weight to move up a BMI-category. Nine patterns of weight-change were defined across two inter-pregnancy periods and 50% of women remained weight-stable throughout (within 2BMI units/period). Women who were overweight/obese at first pregnancy had higher risk of substantial weight-gain and loss (>10kg) during each of two inter-pregnancy periods. Inter-pregnancy weight-gain (> 2BMI units) between first and second pregnancy increased the risk of maternal morbidity (1or more event of hypertensive disease, caesarean-section, thromboembolism) at second pregnancy, while weight-loss (>2BMI units) increased the risk of SGA-birth. Similarly, increased risk of maternal morbidity at the third pregnancy was influenced by weight-gain during both inter-pregnancy periods but not by current BMI-category. Both weight-gain between first and second pregnancy, and being overweight/obese by third pregnancy protected the fetus against SGA-birth whereas weight-loss between second and third pregnancy doubled the SGA risk.

CONCLUSION

Half the women studied exhibited significant weight-fluctuations. This influenced their risk of maternal morbidity and SGA-birth at second and third pregnancy.

The INTERGROWTH-21st gestational weight gain standard and interpregnancy weight increase: A population-based study of successive pregnancies

OBJECTIVE

To link the INTERGROWTH-21st gestational weight gain standard with the risks of excess maternal postpartum weight retention, approximated by women's weight change between successive pregnancies.

METHODS

A population-based retrospective cohort study of 58,534 women delivering successive pregnancies in British Columbia, Canada (2000-2015) was conducted. Pregnancy weight gain (kg) in the index pregnancy was converted into a gestational age-standardized z-score using the INTERGROWTH-21st standard. Excess interpregnancy weight gain was defined as weight increases of 5 kg, 10 kg, or obesity (≥30 kg/m² ) at the next pregnancy. Weight gain z-scores and excess interpregnancy weight change were associated using logistic regression.

RESULTS

For all definitions of excess interpregnancy weight gain, risks remained low and stable below a weight gain z-score of 0 (50th percentile) but rose sharply with increasing z-scores above zero. Compared with women gaining -1 to 0 SD (16th to 50th percentiles), women gaining > 0 to +1 SD (51st to 84th percentiles) were 55% to 84% more likely to retain excess weight between pregnancies. Risks were three- to sixfold higher in women gaining >+1 SD.

CONCLUSIONS

A large range of the INTERGROWTH-21st percentiles were associated with increased risks of excess interpregnancy weight gain. The standard may normalize high weight gains of women at increased risk of excess weight retention.

Women's Perceived Reasons for Their Excessive Postpartum Weight Retention: A Qualitative Interview Study

Introduction

Obesity in Sweden has doubled to 14% over the last 20 years. New strategies for treatment and prevention are needed. Excessive gestational weight gain has been found to contribute substantially to obesity, and there is a consistent association between postpartum weight retention and obesity later in life. We aimed to explore what factors women perceive as reasons for having substantial postpartum weight retention, to identify areas for new and improved interventions.

Methods

Qualitative interview study (semi-structured) using an emergent design. Fifteen women, with a postpartum weight retention ≥ 10 kg, were interviewed by a trained cognitive therapist. Eight women had pre-pregnancy BMI below 30 kg/m². Interviews were transcribed verbatim and data analysed using inductive manifest content analysis. Salient text passages were extracted, shortened, coded and clustered into categories.

Results

Participants reported no knowledge of current gestational weight gain recommendations or of risks for adverse pregnancy outcomes with excessive weight gain or postpartum weight retention. Excessive eating emerged as a common strategy to provide relief of psychological, emotional and physical discomfort, such as depression and morning sickness. Women perceived medical staff as being unconcerned about weight, and postpartum weight loss support was scarce or absent. Some women reported eating more due to a belief that breastfeeding would automatically lead to weight loss.

Conclusion

There is a need to raise awareness about risks with unhealthy gestational weight development and postpartum weight retention in women of childbearing age. The common strategy to cope with psychological, emotional or physical discomfort by eating is an important factor to target with intervention. The postpartum year is a neglected period where additional follow-up on weight and weight loss support is strongly indicated.