Gestational weight gain in twin pregnancies in Korea: application of the 2009 Institute of Medicine recommendations

Maternal and neonatal outcomes in women with twin pregnancies based on gestational weight gain: An updated systematic review and meta-analysis

Objective

This updated systematic review and meta-analysis aimed to assess maternal and fetal outcomes of pregnancies based on the Institute of Medicine (IOM) guidelines of gestational weight gain (GWG).

Methods

PubMED, SCOPUS, EMBASE and Web of Science were searched up to 30th July 2022. All studies evaluating maternal and/or neonatal outcomes of twin pregnancies based on the IOM guidelines of gestational weight gain were included.

Results

Twenty two studies were included. Mothers with twin pregnancies experiencing inadequate GWG showed higher incidence of gestational diabetes with the risk ratio (RR) 1.22 95% CI (0.95,1.57), p=0.0005, i2= 69% and premature rupture of membrane (PROM) with RR 1.14 95% CI (0.99, 1.30), p=0.07; i2=0% that coincided with higher rates of preterm birth, low birth weight, small for gestational age (SGA) and admission to NICU in neonates. Mothers with excessive GWG had higher risk of developing gestational hypertension with RR 1.59 95% CI (1.22, 2.07), p=0.0006, i2=75% and extremely preterm delivery (<32 weeks).

Conclusion

Within the limitations of this review, GWG was found to be a predictable risk factor for adverse maternal and neonatal outcomes of twin pregnancies.

Secular Trends of Birth Weight in Twins and Singletons in South Korea from 2000 to 2020

Whether the decline of birth weight (BW) reported in developed countries in the early 2000s is ongoing remains unknown. Furthermore, despite recent sharp increases in twin births, comparing secular trends of BW between singletons and twins is difficult, as studies have rarely examined secular trends of BW in twins and singletons simultaneously. Therefore, this study aimed to investigate the most recent 20-year trends (2000-2020) of BW in twins and singletons in South Korea. Annual natality files from 2000 to 2020 obtained from the Korean Statistical Information Service were analyzed. A yearly decrease of BW was 3 g among singletons and 5 to 6 g in twins from 2000 to 2020, indicating a widening gap of BW between twins and singletons with increasing years. Gestational age (GA) also decreased in twins and singletons with yearly decreases of 0.28 days in singletons and 0.41 days in twins. Whereas BW decreased in term (GA ≥ 37 weeks), and very preterm groups (28 weeks ≤ GA < 32 weeks) from 2000 to 2020 in twins and singletons, it increased in moderate to late preterm (32 weeks ≤ GA < 37 weeks) groups, indicating a non-linear relationship between BW and GA. The prevalence of macrosomia (BW > 4000 g) in singletons decreased from 2000 to 2020, whereas low birth weight (LBW; BW < 2500 g) increased in twins and singletons. LBW is associated with adverse health outcomes. Effective public health strategies aiming at reduction in the incidence of LBW in the population should be developed.

Associations between prepregnancy body mass index, gestational weight gain, and pregnancy outcomes in women with twin pregnancies: A five-year prospective study

BACKGROUND

The purpose of this project was to investigate the relationship between prepregnancy body mass index (ppBMI), gestational weight gain (GWG), and pregnancy outcomes in women with twin pregnancies.

METHODS

A prospective cohort of 369 women with dichorionic diamniotic twin pregnancies was recruited from 2016 to 2020. According to ppBMI using Chinese BMI classifications, they were categorized into the underweight (BMI < 18.5 kg/m² ), normal (BMI 18.5-23.9 kg/m² ), and overweight and obese (BMI ≥ 24 kg/m² ) groups. In each ppBMI group, they were divided into two subgroups based on the presence or absence of the complications such as gestational diabetes mellitus (GDM), hypertensive disorders of pregnancy (HDP), and small for gestational age (SGA). The outcomes including GDM, HDP, and SGA were compared among three ppBMI groups, and the associations of GWG with these outcomes within each ppBMI category were analyzed.

RESULTS

Twin-pregnant women with overweight and obesity were at increased risks of HDP (aOR = 4.417 [95% CI = 1.826-9.415]) and SGA (2.288 [1.102-4.751]), whereas underweight women were prone to deliver SGA newborns (2.466 [1.157-5.254]). Women with GDM gained less weight during pregnancy than those without GDM within each ppBMI category. For overweight and obese women, greater GWG increased the incidence of HDP (1.235 [1.016-1.500]) and decreased the risk of SGA (0.818 [0.702-0.953]).

CONCLUSIONS

Both ppBMI and GWG in twin-pregnant women were strongly associated with HDP and SGA, but not GDM.

Gestational weight gain adequacy among twin pregnancies in France

The objective of this paper is to describe gestational weight gain (GWG), to assess the applicability of the 2009 Institute of Medicine (IOM) guidelines, and to derive a GWG adequacy classification within a French cohort. We included twins from the national, prospective, population-based JUmeaux MODe d'Accouchement (JUMODA) cohort study (2014-2015). Following the IOM approach, we selected a 'standard' population of term pregnancies with 'optimal' birthweight (≥2500 g; n = 2562). GWG adequacy (insufficient; adequate; excessive) was defined using IOM recommendations (normal body mass index [BMI]: 16.8-24.5 kg [also utilized for underweight BMI]; overweight: 14.1-22.7 kg; obese: 11.4-19.1 kg). Additionally, using the IOM approach, we determined the 25th and 75th percentiles of GWG in our standard population to create a JUMODA-derived GWG adequacy classification. GWG and GWG adequacy were described, overall and by BMI and parity. In the JUMODA standard population of term twin livebirths with optimal birthweight, mean GWG was 16.1 kg (standard deviation 6.3). Using IOM recommendations, almost half (46.5%) of the women had insufficient and few (10.0%) had excessive GWG, with similar results regardless of BMI or parity. The 25th and 75th percentiles of GWG in the JUMODA standard population (underweight: 13-21 kg; normal weight: 13-20 kg; overweight: 11-19 kg; obese: 7-16 kg) were lower than the IOM recommendations. The IOM recommendations classified a relatively high percentage of French women as having insufficient and a low percentage as having excessive GWG. Additional research to evaluate recommendations in relation to adverse perinatal outcomes is needed to determine whether the IOM recommendations or the JUMODA-derived classification is more appropriate for French twin gestations.

Association of Optimal Gestational Weight Gain Ranges With Perinatal Outcomes Across Body Mass Index Categories in Twin Pregnancies

IMPORTANCE

The existing gestational weight gain (GWG) recommendations for twin pregnancies are lacking for underweight individuals and are not stratified by obesity class.

OBJECTIVE

To identify optimal GWG ranges associated with reduced adverse perinatal outcomes stratified by prepregnancy body mass index (BMI) categories in twin pregnancies.

DESIGN, SETTING AND PARTICIPANTS

This population-based cohort study of twin pregnancies using data from the National Center for Health Statistics was conducted between January 1, 2014, and December 31, 2018. Statistical analysis was performed from October 24, 2021, to May 7, 2022. The study population comprised 262 604 individuals between 18 and 45 years of age with live-born twins without congenital malformation between 24 and 42 weeks of gestation. Two approaches were used to determine the optimal GWG ranges: a statistics-based approach calculating IQRs of GWG in a low-risk population, and an outcome-based approach identifying GWG thresholds below or above which an adverse perinatal outcome increased.

EXPOSURE

Gestational weight gain.

MAIN OUTCOMES AND MEASURES

Preterm birth less than 36 weeks, gestational hypertensive disorders, small for gestational age status, large for gestational age status, and a composite outcome defined as any occurrence of the individual outcomes.

RESULTS

The main sample comprised 200 810 individuals with twin pregnancies (mean [SD] maternal age, 30.4 [5.5] years; 1624 [0.8%] American Indian or Alaska Native, 13 031 [6.5%] Asian or Pacific Islander, 36 423 [18.1%] Black, and 149 732 [74.6%] White; and 137 409 [68.4%] multiparous). In the low-risk subgroup (n = 61 794), the IQRs of the total GWG after 36 weeks of gestation as assessed using a statistics-based approach and based on BMI group were 15.9 to 22.7 kg for underweight, 15.4 to 22.7 kg for normal weight, 12.7 to 22.2 kg for overweight, 10.0 to 20.0 kg for class 1 obesity, 7.7 to 18.1 kg for class 2 obesity, and 5.9 to 16.3 kg for class 3 obesity. The absolute risk of the composite outcome showed U-shaped associations with GWG across BMI categories. The optimal GWG ranges by 36 weeks identified using an outcome-based approach and BMI group were 17.5 to 24.9 kg for underweight, 15.0 to 24.9 kg for normal weight, 15.0 to 24.9 kg for overweight, 10.0 to 19.9 kg for class 1 obesity, 7.5 to 17.4 kg for class 2 obesity, and 5.0 to 9.9 kg for class 3 obesity. The multivariable logistic models assessed using the validation sample (n = 49 275) showed that GWG defined outside those optimal ranges was associated with preterm birth at less than 36 weeks, gestational hypertensive disorders, and small or large for gestational age.

CONCLUSIONS AND RELEVANCE

This population-based cohort study found that optimal GWG ranges were similar for individuals with underweight and normal weight but decreased with increasing severity of obesity. The current US Institute of Medicine GWG recommendations may be too high for individuals with moderate or severe obesity.

Gestational Weight Gain in Twin Pregnancies and Maternal and Child Health: An Updated Systematic Review

Background: The Institute of Medicine (IOM) has provisional gestational weight gain (GWG) guidelines for women pregnant with twins due to limited data in this population. To better inform guidelines, the objective of this systematic review was to build on prior work and examine recent data on the associations of GWG with maternal and child health in twin pregnancies. Materials and Methods: In February 2021, Ovid MEDLINE, Embase, CINAHL, and Cochrane Library were searched. Observational studies were eligible if published from January 1, 2013 through February 23, 2021, and examined associations of GWG with maternal or child health outcomes after accounting for gestational age at delivery and pre-pregnancy body mass index. Heterogeneity across studies precluded the use of meta-analytic methods. Results: A total of 29 studies were included. For maternal outcomes, excessive GWG was associated with an increased risk of hypertensive disorders of pregnancy; whereas studies examining gestational diabetes and delivery method reported mixed findings. For child outcomes, inadequate GWG was associated with lower birthweight, small for gestational age, and preterm birth. Adequate or excessive GWG was associated with later gestational age at delivery. Conclusions: This study advances an earlier review by including a more diverse array of maternal and child outcomes. Many of the limitations noted in the original review persist; for example, no studies examined the associations of GWG and outcomes beyond birth. Although it appears that GWG within the IOM guidelines is associated with more optimal outcomes, additional methodologically rigorous studies are needed to better inform evidence-based guidelines.