Effect of gestational weight gain on placental weight: A single tertiary referral center study of Japanese women

Abstract

AimThe effect of gestational weight gain on placental weight has not been elucidated. We aimed to examine the effect of body weight gain during pregnancy on the Japanese standardized z‐score of placental weight, based on the pre‐pregnancy body mass index.MethodsThis retrospective cohort study included Japanese women with singleton pregnancies who gave birth during 2013–2019 at Ohta Nishinouchi Hospital. Participants (n = 3610) were categorized by their pre‐pregnancy body mass index: G1 (<18.5 kg/m2), G2 (18.5 to <20.0 kg/m2), G3 (20.0 to <23.0 kg/m2), G4 (23.0 to <25.0 kg/m2), and G5 (≥25.0 kg/m2). Multiple linear regression analysis was used to identify associations between insufficient or excessive gestational weight gain in each body mass index category and z‐score of placental weight, with adjustments for maternal age, assisted reproductive technology, and maternal pre‐pregnancy conditions, such as hypertension, diabetes mellitus, myoma uteri, and uterine anomalies.ResultsAmong the 3610 women assessed, 479, 692, 1292, 435, and 711 were in G1–G5, respectively. In G1, G3, and G4, excessive weight gain increased the placental weight z‐score ([B: 0.50, 95% confidence interval [CI]: 0.23–0.76], [B: 0.19, 95% CI: 0.19–0.33], and [B: 0.18, 95% CI: 0.10–0.26]). Insufficient weight gain decreased the placental weight z‐score in G3 (B: −0.19, 95% CI: −0.33 to −0.06) and G4 (B: −0.21, 95% CI: −0.29 to −0.13) women.ConclusionThe effect of weight gain during pregnancy on placental size varies by pre‐pregnancy body mass index. This result may guide personalized pre‐conception counseling to improve the outcomes of offspring.

Effect of gestational weight gain on preeclampsia among underweight women: A single tertiary referral center study in Japanese women

“…The aforementioned suggested personalized counseling as a form of preconception care for appropriate weight gain during pregnancy to improve future neonatal health. 17 As the placenta size is more likely to be undirect obstetric event and usually confirmed after the delivery, we focused on obvious obstetrics complications, such as PE, which could be diagnosed during the perinatal period and affect both maternal and offspring health. Although we found no significant difference with regards to the gestational age at delivery between the PE and control groups, delivery tends to be early in PE cases.…”

“…We have previously reported that gestational weight gain > 13.6 kg was significantly associated with placental growth, which is calculated using the z‐score in cases of individuals with BMI < 18.5 kg/m 2 before pregnancy. The aforementioned suggested personalized counseling as a form of preconception care for appropriate weight gain during pregnancy to improve future neonatal health 17 . As the placenta size is more likely to be undirect obstetric event and usually confirmed after the delivery, we focused on obvious obstetrics complications, such as PE, which could be diagnosed during the perinatal period and affect both maternal and offspring health.…”

“…In this retrospective cohort study, medical records of women who delivered at Ohta Nishinouchi Hospital, a tertiary referral center in Fukushima, Japan, between January 1, 2013 and December 31, 2019 were evaluated. 17 The study was approved by the institutional review board of Ohta Nishinouchi Hospital (date of approval: February 26, 2021, approval no. 42), and the requirement for informed consent was waived owing to the retrospective nature of the study.…”

Gestational weight gain as a risk factor for dystocia during first delivery: a multicenter retrospective cohort study in Japan

“…Recently in Japan, gestational weight gain, based on maternal pre-pregnancy BMI, has been recognized as an important modifiable determinant of pregnancy outcomes [11][12][13][14][15]. While an association between gestational weight gain and adverse perinatal outcomes has previously been reported [11][12][13][14][15], the association between gestational weight gain and dystocia as a function of prepregnancy BMI, based on the six BMI groups, remains to be clarified.…”

“…In Japan, obesity in pregnant women is defined as a pre-pregnancy BMI ≥ 25.0 kg/m 2 [10]. Generally, BMI is categorized into the following five validated groups (G): G1, < 18.5 kg/m 2 ; G2, 18.5 to < 20.0 kg/m 2 ; G3, 20.0 to < 23.0 kg/m 2 ; G4, 23.0 to < 25.0 kg/m 2 ; G5, 25.0 to < 30.0 kg/m 2 (overweight); and G6, ≥ 30.0 kg/m 2 (obesity) [7,[11][12][13][14][15].…”