Impact of the trait anxiety during pregnancy on birth weight: an observational cohort study

Figures & data

Figure 1. Flow diagram.

Table 1. Maternal demographics, obstetric outcomes, neonatal outcomes, and data from psychosocial questionnaires (n = 107).

Variables	M ± SD
Maternal age (years)	32 ± 6
Maternal weight before pregnancy	70.5 ± 15.1
BMI before pregnancy	26.3 ± 4.9
Maternal weight gain during pregnancy	13.4 ± 5.7
STAIs	41.7 ± 10.6
STAIt	40.5 ± 7.9
MOS-SSS	87.4 ± 10.9
Gestational age at study inclusion (weeks)	17.1 ± 8.8
Gestational ate at delivery (days)	276 ± 8
Birth weight (g)	3259 ± 438
Centile of birth weight	46.83 ± 2.9
Birth length (cm)	50.1 ± 2.2
Centile of birth length	56.3 ± 29.4
Birth head circumference (cm)	34.6 ± 1.64
Centile of birth head circumference	50.5 ± 27
	N (%)
Ethnic origin
Caucasian	76 (7)
Latin American	27 (25.2)
Smokers	8 (7.5)
Nulliparous	65 (60.7)
Hypertension induced pregnancy	3 (2.8)
Gestational diabetes	8 (7.5)
High risk pregnancy	40 (37.4)
Preterm birth < 37 w	3 (2.8)
EPDS >10	28 (26.2)
Trimester of study inclusion
First trimester	37 (34.6)
Second trimester	44 (41.1)
Third trimester	26 (24.3)
New-born gender (female)
Female	59 (55.1)
Male	48 (44.8)
Birth weight below 10th centile	16 (10.3)
SCBU admission	3 (2.8)

M: Mean; SD: Standard deviation; SCBU = Special care baby unit.

Figure 2. Graphical representation of the correlation between STAIt score and birth weight percentile.

Table 2. Univariate linear regression analysis to explore a potential correlation between birth weight percentile (adjusted for gestational age at delivery and neonate gender) and risk factors.

Risk factors	Standardized coefficient	95% Coefficient Interval	p Value
Ethnicity	−.087	−15.009 to 5.771	.380
Caucasian ethnicity	.007	−12.895 to 13.985	.941
Maternal weight	.256	.155 to .998	.008
Body Mass Index (BMI)	.234	.295 to 2.721	.015
Parity	.213	1.479 to 25178	.028
Maternal weight gain	.019	−1.058 to 1.269	.858
Hypertensive disorders during pregnancy	−.075	−49.659 to 21.884	.443
Gestational Diabetes	.007	−21.657 to 23.372	.940
Tobacco	−.168	−41.738 to 2.652	.084
STAIt score	−.228	−1.599 to −.010	.047
STAIs score	−.183	−1.042 to .022	.060
EPDS score	−.147	−2.192 to .308	.138
MOS-SSS score	−.048	−.764 to .475	.645
Depression disorder	−.008	−26.796 to 24681	.935
Preterm birth < 37w	−.221	−75.966 to −5996	.022
Trimester of pregnancy	.125	−3597 to 14.119	.241
High Risk Pregnancy	.039	−9.766 to 14695	.690
Gestational age at beginning lockdown	.170	−.070 to 1157	.082

Table 3. Multivariate lineal regression analysis to explore a potential correlation between birth weight percentile (adjusted for gestational age at delivery and neonate gender) and risk factors.

Risk factors	Standardized coefficient	95% Coefficient Interval	p Value
Maternal weight	.265	.088 to 0.979	.020
STAIt score	−.220	−1.544 to −.004	.049
Tobacco	−.089	−33.90 to 14.279	.419
Parity	.131	−5.765 to 22.461	.242

Data availability statement

The data that support the findings of this study are available on request from the corresponding author, [MB]. The data are not publicly available due to [restrictions e.g. their containing information that could compromise the privacy of research participants]. The participants of this study did not give written consent for their data to be shared publicly, so this should be obtained before sharing for ethical reasons.

Contribution

• What are the novel findings of this work? This research highlights the relevance of the trait anxiety during pregnancy on fetal growth. In pregnant women, exposed to stressful circumstances in real life, the trait anxiety was found to be an independent predictor of low birth weight.

• What are the clinical implications of this work? To develop adequate strategies for early screening and treatment of anxiety symptoms and other mental health disorders during pregnancy, in order to improve the consequences of fetal growth disorders and other perinatal outcomes.