Table 1 Presentation of all variables registered at first and second data entry in the Sweedish Maternal Health Care Register (MHCR)
From: Internal validity of the Swedish Maternal Health Care Register
First data entry | Second data entry | |
|---|---|---|
Data collected at first visit in antenatal care (ANC) | Data collected at postpartum visit in antenatal care (ANC) 4 to 16 weeks after delivery | |
Variables | Variables | Variables |
Date of first visit in ANC a | Live born child | Treatment of psychiatric disorder |
Country of birth | Still birth/termination of pregnancy | Questioned about exposure to violence |
No. of previous deliveries | Date of delivery estimated by ultrasound | Oral glucose tolerance test (OGTT) performed |
Maternal weight (kilograms) b | Estimated date of delivery (ultrasound) | 2-hour value of plasma glucose at OGTT (mmol/L) |
Maternal height (centimetres) b | Estimated date of delivery (last menstruation) | Diagnosis of gestational diabetes mellitus (GDM) |
Smoking three months prior to pregnancy | Ultrasound examination at gestational age 16-21 week | Date of delivery |
No. of cigarettes/day three months prior to pregnancy | Combined Ultrasound and Biochemical screening (CUB) | Maternal age at delivery |
Smoking at first ANC visit | Second trimester serum screening | Mode of delivery |
No. of cigarettes/day at first ANC visit | Chorionic villus sampling (CVS) | If caesarean section, elective or emergency section |
Use of snuff three months prior to pregnancy | Amniocentesis (AC) | Singleton birth/multiple births |
Use of snuff at first ANC visit | Number of antenatal visits until estimated date of delivery (determined by ultrasound) | Birth weight (grams) c, d |
Assessment of use of alcohol prior to pregnancy with screening instrument Alcohol Use Disorder Identification Test (AUDIT) | Number of midwives surveying the pregnant woman in ANC | Gender of infant d |
AUDIT-score | Use of authorized interpreter | Documented suspicion of intrauterine growth retardation |
Education level | Smoking at 32 weeks of gestation | Postpartum visit at ANC |
Employment status | No. of cigarettes/day at 32 gestational weeks | Date of postpartum visit at ANC |
Self-rated health prior to pregnancy | Use of snuff at 32 weeks of gestation | Maternal body weight at postpartum visit at ANC (kilograms) |
Maternal weight (in kilograms), last data entry after 35 gestational weeks | Self-rated health during pregnancy | |
Participated in prenatal education group (pregnant woman) | Self-rated health postpartum | |
Participated in prenatal education group (partner) | Breast feeding at 4 weeks postpartum | |
Counselling due to fear of childbirth | ||