Background
Methods
Study design
Setting
Participants
Inclusion criteria | 1. Registered as a patient with a participating general practice |
2. Female | |
3. Aged 18 to 48 years | |
4. Main spoken language coded as English | |
Exclusion criteria | 1. Current pregnancy known to the patient’s general practice |
2. Having a condition causing permanent infertility (e.g., hysterectomy, tubal ligation, menopause) | |
3. Having an enduring condition involving profound cognitive impairment (e.g., severe developmental language disorder or disorder of intellectual development) likely to introduce major difficulties in understanding the questionnaire and/or its purpose | |
4. Likely to be distressed by pregnancy-related content (e.g. pregnancy loss at any stage in the last 3 months, perinatal mortality ever) |
Variables and measurement
Preconception risk factor | Evidence certaintya | Accepted responses |
---|---|---|
Folic acid supplementation | High | Explicitly mentions folic acid/folate or a multivitamin containing folic acid as something to do/start/continue before pregnancy |
Physical activity | Moderate | Mentions physical activity, exercise or a specific form of exercise (e.g. swimming, yoga) as something to do/start/continue before pregnancy, or inactivity or sedentarism as something to avoid. |
Body mass index (BMI) /weight | Mentions BMI, ‘healthy’ weight, underweight, overweight or obesity, loss of ‘excess’ weight, or avoiding over- or undereating | |
Interpregnancy weight change | Mentions change in weight (loss or gain) from a previous pregnancy | |
Excess iron intake | Low | Mentions excess iron as something to avoid |
Diet (Mediterranean/ high Alternate Healthy Eating Index [AHEI]) | Explicitly mentions either of these diets, one or more of their key components (e.g. fruit, vegetable, legume, seed/nut, bean, cereal, grain, fish or unsaturated fat intake as positives or high meat, saturated fat, sodium or added sugar intake as negatives), or the importance of a ‘good’ or ‘healthy’ diet | |
Abuseb | Mentions domestic abuse, violence, or ‘(un)safe’, ‘hostile’ or ‘toxic’ relationships | |
Age | Mentions maternal age | |
Interpregnancy intervals | Mentions ‘time since last child’ or ‘family planning i.e. spacing of children’ |
Study size and statistical methods
Results
Participant characteristics
Descriptive data
Variable | Response categories | Study sample | National population | ||
---|---|---|---|---|---|
N | (%) | (%) | Data source (year; country) | ||
Age (years) | 18–19 | 26 | 3.1 | -a | Office for National Statistics (2020; England) [40] |
20–24 | 120 | 14.4 | 15.8 | ||
25–29 | 275 | 32.9 | 17.2 | ||
30–34 | 131 | 15.7 | 17.4 | ||
35–39 | 139 | 16.6 | 17.1 | ||
40–44 | 95 | 11.4 | 15.9 | ||
45–48 | 49 | 5.9 | 16.6b | ||
Missing | 0 | 0.0 | |||
Household income (£) | Less than 13,000 | 53 | 6.5 | 6 | Office for National Statistics (2020; United Kingdom) [39] |
13,000-18,999 | 53 | 6.5 | 10 | ||
19,000-25,999 | 85 | 10.4 | 15 | ||
26,000-31,999 | 71 | 8.7 | 12 | ||
32,000-47,999 | 142 | 17.4 | 24 | ||
48,000-63,999 | 158 | 19.4 | 15 | ||
64,000-95,999 | 161 | 19.7 | 12 | ||
More than 96,000 | 93 | 11.4 | 7 | ||
Missing | 19 | 2.3 | |||
Ethnicity | White | 767 | 92.6 | 84.3 | Office for National Statistics (2019; England) [41] |
Mixed/Multiple ethnic groups | 27 | 3.3 | 1.9 | ||
Asian/Asian British | 19 | 2.3 | 8.3 | ||
Black/African/Caribbean/ Black British | 13 | 1.6 | 3.7 | ||
Other ethnic group | 2 | 0.2 | 1.9 | ||
Missing | 7 | 0.8 | |||
Education | University | 569 | 68.6 | 41.9 | Office for National Statistics (2017; United Kingdom) [42] |
Intermediate | 185 | 22.3 | 9.4 | ||
Secondary school | 64 | 7.7 | 40.7 | ||
Primary school or less | 2 | 0.2 | 8.0 | ||
Still in education | 9 | 1.1 | -c | ||
Missing | 6 | 0.7 | |||
Country of birth | The UK | 759 | 91.9 | 84.3 | Office for National Statistics (2019; England) [43] |
Other | 67 | 8.1 | 15.7 | ||
Missing | 9 | 1.1 | |||
Ever pregnant | Previously pregnant | 404 | 48.4 | – | Not available |
Never pregnant | 430 | 51.6 | – | ||
Missing | 1 | 0.1 | |||
Previous live birth(s) | Yes | 324 | 38.8 | – | Not available |
No | 510 | 61.1 | – | ||
Missing | 1 | 0.1 | |||
Adverse pregnancy outcome(s) | Yes d | 140 | 16.8 | – | Not available |
No | 694 | 83.2 | – | ||
Missing | 1 | 0.1 | |||
Previous infertility | Yes e | 88 | 10.6 | 12.5 | Datta et al. (2010–2012; Britain) – 8869 women aged 16 to 74 years [44] |
No | 745 | 89.4 | 87.5 | ||
Missing | 2 | 0.2 | |||
Pregnancy intentions | Currently trying to become pregnant | 50 | 6.1 | – | Not available |
Would like to get pregnant in the next 1–2 years | 144 | 17.5 | – | ||
Would like to get pregnant in the next 3+ years | 183 | 22.3 | – | ||
Not sure/Don’t know | 209 | 25.5 | – | ||
Would definitely not like (more) children/Unable to get pregnant | 235 | 28.6 | – | ||
Missing | 14 | 1.7 |
Knowledge
Evidence certaintya | Preconception risk factor | N | % (95% confidence interval) |
---|---|---|---|
High | Folic acid supplementation | 275 | 32.9 (29.8–36.2) |
Moderate | Physical activity | 661 | 79.2 (76.3–81.8) |
Body mass index (BMI)/weight | 335 | 40.1 (36.8–43.5) | |
Interpregnancy weight change | 0 | 0.0 (0.0–0.0) | |
Low | Excess iron intake | 0 | 0.0 (0.0–0.0) |
Diet | 718 | 86.0 (83.4–88.2) | |
Abuse | 53 | 6.3 (4.9–8.2) | |
Age | 49 | 5.9 (4.5–7.7) | |
Interpregnancy intervals | 2 | 0.2 (0.1–1.0) |
Folic acid | Physical activity | Body mass index | Diet | Abusea | Age | |
---|---|---|---|---|---|---|
Age | ||||||
18–24 years | (reference) | (reference) | (reference) | (reference) | (reference) | (reference) |
25–29 years | 1.59 (0.87–2.88) | 0.85 (0.51–1.41) | 1.56 (0.98–2.48) | 0.72 (0.38–1.37) | 0.45 (0.18–1.12) | 1.29 (0.51–3.24) |
30–34 years | 3.42 (1.79–6.52) ‡ | 1.89 (0.94–3.78) | 1.84 (1.06–3.18) § | 0.93 (0.42–2.06) | 0.89 (0.33–2.40) | 1.05 (0.33–3.38) |
35–39 years | 4.77 (2.41–9.43) ‡ | 1.28 (0.64–2.58) | 1.44 (0.80–2.60) | 0.67 (0.29–1.52) | 0.84 (0.29–2.45) | 1.68 (0.52–5.42) |
40–48 years | 4.30 (2.10–8.80) ‡ | 1.27 (0.61–2.62) | 1.77 (0.95–3.29) | 0.61 (0.26–1.45) | 0.41 (0.12–1.35) | 1.30 (0.36–4.67) |
Income | ||||||
< £19,000 | (reference) | (reference) | (reference) | (reference) | (reference) | (reference) |
£19,000–£25,999 | 0.83 (0.40,1.71) | 1.00 (0.51–1.96) | 0.92 (0.48–1.79) | 1.35 (0.58–3.13) | 1.13 (0.36–3.60) | 1.07 (0.32–3.57) |
£26,000–£31,999 | 0.82 (0.38–1.76) | 1.67 (0.78–3.54) | 1.27 (0.66–2.47) | 2.68 (0.93–7.70) | 1.09 (0.33–3.61) | 0.40 (0.08–2.10) |
£32,000–£47,999 | 1.01 (0.55–1.87) | 1.50 (0.81–2.76) | 1.38 (0.79–2.42) | 1.25 (0.61–2.56) | 0.66 (0.22–1.95) | 0.66 (0.20–2.14) |
£48,000–£63,999 | 1.35 (0.73–2.49) | 1.47 (0.79–2.74) | 1.80 (1.03–3.15) § | 1.25 (0.60–2.60) | 0.91 (0.32–2.61) | 0.92 (0.30–2.80) |
£64,000–£95,999 | 1.25 (0.67–2.31) | 1.64 (0.86–3.10) | 1.93 (1.10–3.39) § | 1.26 (0.60–2.62) | 0.75 (0.25–2.24) | 1.11 (0.37–3.32) |
≥ £96,000 | 1.20 (0.61–2.38) | 1.39 (0.67–2.87) | 3.11 (1.65–5.84) ‡ | 1.15 (0.50–2.64) | 0.48 (0.12–1.89) | 1.36 (0.41–4.54) |
Education | ||||||
School | (reference) | (reference) | (reference) | (reference) | (reference) | (reference) |
Intermediate | 1.58 (0.78–3.22) | 0.61 (0.30–1.22) | 1.16 (0.62–2.16) | 0.84 (0.35–1.99) | 0.59 (0.21–1.69) | 0.70 (0.20–2.44) |
University | 2.37 (1.21–4.64) § | 1.18 (0.59–2.35) | 0.92 (0.51–1.65) | 1.06 (0.46–2.44) | 0.63 (0.23–1.72) | 0.74 (0.22–2.42) |
Minority ethnicityb | 0.89 (0.50–1.58) | 0.74 (0.40–1.36) | 0.82 (0.48–1.40) | 1.04 (0.48–2.26) | 0.47 (0.11–2.01) | 0.50 (0.12–2.11) |
Born outside the UKb | 0.52 (0.29–0.94) § | 1.72 (0.80–3.70) | 0.62 (0.36–1.08) | 1.57 (0.66–3.78) | 0.44 (0.10–1.88) | 2.12 (0.89–5.05) |
Ever pregnantb | 2.48 (1.70–3.62) ‡ | 1.19 (0.76–1.84) | 1.10 (0.77–1.56) | 1.20 (0.73–1.97) | 1.99 (0.96–4.14) | 0.46 (0.22–0.99) § |
Previous live birth(s)b | 2.18 (1.47–3.22) ‡ | 0.98 (0.61–1.57) | 1.27 (0.87–1.85) | 1.20 (0.70–2.03) | 2.15 (1.00–4.62) | 0.38 (0.17–0.86) § |
Adverse outcomesb | 2.49 (1.63–3.81) ‡ | 0.79 (0.49–1.27) | 0.99 (0.66–1.49) | 0.89 (0.51–1.56) | 1.20 (0.56–2.55) | 0.53 (0.20–1.44) |
Previous infertilityb | 1.38 (0.88–2.14) | 0.84 (0.51–1.40) | 1.28 (0.85–1.95) | 1.02 (0.56–1.87) | 0.95 (0.42–2.13) | 1.39 (0.61–3.17) |
Pregnancy intentions | ||||||
Definitely not | (reference) | (reference) | (reference) | (reference) | (reference) | (reference) |
Not sure/Don’t know | 1.13 (0.70–1.84) | 1.15 (0.66–1.98) | 1.27 (0.80–1.99) | 2.27 (1.12–4.63) § | 2.50 (1.11–5.66) § | 0.84 (0.34–2.10) |
In the next 3+ years | 0.85 (0.45–1.59) | 1.11 (0.59–2.10) | 1.28 (0.74–2.20) | 1.43 (0.66–3.10) | 1.06 (0.33–3.36) | 0.59 (0.19–1.80) |
Within 2 years | 2.11 (1.30–3.43) ‡ | 1.39 (0.79–2.42) | 1.62 (1.03–2.55) § | 0.97 (0.52–1.79) | 0.83 (0.31–2.22) | 0.86 (0.34–2.13) |
Attitudes
Perceived awareness of preconception risk factors | Perceived importance of preconception health | Interest in knowing more about preconception health | Preconceptional self-efficacy | Preconception lifestyle change intentions | |
---|---|---|---|---|---|
Age | |||||
18–24 years | (reference) | (reference) | (reference) | (reference) | (reference) |
25–29 years | 0.95 (0.64–1.40) | 0.89 (0.59–1.33) | 0.93 (0.64–1.36) | 0.98 (0.66–1.47) | 0.81 (0.55–1.18) |
30–34 years | 2.16 (1.34–3.47) † | 1.40 (0.86–2.26) | 0.74 (0.46–1.18) | 1.62 (0.99–2.65) | 1.09 (0.69–1.71) |
35–39 years | 2.66 (1.58–4.49) † | 0.90 (0.56–1.46) | 0.70 (0.42–1.16) | 1.37 (0.81–2.32) | 0.87 (0.56–1.37) |
40–48 years | 2.68 (1.55–4.62) † | 1.36 (0.85–2.18) | 0.37 (0.21–0.63) † | 2.20 (1.30–3.73)† | 1.08 (0.70–1.69) |
Household income | |||||
< £19,000 | (reference) | (reference) | (reference) | (reference) | (reference) |
£19,000–£25,999 | 0.55 (0.32–0.94) ‡ | 1.50 (0.85–2.64) | 0.95 (0.55–1.66) | 0.80 (0.45–1.43) | 0.70 (0.40–1.20) |
£26,000–£31,999 | 1.20 (0.69–2.08) | 1.92 (1.06–3.49) ‡ | 1.28 (0.73–2.23) | 0.87 (0.48–1.60) | 0.86 (0.49–1.53) |
£32,000–£47,999 | 1.36 (0.85–2.18) | 2.21 (1.32–3.69) † | 1.47 (0.91–2.37) | 0.96 (0.58–1.59) | 0.76 (0.47–1.22) |
£48,000–£63,999 | 1.15 (0.72–1.81) | 2.81 (1.70–4.62) † | 1.29 (0.80–2.09) | 1.02 (0.61–1.71) | 0.90 (0.56–1.44) |
£64,000–£95,999 | 1.66 (1.04–2.67) ‡ | 2.46 (1.49–4.08) † | 1.86 (1.14–3.03) ‡ | 1.39 (0.83–2.35) | 1.04 (0.65–1.65) |
≥ £96,000 | 1.54 (0.91–2.61) | 3.38 (1.90–6.00) † | 1.46 (0.84–2.54) | 1.33 (0.73–2.41) | 0.92 (0.54–1.57) |
Education | |||||
School | (reference) | (reference) | (reference) | (reference) | (reference) |
Intermediate | 1.16 (0.67–2.02) | 1.23 (0.69–2.20) | 1.08 (0.62–1.90) | 1.11 (0.62–2.00) | 0.83 (0.49–1.42) |
University | 1.19 (0.71–2.00) | 1.20 (0.70–2.07) | 1.25 (0.74–2.11) | 1.32 (0.76–2.30) | 0.99 (0.61–1.61) |
Minority ethnicitya | 0.80 (0.48–1.32) | 1.98 (1.18–3.31)‡ | 2.28 (1.41–3.69) † | 1.24 (0.72–2.14) | 1.61 (0.92–2.81) |
Born outside the UKa | 1.36 (0.84–2.18) | 1.26 (0.75–2.10) | 1.37 (0.82–2.28) | 1.78 (1.06–3.00)‡ | 1.80 (1.06–3.05)‡ |
Ever pregnanta | 3.08 (2.24–4.23) † | 0.92 (0.67–1.28) | 1.79 (1.30–2.46) † | 1.06 (0.76–1.46) | 1.04 (0.80–1.35) |
Previous live birth(s)a | 4.10 (2.89–5.82) † | 0.81 (0.57–1.15) | 1.84 (1.29–2.62) † | 0.95 (0.66–1.36) | 0.99 (0.76–1.29) |
Adverse outcomesa | 1.91 (1.32–2.77) † | 1.14 (0.78–1.65) | 1.50 (1.04–2.16) ‡ | 1.38 (0.94–2.03) | 1.34 (0.94–1.90) |
Previous infertilitya | 1.39 (0.94–2.05) | 0.76 (0.50–1.13) | 1.02 (0.70–1.49) | 0.95 (0.64–1.43) | 1.40 (0.95–2.07) |
Pregnancy intentions | |||||
Definitely not | (reference) | (reference) | (reference) | (reference) | (reference) |
Not sure/Don’t know | 0.79 (0.53–1.20) | 1.14 (0.75–1.73) | 2.98 (1.97–4.49) † | 0.88 (0.57–1.36) | 0.86 (0.60–1.23) |
In the next 3+ years | 0.77 (0.48–1.25) | 1.12 (0.69–1.83) | 6.06 (3.71–9.90) † | 0.89 (0.53–1.49) | 0.82 (0.57–1.19) |
Within 2 years | 1.28 (0.85–1.93) | 1.36 (0.89–2.06) | 12.64 (8.13–19.64) † | 1.05 (0.68–1.62) | 1.04 (0.72–1.50) |