Table 1.

Comparison of lifestyle interventions applied in the LIFEstyle and RADIEL study

	LIFEstyle study	RADIEL study
Inclusion criteria	Age 18–39 years BMI ≥29 kg/m2 Chronic anovulation or infertility >1 year	Age >18 years BMI ≥30 kg/m2 and/or prior GDM
Goal	5–10% weight reduction BMI <29 kg/m2	5% pre-pregnancy weight reduction No gestational weight gain during first and second trimester of pregnancy
Amount of consultations	Max. 10 consultations in the 6 months before fertility treatment: 6 outpatient clinic visits 4 telephone consultations	Max. 14 consultations: Every 3 months before pregnancy (max. 5 visits) 3 times in pregnancy (1/trimester) 3 times after pregnancy (6 weeks, 6 months and 12 months postpartum) 3 group sessions (baseline, 6 and 12 months postpartum)
Diet	Reduction of caloric intake of 600 kcal/day, with a minimum intake of 1200 kcal/day using an online diary. Improve diet quality.	Reduction of caloric intake to 1600–1800 kcal/day. Using the plate model (40–50% carbohydrates, 30–40% fats and 20–25% proteins). Improve diet quality.
Physical activity	Daily physical activity aimed at 10 000 steps per day using a pedometer. Moderate-intensity physical activity for at least 30 min, 2–3 times a week.	Daily physical activity aimed at 10 000 steps per day, using a pedometer. Moderate intensity physical activity for 150 min/week.
Motivational counselling	Individualized motivational counselling: ^ Awareness of actual lifestyle leading to overweight or obesity. ^ Awareness of healthy lifestyle in relation to infertility. ^ Formulating individualized goals embedded in a ‘patient contract’. Motivation to change physical activity was monitored by the ‘Physician-based Assessment and Counselling for Exercise’ and counselling was adjusted accordingly.	Individualized motivational counselling based on personal preferences. Contact with local physical activity counsellor and entry tickets for local sport clubs. Goals were adapted to pregnancy on individual basis.